Download BMW E46 Complete Vehicle Manual

Table of Contents
E46 MODELS
Subject
Page
E46 Sedan and Coupe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
E46/4 Sedan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
E46/2 Coupe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Body
Body Shell. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Hood and Headlights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Doors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Door Anchoring System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Door Handles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Sunroof. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Interior Features. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Driver Information Displays. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Seats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Power Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Front Suspension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Rear Suspension. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Final Drive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Brake System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
E46 Sport Wagon. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Body Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Body . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Interior. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Initial Print Date: 11/00
Revision Date:11/16/00
Subject
Page
Rear Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Center Arm Rest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Child Seat Restraint . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Cargo Area . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Emergency Release . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Rear Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
E46 Convertible. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Body Shell
Floor Pan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Windshiel Frame. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Rear Bulkheads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Tension Strut. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Aluminum Support Plate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
Rear Seats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Variable Top Storage Compartment. . . . . . . . . . . . . . . . . . . . . . . .43
E46 All-Wheel Drive. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chassis
Front Axle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Steering. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Differential and Front Axles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .50
Rear Axle. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Tires and Wheels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Transmissions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Transfer Case. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
E46 Sedan and Coupe
Model: E46/4: Sedan, E46/2: Coupe
Production Dates: E46/4 from 6/98, E46/2 from 6/99
Objectives:
After Completing this module you should be able to:
•
Identify the location and purpose of the Door Anchoring Hooks.
•
Describe the Suspension Systems used on the E46.
•
Describe how to make a Camber adjustment to the front wheels.
•
Identify vehicle fuse locations.
3
E46 Models
E46/4 Sedan
The E46 is the successor to the E36 and is the next evolution in the 3 series development.
The E46/4 Sedan was introduced as a 1999 model as both the 323i and 328i.
The E46 3 series vehicle offers more comfort, safety, space and equipment than the previous E36, without compromising the sporty characteristics of the 3 series vehicle.
Since start of production,two engine variants have been offered, the M52TU and the M54
six cylinders. Both engines introduced changes and design improvements that will be covered in the Engine and Engine Management chapters.
4
E46 Models
E46/4 Dimensions
5
E46 Models
E46/2 Coupe
The E46/2 Coupe was introduced as a 2000 model year vehicle in both 323Ci and 328Ci
variants.
The body of the E46 /2 Coupe is not a modified sedan, but is a completely distinct body.
There are no sheet metal parts shared between the Sedan and the Coupe Only the design
technology of the E46/4 was used to create the E46 Coupe. The Coupe is even longer and
wider than the sedan.
The E46 Coupes have been given the “Ci” (coupe injected) trunk badge designation. This
is a departure from the “is” (injected sport) from previous 3 series coupes.
Since start of production,two engine variants have been offered, the M52TU and the M54
six cylinders. Both engines introduced changes and design improvements that will be covered in the Engine and Engine Management chapters.
6
E46 Models
E46/2 Dimensions
7
E46 Models
Body
Body Shell
The structural rigidity of the E46 body shell was increased using computer aided design
(CAD) techniques. Every component of the new body structure was designed using this
method. CAD allows the design to be translated into computer aided manufacturing (CAM)
more efficiently. To reduce the weight of the vehicle, while retaining strength, high strength
steels are used and now amount to 50% of the body shell weight.
The second area of focus of the body shell is "structural dynamics". This deals with vibration frequencies that effect the ride quality and rigid feel. The E46 body shell was designed
so that the frequencies for torsional twisting and bending are separated and are in an
inaudible range. The ranges match the E39 for twisting at 29 hertz and bending at 26 hertz.
The E46 continues with BMW’s safety cage concept for passenger protection. The tubular
impact structures continue to provide protection against body damage during front or rear
impacts.
The E46 is 1.8 times more able to absorb energy in a 40mph offset frontal crash than the
E36.
8
E46 Models
Hood and Headlights
The E46 follows the E38/E39 design with the kidney grille being integrated into the hood.
The grille openings are more rounded and sweep down to the front bumper. The cowl
opening is now integrated in the hood and is similar to the E38. The hood can be opened
to a maximum of 90°, the workshop position, by disconnecting the gas struts and inserting a pin in the aligned holes.
The hood is opened by first pulling the release lever located inside the vehicle and then
releasing the secondary catch that pops out of the grille.
The E46 carries on with the traditional four head lamp configuration, however, no internal
lens is used over each lamp. The free-form reflectors are clearly visible through the smooth,
plastic covers. The plastic covers are lighter in weight and more resistant to breakage than
the previous glass covers.
Vertical and horizontal adjustments for the head lamps are located on the upper rear edge
of the assemblies.
Xenon low beam head lamps will be an available option starting with 9/98 production.
Xenon headlights are discussed in the E46 Driver Information Chapter.
9
E46 Models
Doors
The doors on the E46 feature the door anchoring system introduced with the E38. The
anchor consists of a horizontal bar in the door and a hook at the rear edge. The hook rests
in a recess in the "B" and "C" pillars and it reinforces the body in the event of a side impact.
The door seal design is copied from the E39 and is a single piece seal.
10
E46 Models
Door Anchoring System
Cross section of driver’s door and
“B” pillar in the normal closed position.
Upon severe impact, the hook
locks into the recessed notch to
provide a unitized side impact protection system.
After impact, the door springs
back and unhooks the notch.
The door is clear of the “B” pillar
and can be opened.
11
E46 Models
Door Handles
The door handles and locking system on the E46 are of a new design. The new bow type
handles allow the doors to be opened easier. The locks are fully encapsulated including the
electrical components. The new door handle/latch/lock assembly offers improved reliability
and security against theft. The micro-switches for door position and lock condition have
been replaced by hall sensors.
There are no serviceable components on the lock assembly and it must be replaced as a
unit.
From September 2000 production, there was a modification done to the door handles of
the E46. The modified door handles when pulled, fold upward instead of straight out as
previous. The lock assembly was also modified to accommodate the new articulation of
the door handles.
12
E46 Models
Sunroof
The sunroof design is similar to the E38/E39, however, the sunroof cassette is not serviceable and must be replaced as a complete unit. The sunroof is an option on the E46 and will
come with a glass panel (moon roof) instead of a steel panel.
13
E46 Models
Interior Features
The interior of the E46 has been completely redesigned with an emphasis on more space,
luxury and convenience without compromising the 3 series sporty characteristics.
The new instrument panel/dash is similar in design to the E39 with a slightly less pronounced orientation to the driver. The E38/E39 type face vent grills are used for air distribution.
The multi-function steering wheel is available on both the 323/325 models and standard
on 328/330 models. There are two different steering wheels available, the four spoke wheel
with MFL and a three spoke sport wheel with MFL. The three spoke sport wheel is optional for sedans and standard in coupes. The MFL includes the controls for the audio system
on the left and the cruise control on the right.
The E46 comes equipped with a manually adjustable (tilt/telescopic) steering column. There
is 30 mm of vertical and horizontal adjustment for the steering column.
1. Spring
2. Clamping mechanism
3. Steering lock with
steering column tube
14
E46 Models
Driver information Displays
The primary display for driver information is located in the instrument cluster. The coupe and
sedan have different cluster lettering and faces. The secondary display in the console consists of the audio system and automatic climate control panel (if equipped with IHKA).
80
100
40
12
0
11
20
3
100
60
2
120 140
160
180
80
60
200
40
220
240
20
4
5
1/min
x1000
120
6
1
140
UNLEADED GASOLINE ONLY
km/h
0
50 30 20 15
7
12
MPH
Two different radio types are available. One
with the integrated tape player and the other
radio incorporating a single in dash CD player.
Accessory switches are located in the console
below the heater control panel. These include
the ASC switch and the heated seat switches.
Later production vehicles (2000 M.Y.) utilize the
SZM (Center Console Switching Center) in
place of the separate switches.
A new design (push to open/pull up to close)
window switches are located in the center console on either side of the gear shift lever. The
power window circuits include the one-touch
and anti-trap features.
Instrument Cluster electronics and audio systems
are covered in the E46 Driver Information Chapter.
15
E46 Models
Seats
The front seats are similar in design to the E36 seats with new internal construction to
improve their support and comfort. Memory for the drivers seat position is available. The
seat controls, including memory storage buttons are located on the side of the seat base.
An optional lumbar support is also available for the E46.
16
E46 Models
A split folding (40/60) seat is available as an option on sedans and standard on coupe
models.
The release for the folding seat backs is located in the trunk on the left and right sides near
the wheel arches. This increases the security aspect when keeping items locked in the
trunk.
17
E46 Models
Power Distribution
The battery is installed in the trunk of the E46 and features lead/calcium plate material for
true maintenance free operation. The water usage of this battery is low throughout its service life.
The Battery Safety Terminal is installed at the positive terminal of the battery. A repair kit is
available for the BST.
The E46 is produced with a vehicle specific wiring harness. This harness is based on the
ordered optional equipment of the vehicle so that it contains the proper connectors and
connections. Options can not be added at a later time without replacing the entire harness.
Specific kits are available to repair the harness in the event of an accident or damage to the
harness. These repair kits include:
• Engine compartment
• Vehicle’s rear area
If the entire harness need to be replaced, a new harness with the maximum equipment or
options must be ordered. This is the only harness that will be stocked in the parts system.
18
E46 Models
There are three locations for fuses on the E46:
• The fuse holder above the glove box
• The E-Box in the engine compartment
• In the trunk near the battery
The E46 uses high amperage fuses for circuit protection. The battery power supply is protected by a 250 amp fuse in the trunk.
19
E46 Models
Front Suspension
The single ball joint, strut axle of the E46 is based on the E36 design. Design and component changes were developed to improve the ride quality and handling characteristics. The
following changes are incorporated into the E46 front suspension system:
• A new forged aluminum control arm is used on the E46 (except all-wheel drive). It offers
the advantages of weight reduction and lower unsprung mass.
• Hydraulic bushings are used for the rear lower control arm support.
• Hollow strut piston rods are used to reduce weight
• The steering knuckles are press fit into the strut tubes which reduces the tolerances of
the front suspension geometry.
• The caster has been increased to improve straight line stability.
• The track has been widened for improved cornering.
• Aluminum brake dust shields are used for weight reduction
Altogether there is 5.72 lbs less unsprung weight in the front suspension which enhances
ride comfort and handling.
20
E46 Models
Front Camber Adjustment
The top of the strut is mounted through elongated holes. The strut is fixed in position when
the vehicle is assembled. If minor corrections need to be made to the front end alignment,
the pin can be driven down and the strut can be moved in the slots to adjust the camber.
Approximately .5o of adjustment is available by moving the strut in the slots.
Follow the instructions for
making the Camber adjustment described in Repair
Manual 32 00 610.
Use Special Tool 32 3 140
to make the adjustment.
21
E46 Models
Rear Suspension
The design of the E46 rear suspension is based on the E36 "C" arm type. However, all
components of the suspension are new and designed to suit the E46 for:
• Comfort and convenience
• Handling and stability
• Noise reduction
The sub frame is a new design employing steel tubes and metal sections. It is more rigid
than the previous sub frame. This provides a stable platform for the rear suspension to
work from. The differential is mounted to the sub frame using a hydraulic mount. The sub
frame is mounted to the body at four vibration absorbing rubber mounts.
The upper transverse control arms are made from cast aluminum for weight saving.
22
E46 Models
Final Drive
The final drive is the compact (HAG
188K) type that is lighter in weight
than the type used on the E36.
Features of the compact final drive
assembly include:
•
•
•
•
•
•
Compact housing
Shorter pinion shaft
Hollow drive flange shafts
No side bearing covers
Elimination of speedometer gear
Lifetime synthetic oil
Limited slip differential is no longer possible with the compact differential.
The drive shaft and differential are now mounted on the center line of the vehicle. This
enables the transmission tunnel to be narrower increasing the interior passenger space.
With this change, the axle shafts are now different in length and are no longer interchangeable.
Brake System
The braking system is upgraded for the E46 to match the vehicle’s size and braking requirements. The dual circuit (front/back) distribution system continues to be used for optimized
braking response and performance. Refinements to the brake pedal linkage increase the
brake response time to improve braking performance.
Single piston floating calipers with vented rotors are
used on the front and rear brakes.
The E46 uses a 10" vacuum booster, vented in the engine compartment to reduce noise in
the passenger compartment.
23
E46 Models
E46 SPORT WAGON
Model: E46/3
Production: 1/00
Objectives:
After completing this module you should be able to:
•
Identify the changes to the body of the E46 for the Sport Wagon.
•
List the changes to the interior of the E46 Sport Wagon.
•
Discuss the operation of the rear tailgate/window system.
The E46/3 “Sport Wagon” is being introduced to the US market as a 2001 Model Year vehicle. It joins the highly successful Sedan and Coupe models to further enhance the product
line up and offer 3 series customers an alternative choice of vehicle.
Up to the “B” pillars, the Sport wagon is identical to the E46 sedan. The rear doors have
been remodeled for wagon usage and the tail gate is similar to the E39 Sport Wagon with
an opening rear window.
The rear seats fold down to provide 1345 liters of cargo space. With the seats up, the rear
compartment provides 435 liters of load space.
00E46SPTWGN0400
24
E46 Models
BODY SPECIFICATIONS
758 mm
1471 mm
1478 mm
1739 mm
1932 mm
995mm
2725 mm
1382mm
1378mm
4478 mm
41E46SPTWGNSPEC0000
The E46 Sport Wagon is 7 mm longer that the sedan and the unloaded height is 6 mm
lower. The wheel base, width and turning radius are the same as the E46 sedan. The following are the maximum cargo capacity/ loads:
• 435 Liters luggage capacity - with rear seat back up
•1345 Liters luggage capacity - with back rest down
• 540KG in the rear
• 75 KG on the roof.
25
E46 Models
Body
From the front bumper up to the “B” pillar the E46 Sport Wagon body is identical to the
sedan. From the “B” pillar rearward, the body shell of the Sport Wagon is all new and
includes:
•
•
•
•
•
•
New Rear doors
New Tailgate and hinge mechanism
New Frameless rear window
New Rear Bumper
No tail gate lock cylinder
Roof rails as optional equipment
The structural rigidity and “structural dynamic” characteristics introduced with the E46
sedan are carried over to the E46 Sport wagon. As with the sedan and coupe, the Sport
Wagon body shell acts as the passenger’s safety cage along with the tubular impact structures for the front and rear bumper mountings.
41E46SPTWGNREAR00
41E46SPTWGNREAR0100
26
E46 Models
Interior
Up to the “B” pillar, the interior equipment and trim level corresponds to the E46 sedan. The
front seat options are the same as the E46 Sedan, while the rear seating area has been
newly designed to provide an attractive package that offers optimum functionality and useable space when the seats are folded down for cargo loading.
52E46BACKSEAT0200
The rear seats backs are a 60/40 split with the center arm rest section on the left seat back.
The center passenger’s inertia reel is mounted to the left seat back, while the left/right rear
passenger’s belt reels are mounted on the wheel housings. The lower section of the seat
back is separate foam piece that enables the back rest pivot point to be higher on the seat
back. This allows the back rest to fold flat for more useable cargo loading space.
27
E46 Models
Center Arm Rest
The center arm rest incorporates the non-adjustable center head rest. The center arm rest
is folded down to gain access to the storage compartment and cup holders , which are
integrated into the rear of the head rest.
CUPHOLDER
STORAGE COMPARTMENT
52E46SPTWGNCUP0500
28
E46 Models
Child Seat Anchor
There are three child seat hold down anchors positioned behind the rear seat back rest.
The plastic covers must be removed to access the hold down anchors,
CHILD SEAT ANCHOR
29
E46 Models
Cargo area
The cargo area offers 435 liters of cargo space with the rear seat back rest raised and 1345
liters with it lowered. The cargo area offers a spring loaded - roller blind and cargo net similar to the E39 Sport Wagon.
51E46SPTWGNCARGONET0000
00E46SPTWGNCARGO0500
30
E46 Models
ANTENNA AMPLIFIER
Storage Compartments
Storage areas on the left and right in the
rear are used to house the rear window
washer fluid reservoir on the right and various sound system components on the left.
OOL KIT
66460001
SOUND SYSTEM
COMPONENTS
SPARE TIRE
WINDOW WASHER
FLUID RESERVOIR
Load Floor/Spare
The load floor is removable to access the
spare tire and control module mounting
area located beneath. A strap is provided to
hold the load floor up while accessing the
storage area. The interior trim panel must
also be removed for access to the spare
and control modules.
Power Socket
A 12 Volt power socket is installed on the
left side of the cargo area behind the rear
seat back.
65460001
61460001
31
E46 Models
Tail gate
The tail gate is similar in design to the E39 Sport Wagon, including the rear glass that is
hinged separately and can be opened independently from the tail gate.
TAILGATE RELEASE
SWITCH
Rear Actuator
The actuator for the tailgate release is mounted
on the rear apron behind the trim panel. Control
of the actuator is a function of the GM - ZKE
system.
32
E46 Models
Emergency Release
The tailgate does not feature a lock cylinder so an emergency release mechanism is incorporated into the tail gate latch. It allows mechanical opening of the gate actuator in the
event of an electrical failure. The release is located along the lower edge of the rear apron
behind a small access cover. After removing the cover, the lever is pushed to the right to
mechanically release the tail gate.
EMERGENCY RELEASE
The rear apron of the E46 Sport Wagon is lowered for easier loading/unloading. A plastic
rubbing strip prevents the bumper from being scratched when cargo is being
loaded/unloaded.
33
E46 Models
Rear Window
The Frameless rear window is bonded to a metal carrier which is hinged to the body. If the
rear window needs replacement, it is supplied with the glass bonded to the metal carrier.
The release switch for opening the rear glass is incorporates into the rear wiper arm cover
under the triangle trim plate.
REAR WINDOW SWITCH
34
E46 Models
Rear Glass Hinge
The hinges are a new design (torsional
coil spring) that are compact in shape for
space saving reasons.
41460001
The rear window is adjusted through the
slotted mounted bolts. The gap of the
window should be uniform on all sides.
The height of the rear window is adjusted using shims on the hinge mounts.
Refer to the repair manual for complete
adjustment procedures and sequence.
Rear Washer Nozzle
The rear window washer spray nozzle, as well as the third brake light, is mounted at the top
left side integrated into the spoiler.
63E46SPTWGNTAILLIGHT0000
35
E46 Models
E46 Convertible
Model: E46/2C
Production: 01/00
Objectives:
After completing this module, you should be able to:
•
Describe how the body shell is reinforced to improve Torsional Rigidity
•
Identify the floor pan reinforcements for energy absorption on the SGS seats.
•
Identify the body shell reinforcements necessary for the addition of the Variable
Convertible Top Storage Compartment Floor.
•
Describe how the windshield frame is reinforced.
•
Identify and describe the functions of the Tension Strut.
•
Identify and describe the function of the Aluminum plate.
36
E46 Models
Introduction
The E46 Convertible is the replacement for the E36 Convertible and is based on the E46
Coupe. It is initially being introduced in March 2000, as a 323 Model only with the M52 TU
2.5 liter engine. The 3 liter version of the E46iC will begin production starting in 6/2000.
The E46 323 features a new design top that consists of a three layer top and all glass rear
window. The 323 comes with a manual top as standard equipment. The new fully automatic
electro-hydraulic top is available as an option. The 330 E46iC will come with the fully automatic top as standard equipment.
The roll over protection system is standard equipment and is similar in design to the E36
system. The roll over protection bars are hidden by the rear headrest and deployed under
the same criteria as the E36 system.
The front seats of the E46iC are a new design with the seat integrated belt (SGS) system
similar to the system introduced on the E31 - 8 series vehicles.
00E46ICINTRO100
37
E46 Models
TECHNICAL DATA
38
E46 Models
TECHNICAL DATA
E36
Length (mm)
Width
(mm) (with mirror)
Length (mm)
Width
(mm) (With
Mirrors)
Height
(mm)
Outside Car Dimensions
Height (mm)
Shoulder
front (mm)
Inside Room,
Car Dimensions
Shoulder
Room,
rear(mm)
(mm)
Shoulder
Room, front
Shoulder
Room,front
rear (mm)
Elbow
Room,
(mm)
Elbow Room, front (mm)
Elbow
rear
(mm)
ElbowRoom,
Room, rear
(mm)
Effective headroom, front (mm)
Effective
headroom, front (mm)
Effective headroom, rear (mm)
Effective headroom, rear (mm)
E46
E36
Convertible
Convertible
E46
Convertible
Convertible
(323i)
4433
1710
(1875)
4433
1710
1348(1875)
(323i)
4488
1757 (1947)
4488
1757 (1947) 1372
1648
1352
1108
1352
1108
1412
1412
1120
1120
968
968
921
921
1672
1384
1165
1443
1208
974
937
1384
1165
1443
1208
974
937
General Information
Cd
Cd
Unladen weight
Unladen weight (lb)
Total Weight
Total Weight
(lb) (L)
Luggage
Comp. Volume
(Comp Floor Extended
SpeedComp.
Rating Volume (L)
Luggage
Top Speed
(MPH)
(Comp
Floor
Extended)
Acceleration 0-60 MPH (Sec.)
Top Speed (MPH)
Acceleration 0-60 MPH (sec)
0.36
0.36
3319
3319auto)
(3396
4035auto)
(3396
(4112 auto)
4035
230
(4112 auto)
230
0.36
0.36
3516
(3649 auto) 3516
4322 (3649 auto)
(4410 auto)
4322
260
(300) (4410 auto)
260
(300)
128
governed
128
governed
7.7
128
8.8 auto
8.8
128
9.7 auto
preliminarygoverned
governed
7.7
(8.8 auto)
8.8
(9.7 auto)
preliminary
39
E46 Models
Body Shell
The body shell of the E46iC has been developed specifically for the convertible to improve
crash performance which is similar to the E46 Coupe. This was achieved by the use of
reinforcements on the body shell that improved torsional rigidity (body twisting). In the main
body floor pan, reinforcements were necessary to accommodate the new SGS (Seat
Integrated Belt System) seat system. In the rear floor pan, reinforcements were necessary
to account for the variable convertible top storage. compartment floor.
ART-E46BODY3
Components
Floor Pan
The floor pan is reinforced to support the SGS seat by heavier cross brace members, reinforced tunnel/floor pan and reinforced engine support brackets. During a collision all forces
occurring on the seat are channeled to be absorbed by the floor pan.
Windshield Frame
The windshield frame is reinforced with stepped
reinforcing tubes to allow it to act as a roll-over protection. During the rollover all of the forces exerted
on the A-pillar of the windshield frame are transmitted as a Moment (Torque) to the bottom of the Apillar where stepped reinforced tubes are reinforced.
ART-E46BODY4
40
E46 Models
Rear Bulkheads
The rear bulkheads are redesigned to support the rollover protection and seat belts. They are welded to
increase structural rigidity and to secure rear seat, rear
seat belts and the mounting point for the ISO child seat.
ART-E46BODY5
Variable Top Storage Compartment
The variable top storage compartment is reinforced to make the top storage compartment
rigid and stronger, not to allow twisting moments when the soft top is in its compartment
or when the compartment is opened to enlarge the storage area.
Tension Strut
Tension struts are integrated into the rear of the
body shell to improve the torsional rigidity by not
allowing body twist in the rear. It also keeps the
rear end of the car intact with the middle floor
pan.
41E46STRUT0100
Aluminum Support Plate
An aluminum support plate is incorporated into
the front suspension carrier to achieve a high
degree of rigidity combined with low weight.
All of these design improvements increased the
E46iC torsional rigidity by 50% compared to the
E36iC:
41E46PLATE0200
• E36 Convertible Torsional Rigidity 6000Nm/degree
• E46 Convertible Torsional Rigidity 9000 Nm/degree
41
E46 Models
REAR SEATS
The E46iC is designed as a four passenger vehicle. Only two seat belts are installed in the
rear that correspond to the seat belt system of the E36iC.
The E46iC is equipped with child seat mounting brackets on the left and right sides below
the seat base. The brackets conform to ISO (International Organization of Standardization)
for placement on the rear floor pan. Any ISO child seat can be installed by simply sliding
the seat into position between the seat base and backrest and locking it into place.
42
E46 Models
VARIABLE CONVERTIBLE TOP STORAGE COMPARTMENT FLOOR
Purpose of the System:
The trunk of the E46 convertible offers a new feature called the “Variable Convertible Top
Storage Compartment Floor”. This feature allows the luggage storage area to be enlarged
by approximately 40 liters when the soft top is raised or removed for hard top installation.
Components of the system:
Variable Compartment Floor
The variable compartment floor is constructed of plastic with fabric covering. It is hinged
mechanically so that it can be rotated up into the top storage area providing additional luggage storage space in the trunk. The floor is hinged at four points to allow it to articulate
and fold upwards:
43
E46 Models
Actuating Lever
An actuating lever is integrated in the variable compartment floor on the right side. It allows the compartment floor to be opened and closed using the
actuating lever. It also locks the compartment floor
into position.
Dampening Piston
A dampening piston is also integrated in the
variable compartment floor on the right side.
It assists in the movement of the variable
compartment floor to either position and keep
it fixed in that set position (retracted or
extended). The lower dampening piston
hinge switches the micro switch integrated
on the right side of the compartment floor
when the variable compartment floor is in the
raised position. This signal is provided to the
CVM to lock out the operation of the convertible-top.
DAMPENING
PISTON
MICRO-SWITCH
System Operation:
Opening the variable compartment floor
• The convertible top must be raised or removed from the storage compartment.
• Pull the actuating lever rear wards and push it down and toward the rear bulkhead.
Closing the variable compartment floor
• Pull the actuating lever down.
• Pull the compartment floor rear wards to close the floor.
44
E46 Models
E46 ALL-WHEEL DRIVE SYSTEM
Model: E46/16 (330xi/A, 325xi/A, 325xi/A Sport Wagon).
Production date: 330xi 8/00, 325xi 9/00.
Objectives
After completing this module you should be able to:
•
Identify the changes made to the E46 to accommodate all-wheel drive.
•
Understand the construction of the NV124 transfer case.
45
E46 Models
Introduction
The E46/16 introduces the return of the BMW all-wheel drive car to the United States. This
time all-wheel drive will be an option (SA 203), available on E46 sedans and Sport Wagons
beginning 2001M.Y.
Vehicles with the all-wheel drive option have been given the engineering designation of
E46/16.
One of the significant changes from the previous E30 ix is that the E46/16 does not use a
viscous coupling or limited slip differential. The all-wheel drive system has largely been
taken from the X5 concept. It uses two open differentials and a single speed transfer case.
Power distribution is 38% to the front and 62% to the rear, giving the E46/16 the feel of a
genuine rear-drive road car.
With it’s additional 17mm ground clearance, the xi is particularly suited to stretches of snow
and ice covered roads and its sure footedness is made possible by the use of the Bosch
DSC III 5.7 system, first used on the X5.
Performance of the all-wheel drive E46 does not suffer either, this is because of a lightweight all-wheel drive system that only adds 100kg (220lbs). Weight distribution is largely
unaffected at 52.7% front and 47.3% rear (2wd: 51.0% front, 49.0% rear).
325xi
46
E46 Models
Changes from the standard drive version are:
•
A specially designed body pan with a widened transmission tunnel and modifications on
the driver’s side to accept the transfer case.
•
Modified oil pan and engine mounts to provide access for the front axles.
•
A completely new front engine carrier.
•
Re-reinforcements for the front strut bearings.
•
A compact new transfer case (NV 124).
•
New transmission cross-member.
•
Bosch DSC III 5.7
47
E46 Models
Chassis
Front Axle
The front axle has been completely re-designed over the standard drive E46. All
components are constructed of steel.
The front axle carrier consists of two
square frame sections welded to two
tubes to form a box structure. The
axle carrier is bolted to the vehicle
frame at both the front and rear
attachment points.
Front
The pivot at the apex of the lower
control arms are a separate ball joint
bolted to the axle carrier.
The purpose of the re-design of the
lower control arms and mounting
points is to provide clearance for the
front axle shafts.
The steel lower control arms, which
are smaller than the aluminum arms
used on the 2wd model attach at the
rear to the axle carrier.
Ball Joint
Lower Control Arm
The hydraulic engine mounts are
different from the 2wd version and
have also been relocated to provide
front axle clearance.
The front sway bar has been increased in diameter to 23.5mm (2wd standard: 23mm,
sports suspension: 24mm) to accommodate the additional weight. A sports suspension
option is not available for the xi.
48
E46 Models
The struts are shorter than the 2wd and there are reinforcement plates between the strut
bearing and the sheet metal of the strut towers to prevent deformation when traveling on
very poor road surfaces.
The spring travel of the E46/16 is
approximately 20mm less than
the 2wd version.
The shorter front axle spring
travel is due to the limited angle
of deflection of the front axle
shafts.
Steering
The rack and pinion steering unit
has been modified from the 2wd.
It is constructed with a
larger diameter piston.
This is necessary to counter the
additional drag of the all-wheel
drive system and the wider
standard wheels and tires.
The lower steering spindle is
different than the 2wd and
connects to the steering rack via
a double cardan joint.
Turning radius of the E46/16 is
35.8ft, 1.4ft greater than the
2wd.
49
E46 Models
Differential and Front Axles
The differential for the front axle is bolted to left side of the engine oil pan. The differential
is driven by a 40mm single piece drive
shaft. The drive shaft has universal Right Side Support Housing
joints at both ends.
Type:
Axle ratios:
Auto:
Man:
Max torque:
Weight:
VAG 174
330xi
325xi
3,46:1
3,46:1
3,07:1
3,23:1
2000Nm
40 lbs
Lifetime fluid fill: SAF-XO
The oil sump has been modified to accommodate the right side axle. A connecting tube is
welded into the oil pan. A shaft runs inside of the connecting tube between the front
differential and the axle shaft on the right side.
Two drive shafts of equal length are used to
transmit power to the front wheels.
The steering knuckle is modified to
accept the CV joint of the front axles.
The front wheel bearings are unique
to the E46/16 and incorporate the
wheel speed sensor pulse wheel into
the bearing seal.
50
E46 Models
Rear Axle
The complete rear axle and the rear differential are the same as the 2wd version of the 325i
and 330i.
Type:
Axle ratios:
Auto:
Man:
Max torque:
Weight:
HAG 188N
330xi
325xi
3,46:1
3,46:1
3,07:1
3,23:1
3000Nm
84 lbs
Lifetime fluid fill: SAF-XO
The rear spring/strut travel of the E46/16 is approximately 17mm less than the 2wd version.
The reason for the reduced travel in the rear is to oppose any excessive body roll as a result
of the higher body profile.
The rear sway bar has been increased in diameter to 20mm (2wd standard: 18mm, sports
suspension: 19mm) to accommodate the additional weight.
Tires and wheels
Standard wheel size is 17x 7.0 to ensure there is enough room for the front axles and
brakes. Tire size is 205/50 R17 All-season radials
330xi Double Spoke 17x7.0
325xi Radial Spoke 17x7.0
51
E46 Models
Transmissions
There are two transmission variants for the 325xi and 330xi.
The manual transmission for both versions is
the S5D-280Z direct gear transmission. The
extension housing is modified to accept the
transfer case.
The transmission has a lifetime fill of MTF-LT1
synthetic transmission fluid.
S5D-280Z
The automatic transmission for both the 330xi
and 325xi is the A5S-390 R (General Motors)
transmission with GS 20 AGS control and
Steptronic shifter.
The transmission has a lifetime fill of Texaco
8072B.
A5S-390R
Transmission Cross-member
Along with the lower transfer case section, the
cast aluminum transmission cross-member is a
low profile design to optomize ground clearance.
Both manual and automatic transmissions
utilize the same part.
52
E46 Models
Transfer Case
The Transfer case for the E46/16 is the NV 124 manufactured by New Venture. The
primary difference between the NV 124 and the NV 125 used in the X5 SAV is that it uses
gears instead of a drive chain for torque transfer to the front axle.
The reason gears are used is to produce a
compact low profile transfer case that could
fit in the transmission tunnel of an E46 without excessively limiting the forward travel of
the drivers seat.
Manufacturer:
Type:
Torque Distribution:
Maximum Torque:
New Venture
NV 124
38%: 62%
300Nm
The transfer case is only one speed and
does not use any viscous coupler.
The transmission ratio of the planetary gear
set provides a fixed torque transfer of 38:62
(front:Rear). The output speeds to the front
and rear axle are the same (1:1).
The input to the Planetary
Carrier is from the output shaft
of the transmission.
The Sun Gear of the Planetary
assembly is turned by the
Planetary Gears, the Sungear
then provides torque to the
Transfer Gear.
Planetary Gear
Set
Planetary Carrier
Input
Transfer Gear
Output Gear to
The Transfer Gear drives the Front Axle.
Output via gear-to-gear
contact. The front axle is driven
via a flange connected to the
output gear.
Hole for Rubber
Mounting
53
E46 Models
Output to Rear Axle
Planetary Ring Gear
From the Ring Gear , the power is transmitted via the driveshaft to the rear axle differential.
Torque Transfer from the
Planetary Gear Set.
The transfer case is filled with a lifetime fill of
MTF-LT1 P/N 83-22-9-408-942. The only
repairs possible are the replacement of the
three oil seals and the hydraulic mount.
Oil Volume:
Drain/Fill plug torque:
54
E46 Models
0.24 liter
33Nm
Review Questions
1. How is the hood of an E46 placed into the workshop position?
2. Explain the door anchoring system of the E46.
3. Describe the fuse locations of the E46.
4. Describe the changes made to the E46 front and rear suspension from the previous
3 series (E36).
5. Where is the emergency release for the tailgate located on the E46 Sport Wagon?
6. What allows the windshield frame of the E46 Convertible to act as a roll over protection
device?
7. How is the floor pan on the E46 Convertible improved for structural rigidity?
8. Describe the components used in the E46 all-wheel drive running gear.
9. Describe the changes made to the front suspension of the E46 to accommodate the
all-wheel drive system.
55
E46 Models
Table of Contents
E46 DRIVER INFORMATION
Subject
Page
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
E46 Bus Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Instrument Cluster. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Check Control Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Range/Program Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
Dynamic Digital Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Analog Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Digital Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Output Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Redundant Data Storage. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
SIA IV. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
On Board Computer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Light Switch Center (LSZ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
E46 Convertible Third Brake Light. . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Lamp Monitoring. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
Home Lighting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Emergency Lighting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Xenon Head lights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
LWR- Headlight Beam Throw Control. . . . . . . . . . . . . . . . . . . . . . . . .35
Multi-Function Steering Wheel.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Initial Print Date: 6/98
Revision Date: 11/21/00
Introduction
The driver information system is presented to the driver in two main areas, the instrument
cluster and the center console area. The E46 makes extensive use of bussing for communication between control modules and reduction in wiring.
The instrument cluster in the E46 is similar in design to the basic cluster installed in the E39.
It uses the pictogram display block for check control and lamp failure warnings.
The Bus links used in the E46 include:
The K-Bus: For communication between all body modules and driver information systems.
The CAN Bus: For communication between the engine management control modules and
the instrument cluster.
The D-Bus: For diagnostic communication between the vehicle and the DIS and MoDiC
testers.
3
E46 Driver Information
E46 BUS SYSTEMS
BUS SCHEMATIC
A
Example Bus system as introduced.
4
E46 Driver information
E46iC BUS SYSTEM
The Bus system of the E46iC continues to use the K-Bus as the main communication link
between body and driver information modules. The Convertible Top Module (CVM) is added
to the K-Bus for communication with the GM V for top operation and the Instrument Cluster
for diagnostic purposes. The addition of memory functions for both outside mirrors has
required memory modules to control the operation. These modules are also connected to
the K-Bus for communication with the Seat Memory module.
As with other MRS III systems, the MRS module is now connected to the K-Bus for coding/diagnostic and communication with the other control modules.
CVM
EWS 3.3
C53
5
E46 Driver Information
SIGNALS WHICH ARRIVE AT THE INSTRUMENT
CLUSTER VIA THE K-BUS
INFORMATION ITEM
doors, trunk lid
driving light error
brake light error
turn signal control
turn signal synchronization
position light, dipped beam,
high beam, fog light
rear light error
ignition key
DME-S-AC, air condit.
Switch
DME-LSZ-KK, load torque
air conditioning
transfer, km reading
reset BC function
distance display,SA 9/98
SOURCE
RECIPIENT
basic module
light-switch center
light-switch center
light-switch center
light-switch center
light-switch center
instruments
instruments
instruments
instruments
instruments
instruments
light-switch center
electronic immobilizer
IHKR
instruments
instruments
instruments
IHKR
instruments
light-switch center
on-board monitor/navigation computer
on-board monitor/navigation computer
instruments
instruments
instruments
SIGNALS WHICH ARRIVE AT THE INSTRUMENT
CLUSTER THROUGH THE CAN-BUS
INFORMATION ITEM
engine speed
fuel consumption
coolant temperature
outdoor temperature
selector lever position
gear program
transmission malfunction display
ASC indicator lamp
Check-Engine
FGR indicator lamp - cruise
EBV indicator lamp
fuel tank level
VIN
6
E46 Driver information
SOURCE
DME/DDE
DME/DDE
DME/DDE
instruments
AGS
AGS
AGS
ASC
DME/DDE
DME/DDE
ASC
instruments
instruments
RECIPIENT
instruments
instruments
instruments
IHKA
instruments
instruments
instruments
instruments
instruments
instruments
instruments
DME
LWS
INSTRUMENT CLUSTER
The instrument cluster uses analog gauges for display of engine and road speed, engine
temperature, fuel level and economy display.
There are three LCD blocks for display of:
80
100
40
12
0
11
20
3
100
60
2
120 140
160
180
80
60
200
40
220
240
20
4
5
1/min
x1000
120
6
1
140
UNLEADED GASOLINE ONLY
km/h
0
50 30 20 15
7
12
MPH
• The check control - pictogram
• The BC/Service interval and mileage
• The Transmission - range/program and failure display
Warning indicators and lamps are arranged to the right and left of the LCD blocks. The
ASC, charge indicator, high beam and oil pressure lamps are located between the
speedometer and tachometer.
Features of the E46 cluster include:
• Stepper motor drives for the analog gauges
• New design Service Interval Indicator (SIA IV)
• Automatic transmission range/program display
The instrument cluster is a sealed unit and contains no serviceable components, other than
the back lighting illumination bulbs.
7
E46 Driver Information
CHECK CONTROL LCD MATRIX DISPLAY
The pictogram check control display carries over from the E39 for failure display warnings
of various lights, doors/trunk open and low fluid indications. Inputs for warning lamp indication are processed by the cluster electronics and the appropriate LED is illuminated.
RANGE/PROGRAM MATRIX DISPLAY
The right LCD matrix is used to display the driving range and program on vehicles equipped
with an automatic transmission. The transmission fault display is also integrated into the
display matrix. The gear with the explanation point will illuminate when the electronic control of the transmission detects a fault.
8
E46 Driver information
DYNAMIC DIGITAL INPUTS
DISTANCE SIGNAL- This input is supplied to the cluster by the ABS/ASC+T control module as a square wave signal. Pulses from the left rear wheel speed sensor are processed
by the ABS module to produce this signal. The cluster electronics process the input for the
cluster display and pass the signal along, on the K bus, as speed signal “A” for other control modules requiring the vehicle speed signal.
CAN BUS SIGNALS- The “Ti” , engine temperature and “TD” signals are produced by
the DME control module and sent to the cluster. The cluster also passes the TD signal
out over the K Bus.
TRANSMISSION DATA- The AGS control module provides the range selector position,
driving program and fault lamp activation signals to the cluster over the CAN line.
DSC
CAN
OIL TEMPERATURE - This input is a pulse width modulated signal from the Electronic Oil
Level Sensor. As oil level decreases the pulse width of the signal increases. If the signal
shows an oil level that is too low over a period of time, the instrument cluster will illuminate
the Oil Warning indicator LED in yellow.
DIMMER SIGNAL - This is a pulse-width modulated signal from the LSZ. It is used to control the intensity of the back lighting of the instruments and the LCDs when the lights are
switched ON. This signal is also output over the “K” Bus.
K-BUS SIGNALLING - The Cluster receives signals for the Check Control Pictogram over
the K-Bus.
9
E46 Driver Information
ANALOG INPUT SIGNALS
BATTERY VOLTAGE - Battery voltage is monitored by the cluster and a fault is stored if
the voltage exceeds 16 volts
FUEL TANK LEVEL - Two lever action sensors are wired in parallel to the cluster. The two
varying voltage signals are processed by the cluster for fuel gauge and low fuel warning
display.
OUTSIDE TEMPERATURE SENSOR - A NTC sensor is used to measure the ambient
temperature. The signal is processed by the cluster and passed out over the K Bus to modules requiring this input for processing.
10
E46 Driver information
DIGITAL INPUT SIGNALS
The normal ignition switch terminals (KL R, KL 15 & KL 50) are input to the cluster. Various
functions are dependent on ignition switch position.
STEERING COLUMN SWITCH - As with previous systems the turn signal stalk is used to
call up BC functions.
BRAKE PAD WEAR SENSORS - The pad sensor inputs are used to illuminate the brake
pad warning indicator as in the past.
INSTRUMENT PANEL BUTTON - The reset button is used to reset the trip - odometer
as in the past. It will also display the mileage, if pressed with the key switched OFF. This
button is also used for the Base BC/instrument cluster test functions outlined on page 15.
INPUTS FOR WARNING LAMPS - Various switches are used to signal the cluster for
warning and indicator lamp illumination including:
WARNINGS FOR CONVERTIBLES
• The seat belt warning lamp is illuminated when the seat belt is not fastened and
FLASHES when the front seat back is not locked into position.
• The Roll over Protection System warning lamp is illuminated when there is a fault in the
RPS system.
11
E46 Driver Information
OUTPUT SIGNALS
SPEED SIGNAL “A” - The vehicle speed signal is available as an output for control modules that require precise vehicle speed information.
“K” BUS INTERFACE - The K Bus is used to transfer data between the cluster and other
modules on the link. The diagnostic interface also passes over the K Bus for troubleshooting with the DIS Tester.
LOW FUEL - Based on the processing for the low fuel indicator lamp, this output is also
sent to the DME control module. The signal is stored along with a mis-fire detection fault
for troubleshooting purposes.
GONG OUTPUT - T3, The T3 tone is used for check control warnings.
12
E46 Driver information
REDUNDANT DATA STORAGE
Specific information is stored redundantly in the instrument cluster and in the Light Switch
Module. The data stored redundantly includes:
• VIN
• Total Mileage
• Service Interval data
VIN
VIN
TOTAL MILEAGE
TOTAL MILEAGE
SERVICE INTERVAL
INFORMATION
SERVICE INTERVAL
INFORMATION
80
The redundant storage
of this information allows
for the replacement of a
module without the loss
of the total mileage
accumulated or the loss
of the SI data.
100
40
12
0
11
20
3
100
60
K-BUS
2
120 140
160
180
80
60
200
40
220
240
20
UNLEADED GASOLINE ONLY
km/h
4
5
1/min
x1000
120
6
1
140
0
50 30 20 15
7
12
MPH
LSZ
MANIPULATION DOT
The data is compared each time KL 15 is switched on. If the data does not match, the
manipulation dot in the mileage display block will be illuminated.
The following points must be noted with regards to the redundant storage of this data.
1. If the vehicle ID number is not the same in both modules, the manipulation dot is illuminated. All functions of both modules continue to operate.
2. Data will only be transferred from the LSZ to the cluster if the ID numbers match and the
cluster mileage is zero.
3. The VIN is entered in the cluster through coding and will only be accepted when the cluster mileage is zero.
4. The stored mileage in the LSZ can only be overwritten by a higher mileage.
5. If the two mileage values stored vary by more than 120, and the VINs are the same, the
cluster will continue to accumulate mileage and a fault will be stored in the cluster for
data transfer.
6. If the K-Bus link fails, the cluster will continue to store mileage and set a fault for the Bus
link.
New components should only be installed for replacement purposes and not for use as test
components for diagnosis as miles will accumulate if the vehicle is driven for road testing
purposes.
13
E46 Driver Information
14
E46 Driver information
SIA IV
Models: E46
Production: From start of production
80
0
UNLEADED GAS OLINE ONLY
120 140
100
160
80
180
60
20
2
4
5
1/min
x1000
120
1
200
40
11
3
100
60
40
12
6
220
240
20
140
0
km/h
5030 20 15
7
12
MPH
Made in Germany
Mmiles
OILSERVICE
15000
Miles
SIA IV Components:
•
Instrument Cluster with LED display
•
DME
•
Vehicle Speed Signal
Instrument Cluster (IKE, KOMBI) with LED Display
The Instrument cluster calculates the Service Interval. The cluster is also responsible for
displaying the mileage reading for the next service.
DME
The DME provides the Fuel Consumption (ti) signal.
ASC/DSC Control Module
The vehicle speed signal is provided by the ASC or DSC control module.
15
E46 Driver Information
Principle of Operation
Starting with the E46 a new method for displaying
the Service Interval is used. Colored LEDs are no
longer used to display the amount of time until the
next service or inspection is due.
With the SIA IV system, the actual mileage remaining until the next service will be displayed for five
seconds when the ignition is first switched on.
OILSERVICE
15000
Miles
The text “OIL SERVICE” or “INSPECTION” will also illuminate to show which service is due.
A minus symbol( - ) before the mileage display indicates that a service is past due.
The calculation process for determining the service interval is similar to SIA III. A set
volume is stored in the Cluster. The processor receives the ti signal from DME as the vehicle is driven. The Cluster also receives the vehicle speed signal from the ASC/DSC control
module.
Based on the amount of fuel consumed and the distance traveled, the processor calculates
the distance remaining to the next service.
Workshop Hints
Reset of the SIA can be done using special tool 62 1 110 if the vehicle is equipped with the
20 pin under-hood diagnosis connector.
On 2001 MY vehicles onward without the diagnostic connector in the engine compartment,
the use of the S.I reset tool is not possible. The Service Indicator may be reset using the
Reset Mode in the Instrument Cluster or with Diagnosis.
16
E46 Driver information
Reset procedure using the Reset Mode. (possible from 9/99 onward for E46, MY2001 E52)
•
Ignition key must be “off”
•
Press and hold the trip odometer button in the instrument cluster (left button), and turn
the ignition key to the first position (KLR).
•
Keep the button pressed for approximately 5 seconds until one of the following words
appear in the display: “OIL SERVICE, or “INSPECTION”, with “reset”.
•
Release the reset button and press and hold it again until “reset” begins to flash.
•
While the display is flashing, press the left button briefly to reset the service interval.
After the display has shown the new interval, the following will appear: “END SIA”
The system can only be reset again after 10 liters (2.5gal) of fuel have been consumed.
1
2
80
40
12
0
PRESS AND
HOLD LEFT
BUTTON
100
80
20
2
120 140
160
180
60
4
5
1/min
x1000
120
6
1
200
220
40
11
UNLEADED GASOLINE ONLY
3
100
60
240
20
140
0
km/h
50 30 20 15
7
12
MPH
TURN KEY TO POSITION
1 (KLR)
Mmiles
ESET
SIA
OILSERVICE
15000
KEEP
PRESSED
FOR 5 SECONDS
AFTER KEY IS
SWITCHED ON.
END
SIA
Miles
E46 service interval reset
TAP BUTTON TO
RESET SI DISPLAY
17
E46 Driver Information
Reset using Diagnosis Program
• Connect the Diagnosis head to the diagnostic connector of the vehicle.
•
Identify the vehicle and perform the Short Test.
•
Select Function Selection and then Service Functions.
• Highlight Reset Service Interval Indicator (Test module S6211-00001)
•
Select with tester.
•
Follow the directions from the help information in the test module (upper right corner).
•
Select which service is to be reset and press the continue key.
•
An acknowledgement is displayed on the screen that the reset has been carried out.
Instrument Cluster Replacement
If the instrument cluster (Kombi) is replaced the SI data can be retrieved from the LSZ on
E46 vehicles and from the LCM III on the E52. Coding procedures are the same as SIA II.
Diagnosis
Diagnosis of the SIA System is carried out using the Diagnosis program of the DISplus or
MoDiC III.
System Test: Also possible
from the Instrument Cluster Self
Test, the Display Test illuminates
the Service Interval Display. To
enter the test:
• Function Selection
• Service Functions
• Body
• Instrument Cluster
• System Test
• Test Schedule
Read
SIA Data:
Displays
Instrument cluster data as well as
SIA data. SIA data allows the technician to verify that the SIA system
is using the proper calculation as
well as viewing the current status
of the system. To enter
• Function Selection
• Service Functions
• Body
• Instrument Cluster
• Service Interval Indicator Data
• Test Schedule
Test Modules: Problems with the SIA System can be diagnosed
using fault or Symptom driven test modules. To begin diagnosis:
• Short Test
• Select Symptom from Symptom selection page
• Select Test module from Test Plan Page
• Test Schedule
18
E46 Driver information
ON BOARD COMPUTER
The On Board computer of the E46 contains the following functions:
•
•
•
•
•
Time
Outside temperature
Average fuel consumption
Driving range on remaining fuel
Average speed
The current time is always displayed when KL R is switched on. Any other BC display value
can be called up by pressing the turn signal lever.
To set the clock “turn” the odometer reset button to the left or right to set the desired time.
To reset any other programmable displays - hold the turn signal lever in for > 2 seconds.
A freeze warning is incorporated into the BC. If the temperature drops below 37 degrees,
the gong will sound and the temperature display will flash.
The displays of the Board computer can be changed over from Fahrenheit to Celsius by
pressing the instrument cluster button and switching the ignition key on. IHKA display will
also change over. The average fuel consumption and average speed displays are reset by
pressing and holding the turn signal lever for > 2 seconds. The BC then starts to calculate
new average values.
19
E46 Driver Information
INSTRUMENT CLUSTER TEST FUNCTIONS
In addition to the fault memory and diagnostic link, the base instrument cluster contains a
series of test functions that can be accessed to check various functions and values. The
test functions are displayed in the mileage LCD block. There are a total of 21 test functions.
The test functions are similar to those of previous Board computers and contain similar
tests.
•
•
Tests 1 & 2 are always unlocked.
Tests 3 -21 are only accessible after unlocking the test function. Test 19 is the unlock
function for accessing the displays.
Scrolling through the
numbered test functions is achieved by
pressing the instrument cluster button.
The button is either
momentarily pressed
(tapped) < 1 second
or pressed and held
for > 1 second.
This signals the BC to
display the sub-tests
of the displayed main
test menu or continue
on to the next main
test menu.
20
E46 Driver information
TEST 01. - Vehicle specific data including:
SubTests:
12345
1.0 = VIN
4812
1.1 = Body number
834762 6_1.2 = Part number of cluster
010203 1.3 = Coding/Diagnosis/Bus index
3495
1.4 = Manufacturing date (calendar week/year)
04_600 1.5 = Hardware/software # of cluster (HW:04, SW:6.00)
415_06 3_1.6 = Injection status, number of cylinders, engine factor
TEST 02. - Cluster System Test - activates the gauge drivers, indicators and LEDs to confirm function.
TEST 03. - SI data
Sub Tests:
1500
3.0 = Liters
0
3.1 = Periodic inspection days (not applicable for US).
TEST 04. - Momentary Consumption
Sub Tests:
0267
4.0 = 26.7 liters/1000km
0073
4.1 = 7.3 liters per hour
TEST 05. - Distance Gone Consumption
Sub Tests:
0195
5.0 = 19.5 liters/100 km
226
5.1 = momentary distance to go (226km)
TEST 06. - Fuel level sensor inputs in liters
Sub Tests:
237415 6.0 = Fuel level averaged
• LH sensor input = 23.7 liters
• RH sensor Input = 41.5 liters
0652
6.1= Total tank level averaged = 65.2 liters
0667
1_6.2 = Indicated value and tank phase • 1 = both sensors OK
• 2 = one sensor fault
• 3 = implausible input
21
E46 Driver Information
TEST 07. - Temperature and Speed
Sub Tests:
032
7.0 =
245
7.1 =
5283
7.2 =
058
7.3 =
Coolant temp input 32OC
Outside temp input 24.5OC
Engine speed 5,283 RPM
Vehicle speed 58km/H
TEST 08. - Input values in HEX form
Sub Tests:
XXX
8.0 - 8.3 = Hex code, Instrument cluster inputs
TEST 09. - Battery voltage
Sub Test:
125
9.0 = 12.5 volts
TEST 10. - Country Coding
Sub Test:
02
10.0 = US 02
TEST 11. - Cluster code
Sub Test:
000003 11.0 = Cluster code
TEST 12. - Not Used
TEST 13. - GONG test
Sub Test:
Gong
13.0 = Activate gong by pressing button (gong response is delayed).
TEST 14. - Fault memory (not for diagnosis)
TEST 15 to 18 - Not used
22
E46 Driver information
TEST 19. - LOCK/UNLOCK
Sub-Tests
L-ON...
L-OFF 19.0 =
Display changes from “L-ON” to “L-OFF” every second. To unlock test functions, press
the cluster button immediately when it changes to “L-OFF”.
Tests are automatically locked when exiting test functions.
TEST 20. - Not Used
TEST 21. - Software reset
Sub-Test:
reset
21.0
= Reset software
23
E46 Driver Information
LIGHT SWITCH CENTER (LSZ)
The Light Switch Center is a compact component that combines the electronic control,
switching, and monitoring for all exterior lighting on the E46. In addition the LSZ controls
the illumination and intensity of the instrument cluster lighting and LCD blocks. The LSZ
assembly is mounted in the dash and consists of two serviceable components; the
switch assembly and the control module.
LSZ
The LSZ provides the functions of the LCM including:
•
•
•
•
Hot and cold monitoring of the exterior lights.
Emergency lighting function
Short circuit protection
Redundant storage of mileage and SI data
The total scope of the LSZ system includes the following:
•
•
•
•
•
•
•
•
LSZ control module
LSZ switch assembly
High-low beam/turn signal switch
Brake light switch
Hazard warning light switch
Fog light relay
Exterior lights
Dash/LCD lighting
LSZ
BULB MONITORING
BULB ACTIVATION
80
100
GM V
AGS
24
E46 Driver information
K-BUS
11
20
2
120 140
160
180
80
60
200
40
220
240
20
UNLEADED GASOLINE ONLY
km/h
MPH
DATA LINK
3
100
60
40
12
0
4
5
1/min
x1000
120
6
1
140
0
50 30 20 15
7
12
COMPONENT OPERATION
The LSZ control module receives inputs from the following switches:
Headlight/parking light switch, fog light switch, potentiometer and photo-transistor mounted in the LSZ switch assembly.
• These inputs are received directly from the LSZ switch assembly.
TURN SIGNAL/HIGHBEAM SWITCH
• The turn signal and headlight (high/low) beam are resistance coded inputs over two wires
to the LSZ control module. The LSZ carries out the switching function based on the voltage drop input.
HAZARD WARNING SWITCH
• The hazard switch provides a ground input to the LSZ to control the operation of the hazard warning lights.
• The hazard warning lights will be switched on in the event of an accident from the crash
sensor input provided by the MRS control module.
BRAKE LIGHT SWITCH
• The brake light switch is a hall sensor that receives power when KL R is switched on. The
switch is low until the brake pedal is pressed. When the LSZ receives a high signal from
the switch the brake lights are switched on.
• If the hall sensor fails, the brake lights will be switched on continuously.
25
E46 Driver Information
E46 Convertible Third Brake light
The E46iC uses Neon technology for the third brake light which is mounted in the trunk lid.
The remainder of the exterior lighting circuits carry over from the E46 Sedan and
Coupes.The Electronic brake light switch is the input to the LSZ for brake light activation.
The LSZ, as an output, provides power to the Neon light module for activation of the light.
The light module consists of the ignitor, and Neon tube.
The use of neon lighting provides several advantages
to automobile manufacturers and consumers:
Light failures caused by shock and vibration are minimized,
because neon operates without a filament.
The average life of the light is considerably higher as
compared to incandescent bulbs.
Styling of the light includes a more uniform distribution of
light across the lens, and neon tubes can be bent to
conform to the contour of the vehicle.
Amber neon allows the use of a clear lens (for vehicle color
schemes).
Neon enhances safety because of the extremely fast ignition time of the light (instantaneous braking signal), allowing
other drivers more time to react.
Neon Technology
Neon (symbol Ne) produces a glow in
a vacuum electric-discharge tube and is used extensively in the familiar advertising displays.
A neon light is a glass bulb or tube containing neon (gaseous element) at low pressure,
and two metallic electrodes. To make a neon light, the tube is bent while warmed, to the
desired shape and sealed at both ends. During the sealing process, electrodes are added
at each end. An access port is left near one end and a vacuum is applied to the interior
of the tube. After the air and humidity has been removed, the neon gas is added under
low pressure and the tube is sealed.
The light produces a reddish-orange glow when an electric current (applied across the
electrodes) is raised in voltage to the point at which it ionizes the gas in the tube. The
voltage at which the light glows varies with the design of the tube. When the glass tube is
ionized, the voltage drop across the tube is constant, regardless of the amount of current
flowing through the tube. The neon glows with an even intensity throughout the length of
the tube.
A variant of this is the glass tube containing ionized neon at very low pressure. The tube
shines with a brilliant red glow if a high-voltage alternating current is applied to the electrodes sealed in the ends of the tube.
26
E46 Driver Information
LAMP MONITORING
Lamp monitoring on the E46 is a function of the LSZ control module. The following lamps
are monitored in both the hot and cold states:
•
•
•
•
•
•
•
High/low beams
Brake lights - left/right
Turn signal lights
Tail lights
Parking lights
Side marker lights
License plate lights
Hot monitoring takes place when the lights are switched by monitoring the current flow
through the lamp filaments.
Cold monitoring takes place by the LSZ when the lights are switched off. The LSZ will briefly
activate the lighting circuits and check for current flow through the lamps. The lights are not
switched on long enough to illuminate the bulbs.
If the LSZ detects a defective bulb, a signal is sent to the instrument cluster and the warning is posted in the Check Control pictogram.
27
E46 Driver information
HOME LIGHTING
This convenience feature provides lighting for the driver and passengers to leave the vehicle and enter their house.
The feature is switched on by activating the headlight flasher switch after the lights and ignition are switched off.
The feature is switched off after the coded time delay or by switching the ignition switch on.
REDUNDANT STORAGE
The LSZ serves as the redundant storage module in parallel with the instrument cluster.
This includes all data used for vehicle identification which is encoded on the assembly line.
In addition the total mileage and SI data are also stored in the LSZ.
If either the Cluster or LSZ has to be replaced, the data is taken from the remaining module and transferred to the replacement unit. This can only occur ONCE the VIN has been
entered into the replacement unit. Once the VIN is entered, the module becomes part of
the vehicle and can not be interchanged with another vehicle.
28
E46 Driver information
EMERGENCY (FAIL SAFE) LIGHTING
The LSZ provides emergency lighting in the event of a control module failure. If the processor of the LSZ control module fails, back up hardware will allow the following lighting circuits to function:
•
•
•
•
Low Beam headlights
Tail lights
Parking Lights
Brake Lights
The headlights and tail lights will come on as soon as KL 15 is switched on, the brake will
operate when the brake pedal is pressed.
29
E46 Driver Information
XENON HEADLIGHTS
OVERVIEW
The automotive industry/press often identify xenon lighting systems as HID (high intensity
discharge) systems. Xenon headlight technology was first introduced to the US market
exclusively on the E32 750iL in 1993. BMW xenon headlight systems have evolved and
their availability as optional equipment has spread throughout the model lineup.
Blue/White in color and using ellipsoidal technology Xenon headlights provide improved
night time visibility in all driving conditions compared with traditional Halogen bulb headlights.
BENEFITS:
Xenon headlights provide the following benefits:
•
Longer bulb life. Typically, xenon bulbs will last from 3 to 5 times longer than halogen.
•
More light output. Xenon headlights produce from 2.5 to 3 times more lumens than
halogen.
•
Blue/White light (simulates natural daylight). Xenon bulbs produce a blue/white light
while halogen bulbs produce a yellow light. The light color of a light source is measured
in color temperature (not to be confused with thermal temperature). Color temperature
is measured in Kelvins (K). The higher the color temperature the whiter the light.
Natural daylight = 4,500 to 5,000 K
Xenon headlights = 4,000 to 4,500 K
Halogen headlights = 3,200 K (yellow in color)
•
Better driving visibility.
The combination of higher
lumens and higher color
temperature provide a superior lighting source.
The beam is wider and
brighter in front of the vehicle than conventional halogen bulbs improving safety
and driver comfort.
30
E46 Driver Information
VERSION IDENTIFICATION & SYSTEM SUMMARIES
Version identification is specific to vehicle model with the exception of the E38.
There are two E38 Xenon systems. The early system identified as Generation 2.1 and equipped on
95-98 model year 750iL vehicles. The headlight
design of this version has a flat bottom edge.
The Generation 3 system has been introduced on
1999 model year E38 vehicles. This system can be
visually identified by the rounded bottom edge of
the headlight assembly.
E46 Headlight
LWR: All 1999 model year systems are also equipped with LWR (Headlight Beam Throw
Control). This system automatically adjusts the vertical position of the headlight beams to
compensate for vehicle loads ensuring optimum beam throw. LWR components and function is described further on in this section.
Headlight Replacement Parts: In previous model years, individual replacement parts
were not available for headlight assemblies. This was due to the Federal Motor Vehicle
Safety Standards (FMVSS) relating to pitting or corrosion of the reflector components in
non-sealed beam light assemblies.
BMW has submitted corrosion test data for headlight replacement components which have
passed the FMVSS providing availability of headlight assembly spare parts. The approval
has been given for all Bosch headlight assemblies (including halogen systems).
Vehicle/
Model
Model
Year
Manufacturer(s)/
Version ID
LWR- Head
Light Beam
Throw Cont.
Individual
Replacement
Parts Available
E32/
750iL
93-94
Hella (Light &
CM ”control module”)
Generation 1
No
No
E38/
750iL
95-98
Bosch (Light & CM)
Generation 2.1
No
Yes
E38/
All
99-
Bosch (light)
Hella (CM)
Generation 3
Yes
Yes
E39
All
99-
Hella
Generation 3
Yes
No
E46
99-
Bosch (Light & CM)
Yes
Yes
31
E46 Driver Information
XENON HIGH INTENSITY DISCHARGE BULBS
Xenon bulbs are identified as D-2S (D=Discharge).
Xenon bulbs illuminate when an arc of electrical current is established between two electrodes in the bulb.
The xenon gas sealed in the bulb reacts to the electrical excitation and heat generated by the current flow.
The distinct bluish/white brilliant light is the result of the
xenon gas reacting to the controlled current flow.
Phases of Bulb Operation:
Starting Phase: The bulb requires an initial high voltage starting pulse of 18-25kV to establish the arc.
Warm Up Phase: Once the arc is established the power supply to the bulb is regulated to
2.6A generating a lamp output of 75 watts. This is the period of operation where the xenon
gas begins to brightly illuminate. The warm up phase stabilizes the environment in the bulb
ensuring continual current flow across the electrodes.
Continuous Phase: Once the warm up phase is completed, the system switches to a continuous mode of operation. The supply voltage for the bulb is reduced and the operating
power required for continual bulb illumination is reduced to 35 watts which is less than a
conventional halogen bulb.
FUNCTIONAL DESCRIPTION
To regulate the power supply to the bulbs, additional components are required. The xenon
control modules (1 per light) receive operating power from the lighting control module (LCM
E38/E39 -- LSZ E46) when the headlights are switched on. The xenon control modules provide the regulated power supply to illuminate the bulbs through their phases of operation.
The igniters establish the electric arcs. Integral coils generate the initial high voltage starting pulses from the control module provided starting voltage. Thereafter they provide a
closed circuit for the regulated power output from the control modules.
32
E46 Driver Information
XENON BULB MONITORING
Xenon bulb function is monitored by the Lighting Control Module (LCM E38/E39 -- LSZ
E46). The bulbs are only “hot” monitored. Cold monitoring is not possible since the lighting control module is not in direct control of the xenon bulb. For this reason cold monitoring for low beam headlights is encoded off in the lighting control module for Xenon headlight equipped vehicle.
The lighting control module detects xenon bulb failure via a reduction in current flow to the
xenon control module. When a bulb fails, the xenon control module’s current consumption
drops to 60mA indicating unsuccessful xenon bulb illumination. The lighting control module then posts the appropriate matrix display message or LED illumination in the Check
Control Pictogram display of the E46 and E39 Low Instrument Clusters.
XENON HEADLIGHT ASSEMBLY COMPONENTS (Example - E46)
Xenon Control
Module Cover
H-7 Halogen Bulb
(High Beam)
Rubber Cover Boot
Xenon Control Module
LWR Stepper Motor
Igniter
Gasket Seal
D-2S Xenon Bulb
(Low Beam)
Light Frame Assembly
Replaceable Lens Cover
33
E46 Driver Information
DIAGNOSIS
Xenon control modules are not connected to the diagnostic link. However, the vehicle specific Lighting Control Module (E38/E39 - LCM or E46 - LSZ) does incorporate xenon headlight specific diagnosis up to the xenon control module.
XENON HEADLIGHT TESTING
Warning: Xenon headlight control systems generate high output voltage. Prior to headlight removal or testing observe the vehicle warning labels and be cautious by following
safeguards to prevent accidental injury.
All xenon headlight systems (control
module, igniter and bulb) can be tested with Special Test Adapter (P/N 90
88 6 631 000) in conjunction with the
DIS Measurement System only.
Refer to SI 04 33 96 for detailed
adapter introductory information.
The DIS Measuring System includes all
of the cable connection information
and test procedures in the “Xenon
Preset Measurement”.
The test provides an automatic oscilloscope setup and provides conclusive “defective/not
defective” test results.
XENON HEADLIGHT SI/TRI BULLETINS
• SI 6308 98: Xenon Headlamp Reduced Service Life - 1999 740iL. This bulletin address
a small group of possibly defective xenon control modules. This bulletin uses the special test adapter and specific oscilloscope setup procedures to check the xenon control module output.
•
SI 63 02 98: E39 Headlight Alignment Procedure
•
SI 63 02 93: Xenon Headlights - Color, Fuses, Warranty
•
TRI 63 01 92: Gas Discharge Xenon Low Beam Headlights.
34
E46 Driver Information
HEADLIGHT BEAM THROW CONTROL- LWR
OVERVIEW
LWR automatically adjusts the vertical positioning of the headlights to maintain optimum
headlight beam positioning for maximum driving visibility and to prevent undue glare for
oncoming motorists. The system compensates for vehicle load angle changes (ie: diminishing reserve of gasoline in fuel tank during a long journey, overloaded cargo weight, etc.)
LWR has been available on BMW vehicles in other markets for quite some time. Starting
with the 1999 model year all US market vehicles with Xenon Lights incorporate LWR as
standard equipment. LWR is not available with standard halogen headlights.
LWR monitors the vehicle’s loaded angle via two hall effect sensors mounted to the front
and rear suspension members. When an adjustment is necessary, LWR simultaneously
activates two stepper motors (one in each headlight assembly).
The stepper motors drive a threaded rod that moves the lower edge of the headlight carrier plate forward and backward (depending on driven direction). The upper edge of the
headlight carrier plate is fixed on a pivot. The pivoting movement adjusts the vertical position of the headlight beam.
Note: LWR is identified in the Diagnosis Program as LRA.
35
E46 Driver Information
LWR COMPONENTS
CONTROL ELECTRONICS
LSZ - E46
The E46 LWR function is integrated into the control electronics of the LSZ. The LSZ monitors the required input signals to provide the LWR function and directly activates the stepper motors in the headlight assemblies. All LWR diagnosis is accessed through the LSZ
control module.
LEVEL SENSORS
LWR monitors two hall effect level sensors to
determine vehicle load angle. The sensors
are mounted to a fixed point on the suspension carriers of the front and rear axles.
A lever is connected to the moving suspension member which changes the sensors output linear voltage signal as the suspension
moves up and down.
HEADLIGHT ADJUSTMENT STEPPER MOTORS
One stepper motor is located inside each
headlight assembly.
The 4 wire stepper motors are controlled
by the LWR control electronics to change
the vertical headlight position.
36
E46 Driver Information
FUNCTIONAL DESCRIPTION
The E46 LWR system comes on-line when the ignition switch is turned to KL 15.
The LWR control electronics then cycles the stepper motors through their full range of
motion and stops at a default position.
The control electronics monitors the level sensor input signals to determine the vehicles
load angle and adjusts the beam position accordingly. As the vehicle is driven it continually monitors the level sensor signals and if necessary updates the headlight beam positions
every 25 seconds.
Abrupt fluctuations of the sensor signals are filtered to prevent unnecessary adjustment as
well as monitoring road speed.
HEADLIGHT ALIGNMENT
The procedure for aligning Xenon Headlights with LWR is the same as conventional halogen bulb systems with one additional step. Wait at least 30 seconds for the LWR to cycle
and adjust to it’s calculated position.
LWR DIAGNOSIS
The E46 LSZ incorporates LWR diagnosis program.
LWR SYSTEM IPO SCHEMATIC
37
E46 Driver Information
MULTI-FUNCTION STEERING WHEEL
The multi-function steering wheel of the E46 corresponds to the MFL introduced on the E38
and carried over to the E39. The wheel contains two key pads on the left and right side of
the air bag that allow activation and control of various driver convince systems.
As with previous MFLs, the left side key pad contains controls for the sound system and
telephone. The right side key pad contains the controls for the cruise control.
The K-Bus is used for data communication between the sound system/telephone controls.
The cruise control has its own data link to the DME control module for cruise control operation.
38
E46 Driver information
Subject
Page
Sound Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Sport Wagon Sound System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Convertible Sound System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
NG Radio. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Radio Removal Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
E46 Mark 2 Navigation System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Navigation Service Mode Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Navigation System Calibration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Navigation System Diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
MK 3 Navigation System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
System Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
Navigation Computer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
GPS Receiver. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Gyro Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
GPS Antenna. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Display Units. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Information/Body Bus Interface. . . . . . . . . . . . . . . . . . . . . . . . . . 66
Video/Audio Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
Speed Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Reverse Gear Input. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Principle of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .71
Park Distance Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
SOUND SYSTEMS
Two different sound systems were available for the E46 at the start of production. The standard radio features the in-dash cassette player and the optional radio has a single in-dash
CD player. Both radios are prewired for the optional CD changer that mounts in the trunk.
The sound systems for the E46 continue with the integration feature introduced with the
E38. The sound system is interconnected on the K-Bus for amplifier and MFL communication.
Theft proofing of the radio via a code is no longer required as the radio will not function without the K-Bus connection and a valid K-Bus signal from the instrument cluster.
39
E46 Driver Information
E46 Sport Wagon Sound System
Antenna Configuration
The sound systems available for the E46 Sport
Wagon are the same as the systems installed in
the E46 Sedan and Coupe. The following antenna layout is used for the Sport wagon body:
• FM 1 - Rear window on the right side
• FM 2 - Rear window in the center
• FM 3 - Left rear side window
• AM - Rear spoiler
• FZV - Combined with FM 2 antenna
The amplifier for FM 1 and FM 2 antennas is
located beneath the rear spoiler. The signal from
the antennas passes from the amplifier to the
diversity module located in the left side storage
compartment.
40
E46 Driver Information
66460002
SOUND SYSTEM
Antenna Configuration
The FM 3 antenna has a separate amplifier that is integrated into the diversity
module which is mounted behind the
storage cover on the left side.
66460003
Diversity Switching
The FM1/FM2 amplifier can only send one FM
signal at a time. The diversity module controls
the switching of the signals by applying a voltage signal to the RF cable. When the voltage
signal is low, the amplifier sends the FM 1 signal. When the voltage level is high, it sends the
FM 2 signal. The FM 1 and FM 2 inputs are
continuously checked for the clearest signal.
The diversity module then checks the signal
from FM1/FM2 with the signal from FM 3. The
clearest of these signals will always be sent to
the radio for FM reception.
FZV Antenna
The RF receiver module (315MHz) is integrated into the antenna amplifier. The receiver has
a separate KL 30 power supply for its operation. Signal from the FZV key are processed by
the module and sent to the GM for locking/unlocking functions over a dedicated line.
41
E46 Driver Information
AUDIO SYSTEM SPEAKERS
The rear speakers for the sound system are mounted on the left and right wheel housing
behind the trim covers
If the Navigation system is installed in the Sport Wagon, the GPS receiver module is
installed under the load floor in front of the spare tire well.
GPS RECEIVER MODULE
42
E46 Driver Information
Convertible Sound System
The audio systems available for the E46iC correspond to the systems available in the E46
Coupe. Two radios, with either the in dash CD player or cassette player are available. The
navigation system with the board monitor is optional equipment. All sound systems are prewired for the optional CD changer that mounts in the trunk. The sound systems continue
to be interconnected on the K-Bus and all radio test functions carry over.
ART-BAYERN1
ART-BAYERN2
84E46NAVG0000
43
E46 Driver Information
HARMAN/KARDEN SOUND SYSTEM
Speaker and component locations will
vary depending on the type of sound
system installed. Four rear speakers are
mounted in the rear side trim panels, two
on each side (one wide band 130 mm
and one tweeter dome).
ART-KT4949
The Harman/Karden system incorporates an additional Subwoofer is
installed in the trunk in the ski bag cover.
The subwoofer is 200 mm diameter
without a subwoofer amplifier. The
amplification for the subwoofer comes
from the main sound system amplifier.
ART-KT5281
The subwoofer is hinged so that it will
swing to the side when the ski bag is
used. A magnet on the subwoofer cover
will hold the subwoofer in place against
the rear bulkhead while the ski bag is
being used.
The subwoofer will continue to function
in either position closed/open.
As mentioned , with the Harman/Karden
ART-KT5280
system, the stereophonic sound is modified when the top is lowered. The sound system amplifier receives a signal from the rear
window defroster relay when the top is lowered to switch the stereophonic sound off.
44
E46 Driver Information
ANTENNAS/DIVERSITY
Purpose of the System:
The E46iC is equipped with a diversity antenna system to provide the sound system with
the strongest possible radio station signal to receive the best performance possible from
the sound system.
Components of the System:
The Diversity antenna system on the E46iC consists of:
•
•
•
•
•
Main antenna mast - mounted on the left rear fender.
Diversity antenna - mounted in the top storage cover.
Main antenna amplifier - mounted directly below the antenna mast
Auxiliary antenna amplifier - mounted on the top storage cover.
Diversity switching module - mounted below the antenna mast in the trunk.
The telephone antenna is wound around the main antenna mast.
AUXILIARY AMPLIFIER
HR Radio
Telephone
KLR
ZF Radio
ANTENNA AMPLIFIER
SWITCHING MODULE
ART-KT5347
45
E46 Driver Information
The second antenna for the FM diversity system is integrated in the convertible top storage cover. The FM2 antenna incorporates a separate amplifier that receives its power
through the antenna lead.
ART-KT-5344
AUXILIARY ANTENNA
AMPLIFIER
ART-ANTEMP
System Operation
Both antennas receive the signals for radio reception. Each signal is amplified by its own
antenna amplifier and the signals are passed two the diversity switching module. The diversity module will lock onto the stronger of the two signals and send it to the radio receiver
for sound system operation.
46
E46 Driver Information
Introduction
Starting September 2000, a family of new generation radios will begin to be phased into
production. The exception to this is the E52 which has been available with the MIR (multiinformation radio) NG radio since series launch in mid 2000.
The NG “New Generation” radios will have increased functions:
•
Radio can be operated without KL R.
•
Radios are world frequency.
•
Car memory programming.
•
Audio mixing on vehicles equipped with navigation.
The radios external appearance has not changed. NG radios can be identified by their “53”
designation.
Overview of the Radios for Each Model
RADIO
TYPE
MANUFACTURER
MODEL
C53
Business with
cassette
Business with indash CD
Business with
MID control and
cassette
Business with
MID control and
in-dash CD
Business MIR
without cassette
Business with
BM control
Philips
E46
INTRODUCTION
DATE
3/01
Alpine
E46
3/01
Phillips
E39/E53
9/00 E39
10/00 E53
Alpine
E39/E53
9/00 E39
10/00 E53
VDO
E52
Start of production
Becker
E46/E39/E53
03/01 E46
02/01 E39
04/01 E53
CD53
C53
CD53
C53
BM53
47
E46 Driver Information
AM
DIVERSITY
FM 1
ANTENNA/
FM 2
FZV RECEIVER FM 3
RF Cable
KL 30
"RAD ON"
signal
CHECK
ENGINE
KL 31
SPEAKER OUTPUT
TO AMPLIFIER
HANDS FREE AUDIO OUTPUT
FROM
UNLOADER
RELAY
BM53
I-BUS
TELEPHONE
WITH INTERFACE
MUTE SIGNAL
SPEAKERS
StarTAC
BMW
MFL
M
IKE
W
B
SRS
AIRBAG
80
60
40
20
3
100
120 140
100
160
180
80
200
60
220
40
½
0
2
120
4
5
1/min
x 1000
6
1
240
20
140
0
7
km/h
MPH
40
ELECTRONIC
MK III NAV.
NAV
AUDIO
POWER
CHECK
ENGINE
GPS NAVIGATION SYSTEM
R
T
A
P
E
G
B
4
2
5
3
6
FM
AM
TONE SELECT
MODE
MENU
13.07.2000 Thursday
10:17
BMBT
KL 58g
LCM III
CD CHANGER
DIGITAL OUTPUT
NG Radio System Overview
Example: E39 with MK III navigation and BMBT
48
E46 Driver Information
10
0
OIL SERVICE
INSPECTION
123456
20
miles
122 4
DIGIT
+72 0F
READOUT
PRND SM
54321
P
!
ABS
K-BUS
GENERAL MODULE
INFO
1
20 15
!
KEY USED
DSP AMP
KL R
Functional Overview
NG Radios
Radio Operation with KL R off
Operation is possible with the key off on the C53 and CD 53 radios. If the radio is turned
on with KL R off, it will play at the last stored volume and settings for 16 minutes until the
General Module sends the sleep command. No changes may be made to the radio unless
KL R is switched back on. The radio can be turned on and off as many times desired.
Diversity Antenna
Antenna diversity has been adapted to the new generation of radios. When the radio is in
operation, the diversity control unit is activated by the “RAD ON” signal.
World Frequency Radio
Radios on vehicles sold in the U.S. are world radios. Specific country settings can be made
using the service mode. The settings are stored in an EEPROM.
Car Memory
If programmed, when locking the vehicle using the remote transmitter the:
• last station
• Volume setting
• Last audio mode (Tape, FM, CD etc.)
are stored according to the key number used. Unlocking the vehicle with the same
transmitter will restore the settings. There is a maximum setting for volume which may be
lower than the setting when the radio was last operated.
Clock
Time can also be displayed when KL R is off by pressing the clock button on the
Radio/MID.
Backlighting
The LCM/LSZ produces two signals for the control of radio backlighting.
• Hardwired KL 58g
• Lights on/off over the K/I Bus.
The radio contains a photo-cell for adjustment of backlighting to ambient conditions.
49
E46 Driver Information
Reset and Voltage Monitoring
A radio reset is triggered by under voltage or the internal processor monitor. The reset
function restarts the radio, similar to turning it off and back on again. Operating voltage is
measured at the KL 30 input. The radio is switched off if the system voltage exceeds 17V
to protect the radio, it will switch on when the voltage falls below 16V.
GAL (Speed Dependent Volume)
The speed signal from the IKE/KOMBI is available to the radio over the K/I Bus. GAL is not
a feature on vehicles equipped with DSP.
Bus Communication
The radio communicates with other modules via the K bus or I Bus dependent on the
model. The information shared over the bus line includes:
• IKE/KOMBI - Terminal status (KL 15, KL R)
• LCM/LSZ - Lights on
• IKE/KOMBI link to TXD - Diagnosis
• MID or BMBT - button or rotary knob status.
• GM - Key used to lock or unlock vehicle
• MFL - audio controls status
NG radios do not use anti-theft codes. Operation of the radio is only possible if
connected to a bus line and the detection of at least one other component.
50
E46 Driver Information
Workshop Hints
Service Mode for NG Radios
A service mode is available as on previous radios as a diagnosis tool and for changing radio
settings. Entering the service mode varies by the device used to control the radio.
To enter the service mode:
C53/CD53 with and without MID:
• Turn on the radio.
• Within 8 seconds, press and hold the “m” button for 8 seconds.
• Scroll through functions using the “+” and “-” keys or the station < > search buttons.
• Turn off the radio to end the service mode.
C53 MIR:
• Turn on the radio.
• Within 8 seconds, press and hold the “SEL” button for at least 8 seconds.
• Scroll through functions using the station < > search buttons.
• Turn off the radio to end the service mode.
BM53 with board monitor:
• Turn on the radio.
• Press and hold the “RDS” button for at least 8 seconds.
• Scroll through the functions using the station < > search buttons.
• Turn off the radio to end the service mode.
BM53 with Widescreen board monitor:
• Turn on the radio.
• Within 8 seconds, press the “INFO” button.
• From the info screen select RDS
• Press and hold the BM control knob for at least 8 seconds.
• Scroll through functions using the station < > search buttons.
• Turn off the radio to end the service mode
51
E46 Driver Information
Service Mode Functions
1. Serial Number: Display of the radio serial number.
2. Software version: Display of the radio software version. Displayed as (calender week,
year, version)
3. GAL: Speed-sensitive volume control. Can be adjusted from level 1-6 using the 6 preset audio buttons. Vehicles equipped with DSP do not use this feature.
4. Field strength and Quality (F/Q): The station currently displayed can be assessed for
field strength and quality. An “F” (i.e. F15) number is used to indicate the strength of the
signal being received by the radio. This is a good test of the antenna system, station signal, and the radio itself. A “Q” (i.e. Q-00) number is used to determine the quality of the
radio station including both the audio and RDS signal if applicable.
5. DSP: This function provides information about whether the vehicle is fitted with DSP.
The value is displayed as a one (fitted) or zero (not fitted) and is communicated by the DSP
amplifier via the I/K bus.
6. TP Volume: Provides adjustment for traffic report minimum volume. Not used in the
US.
7. AF: Alternative Frequency tracking setting. Not used in the US.
8. Area: Used to select the appropriate market setting (USA, Canada, Europe, Japan and
Oceania). Adjust using the pre-set buttons.
9.Index: Display of the revision index.
52
E46 Driver Information
To Remove Radio:
• Remove center dash trim above glove
box by prying off with a trim stick.
• Remove center dash trim over radio by
prying off with a trim stick.
• Remove two screws at the top of radio
assembly.
• Slide radio forward and out of the plastic carrier.
• Remove main radio connector by lifting
connector lock to the upper most position, away from top of radio, using a
screwdriver as show on connector.
• Remove the antenna connection.
• Install in the reverse order.
53
E46 Driver information
E46 MARK II NAVIGATION SYSTEM
COMPONENT OVERVIEW
The E46 Mark II Navigation System is similar to E38/E39 Mark II. All of the E38/E39 Mark
II system components are carried over with the exception of the BMBT:
E46 Specific Board Monitor (BMBT):
•
•
•
•
•
5 inch display (320 X 234 pixel resolution)
Uses on screen soft keys for telephone send/end functions. E38/E39 uses buttons.
Does not include auxiliary ventilation function (not a function of E46 BC/IHKA).
Provides display and control functions for the Audio System (radio, cassette and CD).
Provides display and control functions for systems in the menu display.
TAPE PROGRAM AND
EJECT BUTTONS
MODE = Selection between
Radio, Tape or CD Functions
DOLBY NR
SELECTION
PHOTOCELL SENSOR
(ADJUST BACKLIGHTING)
5 INCH
DISPLAY
RADIO
BROADCAST
DATA SYSTEM
SEARCH
BUTTONS
PROGRAM
RADIO CONTROL KNOB
(INCREMENTAL SENSOR)
RADIO STATUS INDICATOR
(SIGNAL FROM RADIO VIA k BUS)
BMBT CONTROL KNOB
(INCREMENTAL SENSOR)
1 - 6 BUTTONS - Correspond to stored
radio stations and audio CD selections
MENU BUTTON LOCATION - Recalls Main
Menu in Board Monitor Display
1999 MODEL YEAR RADIO CHANGES
•
The 1999 model year radios do not have the weatherband feature.
•
RDS = Radio Broadcast Data System. In the future, this button will put the vehicle
occupants in touch with a wide variety of broadcast data including weather information.
•
PTY = Any unit having RDS will also have a separate button for the PTY feature. It
stands for Program Type and will indicate the type of music being played.
54
E46 Driver Informaytion
The BMBT communicates with interfacing control modules via the K Bus. As with all previous Original Equipment Navigation Systems, the radio electronics are installed in the
trunk. The BMBT sends and receives operation instructions to the radio via bus communication. The Mark II Nav computer continues to provide the RGB output signals to the
BMBT for system function display.
55
E46 Driver Information
E46 BOARD MONITOR & NAVIGATION SERVICE MODE DISPLAYS
The Mark II system provides a service mode display function. These screens provide system hardware/software identification numbers and status of Board Monitor and Navigation
specific functions for use as a diagnostic tool. The screens are accessed as follows:
•
From the Main Menu select “Set”.
•
Once in the Set function, press and hold the menu button for 8 seconds.
•
The next screen to appear is the SERVICE MODE menu.
The first accessible function is “On-board monitor”. Pressing this selection calls up the version screen which provides identification of hardware/ software specific index versions for the
installed system.
Pressing the functions key at the
bottom continues
into
additional
screens including
the Key Functions
and Brightness
controls.
Key Functions tests the key input on the BMBT.
Input status (1-25) will display in the window.
If no keys are
pressed the status will be displayed as “FF”.
Rotating the left
or right rotary
knob displays hex
code input status.
Rotated slowly, the display changes with each increment. The display eventually stops at “1F” in the left
rotated direction and “E0” to the right.
The key function test terminates automatically if no keys
or knobs are moved after a short duration (“00”).
56
E46 Driver Informaytion
The next accessible function is the
NAVI/GRAPHIC
ELEMENT.
This screen identifies hardware/
software specific
index versions for
the installed system.
The Video module selection is not functional since the US version Mark II nav system does not utilize the video module.
The next available
selection
from the service
mode menu is
“GPS”.
This display provides the GPS
receiver module
hardware version
number and
date of programmed software.
Pressing the
functions button
in the lower right
corner of this
screen provides
a sub-selection
menu.
GPS Status provides information
on the exact
coordinates of the vehicle based on the calculations
of the GPS receiver module.
GPS Tracking provides information about the individual satellites currently sending signals to the GPS
57
E46 Driver Information
The next selection available from the SERVICE MODE menu is “Sensor check” which provides:
•
Wheel
speed input
(only one
wheel speed
signal, displayed).
•
Number of
satellites
detected.
•
What mode the GPS receiver module is currently in; (ie: Search)
•
The Gyro status provides the millivoltage value the Nav computer is utilizing for the current vehicle position. This area also includes an icon representing what direction the
vehicle is heading in.
•
The direction status indicates what gear is selected (forward or reverse).
The Sensor check display is intended to be used while test driving the vehicle. Use the legend below to compare with the display status.
STATUS DISPLAY
Wheel Sensors:
WHAT SHOULD BE DISPLAYED
As the vehicle is driven, the
number should increase with an
increase in vehicle speed.
GPS Satellites:
With unobstructed upward view
of sky the display should be > 3
GPS Status:
Gyro:
“See Legend on next page”
Direction icon moves with vehicle
turning movement.
WHAT TO DO IF NOT OK
Check fault codes in
ASC/DSC system. If
necessary carry out wheel
speed sensor test.
Check for interference of
signals to GPS antenna,
Check integrity of circuit
from GPS receiver module
and Nav computer
Replace Navigation
computer.
Milli voltage display value should
be approx 2500 mV (+/- 400mV)
when the vehicle is stationary or
driven straight ahead.
Direction:
58
E46 Driver Informaytion
When the vehicle is turning, the
value must rise or fall which
indicates the gyro sensor is
detecting yaw.
Reverse is displayed when range
selector is in reverse. Forward in
any other range.
Check back up light
signal input.
GPS Status Text Display
1. “GPS fault”
2. “Reception Interference”
3. “No Almanac”
4. “Satellite search”
5. “Satellite contact”
6. “Position known”
Description
Problem with GPS system. Swap GPS receiver module
and or antenna from know good vehicle after checking
GPS status display information described on page 153 .
Problem with GPS system. Same as above.
No Data yet stored from satellites. The GPS almanac is a
memory account of received satellite signals. If the vehicle
battery has been disconnected or after replacing a GPS
receiver module it has an empty memory and requires
satellite signals to become functional. After the receiver
module receives battery voltage and ground, it must be left
outside with an unobstructed sky above with the ignition
switched to KL R for approximatly 15 minutes.
GPS is currently searching for satellite signals.
At least one satellite is found
Vehicle’s Latitude and Longitude known. Navigation is
possible.
The last selection available is the Telematics entry display. This replaces the “VIN” selection
from the E38/E39 Mark II systems. The only requirement of this entry screen is that the VIN
is entered at the VPC when prepped prior to distribution.
This is necessary for the
Emergency program if needed
when calling the
Cross Country
Group Roadside
Assistance
Program.
Additionally, if the vehicle is equipped with a Phase V phone the system will automatically utilize the entered VIN as per E38/E39 Mark II systems.
The VIN is entered at the VPC for all vehicles (with or without a Phase V phone). If the VIN
has been incorrectly entered it can be changed by turning and pressing the rotary knob
when the correct letter or digit of the last seven character of the VIN is displayed.
The balance of the data displayed below the VIN entry is not currently used in the US market.
59
E46 Driver Information
MARK II NAVIGATION SYSTEM CALIBRATION
The calibration procedure of the Mark I system is not required with the Mark II system. This
system self calibrates automatically as the vehicle is driven after following the steps below.
•
System must be fully functional with no faults present in fault memory.
•
Correct Map data base CD installed for your .
•
Vehicle outside with an unobstructed overhead view. Switch ignition on and allow system adequate time to receive a minimum of three GPS signals. This is confirmed by the
green GPS indicator in the map display.
•
Set the map display to the 400’ scale and drive the vehicle on digitized roads. Make frequent turns at intersections where possible.
While driving, the system utilizes the map CD, the received GPS coordinates, the Gyro sensor to determine turn activity and the wheel speed sensor input. It compares all of these
variables and automatically pinpoints the vehicle position.
MARK II NAVIGATION SYSTEM DIAGNOSIS
The Nav computer does not communicate with the DIS/MoDiC.
Diagnosis of the Nav Computer is performed with conventional procedures and by utilizing the Status displays on the previous pages.
Refer to the DIS for RGB output signal oscilloscope displays for visual
confirmation of signal integrity.
The Board monitor (BMBT) does however communicate with the
DIS/MoDiC. Follow the fault symptom path of the DIS Diagnosis
Program for detailed diagnostic procedures.
60
E46 Driver Informaytion
Mk-3 NAVIGATION SYSTEM
Models: E38, E39, E46, E52, E53
Production Date: E46 from 6/00, all others from 9/00
Objectives
After completing this module you should be able to:
•
Recognize the changes to Mk-3 from the previous Mk-2 navigation system.
•
Identify the components used in the system.
•
Review the operating fundamentals of GPS navigation.
•
Describe how to properly code and program the Mk-3 computer.
61
Mk-3 Navigation
Purpose of the System
The Mk-3 navigation system is a factory installed navigation system that replaces the
previous Mk-2 version. The purpose of the system remains the same as previous
navigation systems: To provide the driver with navigation instructions to an entered
destination based on the vehicles current position and the roads available selected from
a digitized road map.
The principle differences of the Mk-3 system over the previous Mk-2 are:
•
GPS receiver is integrated into the MK-3 computer.
•
Optimized memory and faster processor resulting in faster start-up and operation.
•
New split screen and magnifying feature when equipped with wide screen monitor.
(software feature)
•
Same navigation computer used for color board monitor or monochrome MIR display
units.
62
Mk-3 Navigation
System Components
Mk-3 Navigation Computer
The Mk-3 navigation computer is located in
the left side of the vehicles trunk or cargo area.
(In the case of the Z8 it is installed in the storage box behind the passenger seat.)
The navigation computer housing contains:
•
•
•
•
•
•
•
Map CD drive
Hardware for navigation function
GPS receiver
Gyro sensor
Output for audio interface
Output for visual display
Cooling fan for unit
There are two different hardware versions available dependent on the angle of installation
in the vehicle (horizontal or vertical). The Mk-3 is compatible with both board monitor or
MIR display units. (See workshop hints for configuration instructions)
Identification of the Mk-3 computer over the previous versions is easy due to a change in
the face plate design and the elimination of the “CD-IN” LED.
Mk-3 Navigation
Computer
POWER
GPS NAVIGATION SYSTEM
Mk-1 and Mk-2
Navigation Computer
ON
CD-IN
BMW
NAVIGATION SYSTEM
63
Mk-3 navigation
Mk-3 computer
GPS antenna
connection
18 pin ELO
connectors:
X1313: Violet
X1312: Blue
Integrated GPS receiver and Gyro (rotation) sensor
GPS (Global Positioning System) Receiver
The GPS receiver module of the previous Mk-2 system is integrated into the housing of the
Mk-3 computer, further reducing the complexity and the number of components used in
the system. The receiver is not serviceable.
The GPS receiver is responsible for receiving the satellite signals and providing the vehicle’s
position information to the navigation computer.
Information provided by the GPS receiver to the navigation computer can be displayed in
the service mode (see workshop hints) but is not typically used in diagnosis.
Gyro (Rotation) Sensor
The navigation computer contains the electronic (piezo) Gyro sensor that detects rotation
(yaw) of the vehicle as a confirmation that the vehicle is turning. The signal provided by the
gyro is a mili-voltage that changes as the vehicle rotates. The navigation computer uses
the input to track the vehicle along the digitized map and display the exact vehicle position.
The signal is available in the sensor test page of the service mode for diagnosis. The
sensor is not a separately serviceable item and does not require calibration.
64
Mk-3 Navigation
GPS Antenna
The GPS antenna is directly connected to the navigation computer via a coaxial cable.
Locations of the antenna in the vehicles are as follows:
E38:
E39 sedan:
E39 Sport Wagon:
E46 sedan/coupe:
E46 Sport Wagon:
E46 Convertible:
E52:
E53:
Under the rear parcel shelf.
Under the rear parcel shelf.
Behind the dashboard on the left side.
Under the rear parcel shelf.
Above the rear glass under the spoiler.
Behind the instrument cluster.
Left front corner behind the dashboard.
Above the rear glass under the spoiler.
Display Units
Based on the particular model, the factory installed Mk-3 system is displayed using a color
board monitor or on a smaller monochromatic screen (MIR).
E52 MIR (Multi Information Radio)
AM FM
TONE SEL
AUDIO
MENU
NAVIGATION
TELEFON
A-TEMP
MODE
1
2
3
4
5
6
E46/E53 Color Board Monitor
MODE
MENU
DOLBY B-C NR
On-board computer
PTY
TONE
FM
GPS-Navigation
Telephone
RDS
SELECT
AM
Emergency
MENU
Set
09/08/00 Friday
1
2
3
Monitor Off
7:05 PM
4
5
6
BMW MONITOR
E38/E39 Wide Screen Color Board Monitor
(phased in for E53 1/01, E46 9/01)
INFO
MENU
1
4
2
5
On-board computer
GPS-Navigation
3
6
DSP
Aux. Ventilation
FM
AM
MODE
TONE SELECT
Code
Set
11.13.2000 Thursday
Emergency
Monitor off
MENU
10:17
65
Mk-3 navigation
Navigation System Interface
80
60
40
K-BUS
220
40
½
20
0
3
100
120 140
100
160
180
80
200
60
2
120
5
140
DIAGNOSIS BUS
6
1
240
20
4
1/min
x 1000
0
7
km/h
MPH
40
ELECTRONIC
20 15
10
0
!
CHECK
ENGINE
OIL SERVICE
INSPECTION
123456
miles
122 4
+72 0F
20 DIGIT READOUT
PRND SM
54321
P
!
ABS
Telephone
PSE Box
StarTAC
M
W
B
SRS
AIRBAG
BMW
I-BUS
MFL-CM
LCM III
AMPLIFIER
AUDIO SIGNALS
FOR AMPLIFICATION
INFO
BM53
1
4
2
5
3
6
FM
AM
TONE SELECT
MODE
MENU
13.07.2000 Thursday
TAPE PLAYER
AUDIO SIGNALS
CD
PLAYER
AUDIO
SIGNALS
GPS
ANTENNA
10:17
RED SIGNAL
GREEN SIGNAL
NAVIGATION
AUDIO
SIGNALS
BLUE SIGNAL
POWER
GPS NAVIGATION SYSTEM
BO
REVERSE SIGNAL FROM
LCM
Example of E38/E39 with Mk-3 navigation
66
Mk-3 Navigation
DSC
(processed
left front wheel
speed signal)
SC
H
Information/body bus Interface
The navigation computer is integrated into the vehicle bus system as it’s main communication link with the vehicle.
Communication occurs with the following modules:
•
•
•
•
•
•
BMBT - Control inputs
Radio - Display data
GM - Door open
IKE/Kombi - On-board computer data
Telephone PSE Box - Monitor display data, mayday function
DISplus - Coding data
PSE = Portable Support Electronics
Video/Audio Signals
Board Monitor (Top Navigation)
The RGB video signal for all display functions of the board monitor are produced by the
navigation computer graphics stage via three output signals. The Red-Green-Blue signals
are direct inputs to the board monitor. The audio signals for navigation instructions to the
radio are sent via two separate lines.
GPS ANTENNA
VIDEO
RGB
GYRO
GPS
POWER
INFO
MENU
1
4
2
5
On-board computer
DSP
3
6
GPS-Navigation
GPS
-Navigation
Aux. Ventilation
FM
AM
Telephone
Emergency
TONE SELECT
Code
MODE
MENU
Set
Monitor off
11.13.2000
1.13.2000 Thur
hursda
sday
10:1
0:17
GPS NAVIGATION SYSTEM
MIR (Radio Navigation)
Since a color display is not used for the MIR, the navigation information for the display is
sent via a NAV bus. The NAV bus is a single dedicated line between the Mk-3 computer
and the MIR. Audio signals for navigation instructions are sent to the radio via two
separate lines.
AUDIO SIGNALS
AM FM
TONE SEL
AUDIO
MENU
NAVIGATION
TELEFON
A-TEMP
MODE
POWER
GPS NAVIGATION SYSTEM
Mk 3 NAV.
NAV BUS
1
2
3
4
5
6
E52 MIR
67
Mk-3 navigation
Speed Signals
A speed signal is provided to the navigation computer for detection of distance traveled and
vehicle speed to calculate the vehicles position on the digital map. The input is a processed
signal provided by the vehicles DSC control unit.
•
E46: The speed signal used is from the left rear wheel.
•
E38/E39/E52/E53: The speed signal used is from the left front wheel.
Reverse Gear Input
The reverse gear input is used by the navigation computer to distinguish between the
vehicle backing up or turning around.
•
E38/E39/E52/E53: The reverse input is a high signal produced by the LCM III.
Mk-3 NAV
LCM
Reverse
lights
• E46: The reverse input is a high signal supplied by a splice from the back-up lights.
Automatic Transmission
version shown
KL15
KL30
Reversing
Light Relay
K6325
Mk-3 NAV
Reverse
lights
GS 20
68
Mk-3 Navigation
Principle of Operation
The Global Positioning System is a satellite based system developed by the US Department
of Defense that provides both military and civilian users accurate information about
location.
The GPS system uses 24 satellites in six
orbits 12,550 miles above the Earth moving at 1.7mi per second. Usually 7 to 10
satellites are in view over any one point on
the earth.
The GPS satellites are basically extremely
accurate clocks that broadcast a coded
signal representing time. The GPS receiver
determines it’s distance from the satellite
by measuring the time it takes between
satellite transmission of the signal and
reception to the receiver. The receiver
does this with at least 2 other satellites and
uses the information to determine the vehicles latitude, longitude, and altitude. The
accuracy of the system for civilian use is
within 100m (300ft).
The vehicle must have an unobstructed view of the sky to receive the maximum amount of
satellite signals. Trees, large buildings and excessive cloud cover can block the reception
of the satellites’ transmissions.
69
Mk-3 Navigation
The GPS antenna passes the signal to the GPS receiver incorporated in the navigation
computer. A CD with map data is loaded in the CD drive of the navigation computer. The
navigation computer combines the vehicle position calculated by the GPS with this map
data.
The current position of the vehicle can be shown on the on-board monitor by selecting
“Emergency” from the main menu.
The driver can enter a destination. The navigation computer calculates a route from the
current location to this destination based on selectable criteria (main use of highways,
shortest distance, etc.). The calculated route is shown in the route display.
The navigation computer generates the RGB color video signal for all on-board monitor
displays. These three signals are sent over separate shielded wires to the on-board monitor.
In the case of the E52 MIR (also referred as radio navigation) which does not have a color
display, the visual display data is sent via one wire called the navigation bus. On both systems, color and monochrome display, the audio output from the navigation computer for
voice directions is sent over two separate wires.
The driver has the choice of displays that utilize a color map with an icon of the vehicle
being traced on the map or the use of arrow indicators and distance data shown on the
on-board monitor display. Vehicles equipped with the wide screen board monitor have a
split screen option that includes both display methods. The MIR only makes use of the
arrows and distance display. With the assistance of voice prompts, the navigation
computer indicates how and where to get into the correct lane or turn off.
The navigation computer calculates the distance traveled from the wheel speed signal
delivered by the DSC control unit.
The gyro incorporated into the navigation computer housing informs the navigation computer when the vehicle is turning. An alternative route is re-calculated automatically if the
driver does not follow the original route instructions.
Once the driver has reached their destination, the navigation computer is ready for
another destination input.
Refer to the on-board monitor owners manual for instructions on using the navigation system
software.
70
Mk-3 Navigation
Workshop Hints
Replacing the Mk-3 navigation computer
When replacing the Mk-3 navigation computer be aware that there are two hardware
variants depending on the installation position (vertical or horizontal).
The ignition should be in position 0 during removal and replacement of the computer. After
installing, close all doors, hood and trunk. A bus line reset will be carried out within two
minutes. Resetting allows the gyro to perform a calibration run. Do not move the car
during this reset period.
The coding sequence for the Mk-3 navigation computer has been changed from the
previous Mk-2. There is now an additional step (configuration) that must be done before
the software can be loaded.
After resetting, a configuration signal is needed to allow the computer to load the correct
software for use with a board monitor or MIR. This is performed using the DIS coding program (CD 22.0 onward) and the Navigation System operating software (CD V15.0 onward).
Note: Vehicles using the wide screen BM require CD V16.1 onward.
Print
1. From the DIS/MoDiC Coding /Programming
select “1 ZCS Coding”
Change
End
Services
BMW Coding/programming: E46 SERIES
1 Recoding
2 Retrofit
3 Display coding
code and code
for printout
4 Conversion
4
Conversion
5 Service
measures
2. Select the appropriate series
(E46,E39,E38,E52,E53)
3. Select “4 Conversion”
4. Select “3 IKE?Kombi”
Note
5. Select “2 language”
6. At the prompt “is the CD ROM present?”
select yes , but do not install the operating
software CD ROM yet.
7. First select the main language and then an
additional language. (i.e. English-spanish)
8. Select the gender of the navigation audio
voice.
9. Select “automatic coding-yes”
Print
Change
End
Services
BMW Coding/programming: E46 SERIES
Have "BMW Navigation" CD-ROM ready.
Do not insert it in
the CD drive yet!
KOMBI
Start
automtic coding?
Yes
No
Note
71
Mk-3 navigation
10. After coding is done the DIS/MoDiC
instructs you to follow the instructions on
the monitor for the installation of the
Navigation System CD ROM.
11. Place the navigation system software in the
navigation computer CD drive.
Important: Do not switch the ignition off during the
software loading procedure. Do not use any software for the Mk-3 earlier than CD V15.0.
12. Once loading has been completed, remove the
CD and then confirm completion by pressing
the rotary push-button on the monitor.
13. Turn off the key for 10 seconds, then turn it
back on and conduct a functional check.
14. After this step has been finished, encode the
navigation computer using the “Recoding” path
in ZCS Coding. The coding process involves
coding vehicle specific data: VIN, Model,
Telematics data etc.
INFO
1
4
2
5
3
6
FM
AM
Software Update
Programming
Application Software Version 2.0
Language 1: Amerikan
Language 2: Spanish
Progress
MODE
The software status can be confirmed from the
“Set” screen for Mk-3 systems.
•
3 = Third generation system Mk-3.
•
1 = Device variant (1=Color screen, 2= MIR
MENU
SW 3-1/20
monochrome screen).
• 20 = Software version of the graphic
component (Version 2.0).
TONE SELECT
ursday
USA
km
1/100km
C
24h
E
miles
mpg
F
12h
dd.mm
on
mm/dd
off
km/l
set
set
ME
10:17
After the navigation computer has been successfully programmed and coded the vehicle
should be left in an area with a clear view of the sky with the key in KL R for at least 15 minutes to complete the calibration process.
72
Mk-3 Navigation
Service Mode
Just as Mk-2, Mk-3 provides an on-screen service mode for diagnosis. The service mode
provides five different test screens:
•
•
•
•
•
On-board monitor
Navigation/Graphic element
GPS
Sensor Check
Telematics
To
•
•
•
•
•
enter the Navigation Service Mode:
Turn the ignition key to position 1 (KL R).
From the Menu screen select “SET”.
Once in the Set screen, press and hold the “MENU” button for 8 seconds.
The Service Mode menu will appear on the display.
Select from the Service Mode menu for navigation specific tests.
INFO
INFO
1
4
2
5
3
6
FM
AM
MODE
SET
Language
Distance
Consumpt.
Temp.
Clock
SW 3-1/20
USA
km
1/100km
C
24h
dd.mm
Date
on
Audio+OBC
11.13.2000 Thursday
E
miles
mpg
F
12h
km/l
TONE SELECT
set
mm/dd
off
set
MENU
10:17
1
4
2
5
3
6
FM
AM
MODE
SERVICE MODE
On-board monitor
NAVIGATION/GRAPHIC ELEMENT
TONE SELECT
Video Module
GPS
Sensor check
Telematics
MENU
11.13.2000 Thursday
Press and hold for 8 seconds after entering
the “Set” mode
10:17
Service Mode main menu display
Diagnosis
Diagnosis is carried out using Test Modules in the Diagnosis Program as well as on-screen
in the Service mode.The Sensor Check display is intended to be used while test driving the
vehicle. The following pages contain charts with explanations of the Service Mode display.
SENSOR CHECK
return
11.13.2000 Thursday
DIS
BMW
BMW DIS
0
00
Satellite search
02485
Forward
10:17
BMW DIS
Wheel sensor:
GPS satellites:
GPS status:
Gyro:
Direction:
73
Mk-3 navigation
STATUS DISPLAY
Wheel Sensors:
WHAT SHOULD BE DISPLAYED
As the vehicle is driven, the
number should increase with an
increase in vehicle speed.
GPS Satellites:
With unobstructed upward view
of sky the display should be > 3
GPS Status:
Gyro:
“See Legend below”
Direction icon moves with vehicle
turning movement.
WHAT TO DO IF NOT OK
Check fault codes in DSC
system. If necessary carry
out wheel speed sensor
test.
Check for interference of
signals to GPS antenna,
Check integrity of circuit
from GPS antenna to nav
computer.
Replace Navigation
computer.
Milli voltage display value should
be approx 2500 mV (+/- 400mV)
when the vehicle is stationary or
driven straight ahead.
Direction:
When the vehicle is turning, the
signal voltage should increase on
right hand turns and decrease on
left hand turns.
Reverse is displayed when range
selector is in reverse. Forward in
any other range.
GPS Status Text Display
1. “GPS fault”
2. “Reception Interference”
3. “No Almanac”
4. “Satellite search”
5. “Satellite contact”
6. “Position known”
74
Mk-3 Navigation
Check back up light
signal input.
Description
Problem with GPS system. Swap nav computer and or
antenna from know good vehicle after checking GPS
status display information
Problem with GPS system. Same as above.
No Data yet stored from satellites. The GPS almanac is a
memory account of received satellite signals. If the vehicle
battery has been disconnected or after replacing a nav
computer it has an empty memory and requires satellite
signals to become functional. After the nav computer
receives battery voltage and ground, it must be left outside
with an unobstructed sky above with the ignition switched
to KL R for approximatly 15 minutes.
GPS is currently searching for satellite signals.
At least one satellite is found
Vehicle’s Latitude and Longitude known. Navigation is
possible.
Menu
GPS/Status
Display
G-speed
Heading
Rec status
Pos-src
PDOP
HDOP
VDOP
Explanation
Relative speed over the ground
Direction of travel
Search/track/position receiver status
Number of satellites available for analysis
Accuracy of the calculated location
<8=sufficient determinations of location
<4=very good determinations of location
GPS/Tracking
info
CH
PRN
S/N
Visible Sat
Channel
Satellite detection
Better reception as the value increases
Number of visible satellites, receivable
Signals, depending on time of
day/configuration
Satellite database, loaded automatically after
15 minutes
VIN (Automatically assigned during coding)
Color code or text
Telephone network/contract number
Customer specific info
On/off status
Telematics services on/off status
Logging off telematics services
Almanac
Telematics
PDOP
HDOP
VDOP
S/N
Gyro
Dir
VIN
Color
GSM
BMW info
Emergency call out
Initialization
Logging off
Position Dilution of Precision
Horizontal Dilution of Precision
Vertical Dilution of Precision
Signal/noise relationship
Piezo gyro sensor (in navigation computer)
Direction of travel
75
Mk-3 navigation
PARK DISTANCE CONTROL
INTRODUCTION
Park Distance Control is a safety/convenience system that is an option on the E46. The system is carried over from the E39 and features the ultra-sonic sensors on the rear bumper
only.
The sensors detect the close proximity to other objects when maneuvering the vehicle in
tight spaces (such as parallel parking or parking in narrow garages spaces).
The driver is warned, through an audible tone
(beeping), when the vehicle comes close to another object. As the distance to the object decreases, the beeping frequency increases until a steady
tone is produced. As the distance to the object
increases, the steady tone will return to a beep
and stop when the vehicle moves away from the
object.
The PDC is automatically switched ON when the
ignition is switched on, however it does not
become active until the vehicle is shifted into
reverse.
76
E46 Driver Information
PDC COMPONENTS
The PDC consists of the following components:
PDC CONTROL MODULE - Mounted in the trunk on the right side above the battery.
The PDC control module activates the ultrasonic sensors mounted in the rear bumper
cover. After activation, the module monitors the signals coming back through the sensors.
Through this signal, the control module is able to determine the distance to any object close
to the bumpers of the vehicle. As the vehicle comes close to an object, the control module
will activate the acoustic warning through the right rear audio system speaker.
FOUR ULTRASONIC SENSORS - Mounted in the rear bumper. The sensors are small transmitter/receiver modules that are specifically designed for automotive use. The sensors are
limited to the following angles of monitoring:
• 90° on the horizontal plane
• 60° on the vertical plane
77
E46 Driver information
TRANSMITTING MODE
The control module sends a 40 Khz signal to the sensor and each sensor is then activated
in a specific sequence (firing order). The ceramic element of the sensor vibrates and produces an ultrasonic sound wave that is sent out from the bumper.
RECEIVING MODE
If the sound wave contacts an object, the wave is bounced back to the sensor. The returning wave causes the ceramic element to vibrate creating an electrical signal as feedback to
the control module.
The control module determines the distance to the object by the time difference between
the sent signal and the received ultrasonic wave signals.
78
E46 Driver Information
SYSTEM OPERATION
When KL 15 is switched ON, the PDC system is switched "ON", in the standby mode. The
system performs a self-check of the ultrasonic sensors and control electronics.
When the vehicle is shifted into reverse, the system is activated and the sensors are activated in the predetermined order.
If an object is detected within the operating range of one the sensors, a signal is sent to the
PDC control module and the acoustic warning is generated. At the same time the control
module checks the signals from the adjacent sensors to help determine the actual distance
to the object.
As the distance to the object decreases, to approximately 1 ½ feet, the output acoustic frequency increases until a steady tone is generated.
As the distance to the object increases the frequency will decrease until the object is out of
the monitoring range of the sensor.
79
E46 Driver information
80
E46 Driver Information
Review Questions
1. What is the principle Bus line used on the E46? List the modules that are located
on this bus.
2. Describe how the Instrument Cluster receives the speed signal from the ASC/DSC
control unit.
3. What information does the cluster use to determine the Service Interval? Where can
the Coded Consumption Limit be found?
4. Discuss how the Instrument Cluster and the LSZ share data storage. What would
happen if a cluster from another vehicle is installed? Why does this happen?
5. If the LSZ module were to fail, what lights would remain functional?
6. Explain the possible testing/troubleshooting procedures for an E46 equipped with
Xenon lights.
7. Which module is responsible for the automatic head light adjustments? What type of
sensors are used in this system and where are they located?
8. Where is the Diversity Antenna Amplifier located on an E46 Touring?
9. Describe how to enter the Radio service mode on a vehicle with a Board Monitor.
81
E46 Driver information
10. List the most significant changes made to the Mk-3 navigation computer over the
previous Mk-2.
12. How can the signal provided by the gyro sensor to the navigation computer be
checked?
13. What step is necessary before loading the navigation computer operating software CD
on a newly replaced Mk-3 navigation computer? Where can the software status be
confirmed after it has been loaded?
14. How is PDC switched on? What diagnosis is possible on the system?
82
E46 Driver information
Table of Contents
E46 CENTRAL BODY ELECTRONICS
Subject
Page
ZKE V Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Power Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Windshield Wiping/Washing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Sport Wagon Rear Wiper/Wash System. . . . . . . . . . . . . . . . . . . . . . . . . . . 9
AIC (Rain Sensor). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Central Locking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
E46 Convertible Central Locking. . . . . . . . . . . . . . . . . . . . . . . . . . . . ..18
E46 Sport Wagon Central Locking. . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Remote RF Key less Entry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Model Year 2000 Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Power Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
Convertible. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
Interior Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Anti-Theft (DWA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Power Seat Control and Memory Function . . . . . . . . . . . . . . . . . . . . . . . 54
E46 Convertible Front Seats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Passenger Seat Memory. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Mirror Memory System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Seat Heating (up to 9/99). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
SZM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Lumbar Support. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .75
Dual Power/Heated Outside Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
Consumer Cutoff . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
Initial Print Date: 7/98
Revision Date: 11/22/00
E46 CENTRAL BODY ELECTRONICS
Model: E46 (all models)
Production: From 6/98
Objectives
After completing this module you should be able to:
•
Explain what functions are controlled by the GM V.
•
Describe the operation of the windshield wipers and the interaction with AIC.
•
Understand the different methods of locking and unlocking the vehicle.
•
Identify the internal components of the model year 2000 key and describe it’s operation.
•
Describe the window anti-trap circuit used on various E46 models.
•
Explain the operation of DWA.
•
Describe the purpose and operation of the UIS sensor.
•
Understand how seat and mirror memory systems operate.
•
Explain the construction of the E46 Convertible seat and the SGS system.
2
E46 Central Body Electronics
ZKE V INTRODUCTION
ZKE V is the Central Body Electronics system installed in the E46. Many of it’s features
and functions are similar to previous BMW ZKE systems with minor changes, added
features, and refinements.
The following functions are directly controlled by the General Module V (GM V):
•
•
•
•
Windshield wiping/washing
Central locking with power trunk/tailgate
release
FZV Key less Entry
Power window control
•
•
•
•
Car Memory/Key Memory Capabilities
Interior lighting
DWA alarm system (optional)
Consumer cut-off/sleep mode
The following functions are included as body electrical systems but are not directly
controlled by the GM V:
• AIC (Rain Sensor) if equipped.
• Sunroof operation (Sunroof Control module on K Bus).
• Driver’s seat electrical adjustment with memory (Seat Memory control module on K Bus)
• Passenger seat electrical adjustment
• Comfort Entry Aid (Convertible only)
• Seat Heating
• Side Mirrors - Memory/adjustment/heating
ZKE V includes the following features:
•
Similar to the E36 GM IV, the E46 GM V controls it’s respective peripheral components
directly (no P Bus). It does however communicate with other pertinent control modules
via the K-bus.
•
The Central Locking system uses a door lock actuator with hall effect sensors.
•
The GM V is responsible for the Key Memory feature. It provides the added
convenience of identifying users of the vehicle. Whenever the vehicle is locked or
unlocked via the FZV key less entry system, a unique key identification signal (key
number) is transmitted to the General Module.
The key identification signal alerts the GM V to communicate with other control systems
over the K Bus to store (when locked) or reset (when unlocked) certain driver adjustable
settings for the driver using the specific key. The GM also resets certain driver
adjustable settings that it controls directly.
3
E46 Central Body Electronics
The E46 Body Electronics system control modules are:
•
General Module V: main controller for ZKE functions. The GM V communicates with
other vehicle control modules via the K bus.
•
Seat Memory Module - SM: Located in the driver’s seat base, the SM controls and
memorizes the driver’s seat position(s). The SM communicates with the GM V via the
K bus.
•
Sunroof Module - SHD: Located above the rear view mirror, the sunroof module
controls it’s integral sunroof motor as on previous systems. The SHD communicates
with the GM V via the K bus.
4
E46 Central Body Electronics
POWER DISTRIBUTION
The maintenance free battery is connected to the power distribution system by the Battery
Safety Terminal (BST). The BST is activated by the MRS system in the event of a severe
impact preventing the main B+ cable to the starter and generator from shorting to ground.
Trunk Mounted
200 Amp Fuse
BATTERY SAFETY TERMINAL (BST)
250
A single 250 amp main
harness fuse (F108)
located in the trunk
protects the power
distribution circuit to
the fuse panel in the
glove box.
CIRCUIT
TO FUSE
BOX
STARTER/GENERATOR
CIRCUIT
BATTERY
SAFETY
TERMINAL
5
E46 Central Body Electronics
GLOVE BOX MOUNTED FUSE PANEL
The power distribution center of the E46 is
located in the glove box. The fuse panel is
accessed by rotating two twist locks 90O
allowing it to drop into view as shown.
The fuse panel includes fuses 1 - 71.
The two large red 50 amp fuses (F36, F37)
provide power protection for the IHKA blower
Fuse Locations
(F101-F107)
Located above the fuse panel are
additional high amperage power
distribution fuses (F101-F107).
This location replaces the front
passenger seat (under carpet) and
trunk location of the E38/E39 vehicles.
Fuel Pump Relay
Horn Relay
Fog Light Relay
The electronics carrier is located forward of
the glove box. It contains the following
components as noted in the photograph.
IHKA Blower
Relay
6
E46 Central Body Electronics
General Module V (GM V)
WINDSHIELD WIPING/WASHING
•
All wiping/washing functions are
controlled by the GM.
•
The E46 Windshield Wiping System may
be optionally equipped with a Rain
Sensor. This added function detects rain
drops on the windshield and
automatically activates the wipers in the
intermittent mode if the stalk switch is in
the intermittent position.
•
Output control of the wiper motor is WINDSHIELD WIPER
DOUBLE RELAY
through a double contact relay. The relay
is located in the engine compartment E-box and is tan in color.
•
The system has four wiping stages and four interval wiping speeds. The wiping stage
inputs are coded signals through a two wire link with a combination of high/low inputs
as on previous systems. The wiping stages include:
SINGLE: Holding the wiper switch down in the single position provides a ground signal to
activate the slow speed circuit providing wiper operation until the switch is released.
INTERMITTENT: The intermittent wiping time inputs are provided by a potentiometer
mounted in the wiper stalk switch.
• The intermittent
wiping intervals are
dependent on the
road speed.
• As road speed
increases, the
wiping interval
delay is decreased.
SLOW (I) AND FAST (II): The stage I and stage II wiping speeds are also affected by road
speed. The factory encoded settings are the same as previous systems:
•
Stage I automatically switches to intermittent when the vehicle is stopped
•
Stage II switches to stage I when stopped.
Note: This feature is known as “Switch Back when Stationary” and may be de-activated or activated in CKM.
7
E46 Central Body Electronics
WINDSHIELD WASHING: Pulling the Windshield Wiper Switch rearward closes the
“windshield wash” contacts and provides a switched ground input to the GM. The GM
activates the windshield washer pump directly via a power output final stage transistor.
8
E46 Central Body Electronics
SPORT WAGON REAR WIPER/WASH SYSTEM
The rear wiper/washer is a function of the ZKE system. The rear wiper motor and gear
assembly is mounted in the tail gate through insulating bushing to prevent operation noises from being transmitted into the body’s interior.
The wiper pivot bearing, wiper shaft and wiper arm are mounted on the rear window. A
mechanical coupling is used to connect the two components as on the E39 wagon.
9
E46 Central Body Electronics
SPORT WAGON REAR WIPER/WASH SYSTEM
Operation
Operation of the rear wiper/washer is controlled from the wiper stalk switch on the steering
column. The scope of operation is as follows:
•
•
•
•
INTERMITTENT WIPE - Standard operation
PROGRAMMED INTERMITTENT WIPE
CONTINUOUS WIPE
WASHING CYCLE
Pressing the wiper stalk switch forward to the first detent activates the rear wiper in the
intermittent mode. The timed interval is approximately 7 seconds. The full sweep and park
positions of the wiper arm are recognized by two hall sensors on the motor gear assembly.
If the wiper is switched OFF, the wiper arm will return to the park position.
Programming Procedure - for the wiping interval is as follows:
•
•
•
•
Briefly switch the wiper ON/Off.
Wait the desired interval time.
Switch the wiper back ON again
The OFF time will be the programmed interval - up to approximately 30 seconds.
Continuous wiping - is activated any time the transmission is shifted into reverse. The rear
wiping module receives the reverse signal for continuous wiping activation.
Rear window washing - is activated by pressing the stalk switch forward past the wiping
detent. The washer cycle is as follows:
• Wash cycle 1 - washer pump is switched ON for 1.5 seconds. The wiper activation starts
1 second later.
• Wash cycle 2 - washer pump is switched ON for .5 seconds - after a delay of of .8 seconds. Wiper continues to operate.
• Wash cycle 3 - washer pump is switched ON for .5 seconds - after a delay of .8 seconds.
This is followed by two wipe dry cycles.
NOTE: The wiper will remain in the intermittent wiping mode after washing until wiper is
switched off.
10
E46 Central Body Electronics
SPORT WAGON REAR WIPER/WASHER I P O
BACK-UP LIGHTS
RELAY OR SWITCH
11
E46 Central Body Electronics
AIC (RAIN SENSOR)
The Windshield Wiping System will also be available with an optionally equipped Rain
Sensor. The Rain Sensor provides added driver convenience and enhances safety by
automatically activating the intermittent function of the windshield wipers when water
droplets are detected on the windshield.
COMPONENTS:
The rain sensor unit is mounted on the top center area of the interior windshield surface
directly behind the rear view mirror. The unit contains:
•
Optical Prism Body: This portion of the unit is
permanently fixed to the windshield. It can not be
removed and can only be replaced with a
replacement windshield.
The prism body has a reflective surface that faces
the back of the windshield. The prism body also
acts as the windshield mount for the Rain Sensor
Control Module.
•
Rain Sensor Control Module: The control module incorporates the following;
-
Infra Red Emitter and Detector Diodes
Optics heater (prevents condensation from forming on the diodes and prism)
Optics evaluation and control electronics
The control module requires four signals for operation; KL R, KL 31, Windshield Wiper
Motor Park Signal Feedback and K Bus interface.
12
E46 Central Body Electronics
THEORY OF OPERATION:
The optical infra red portion of the sensor operates by the principle of refraction (bending
of a light ray). The rain sensor control module activates the emitter diode which sends a
beam of infra red light through the windshield on an angle. The set angle is important
because it provides the beam with a calculated reflective path back to the detector diode.
The beam is reflected back into the windshield due to the density difference of the glass
compared with the ambient air on the outside surface of the glass. When the windshield is
clean (no rain drops, moisture or dirt) the detector diode receives 100% of the infra red light
that the was sent by the emitter. With this condition, the rain sensor evaluation electronics
determines the windshield is free of rain drops.
The density of water is closer to that of glass than air. When rain starts to accumulate in
the sensor monitoring area, it causes part of the infra red beam to extend past the outside
surface of the glass and into the rain drop. When this occurs, the beam is refracted and
only part of the beam returns to the detector diode.
The rain sensor evaluation
electronics
determines
the
windshield has a few rain drops
(or dirt) on it.
The intensity of the returned infra red beam diminishes proportionally with an increase of
water droplets. The rain sensor control module generates a signal proportionate to the
amount of rain on the windshield and broadcasts it to the GM V via the K bus.
The GM V activates the intermittent wipe cycle if the windshield wiper stalk switch is in the
intermittent position. It also adjusts the frequency of wiping the windshield depending on
the four position thumb wheel.
13
E46 Central Body Electronics
RAIN SENSOR FUNCTION:
The rain sensor is online as soon as it receives KL R operating power.
•
When the windshield wiper stalk switch is placed in the intermittent position the GM
signals the rain sensor control module via the K Bus of the request for intermittent
wiping and the position of the knurled wheel (sensitivity).
•
As an acknowledgement, the rain sensor sends a command via the K Bus to activate
the wiper motor. If more than 12 seconds pass before the GM receives the
acknowledgement, the GM concludes the rain sensor has a defect and operates the
intermittent wipe function as a system not equipped with a rain sensor. The wiper
intermittent cycling is based solely on the knurled wheel setting.
•
The rain sensor continuously monitors the windshield for rain accumulation and signals
the GM to activate the wipers based on the knurled wheel position and how fast the rain
accumulates on the windshield.
•
The knurled wheel position signal (1-4) via the K bus informs the rain sensor of the
selected level of sensitivity.
-
Position 1 (least sensitive) delays the wiper activation signal.
Position 4 (most sensitive) sends the wiper activation signal to the GM sooner.
•
When the wiper motor park contacts signal the GM of the wiper arm position, the signal
is simultaneously sent to the rain sensor as an indication that the windshield has been
cleared of water drops and causes the rain sensor to reset the sensitivity delay timer
back to 0.
•
Depending on the intensity of the rain the wipers will be operated continuously as if set
in the normal wiper stalk switch position regardless of the knurled wheel setting. For
this reason, the vehicle speed signal on the K bus is not utilized on rain sensor equipped
wiper systems.
•
If the ignition switch is turned off with the wiper switch in the intermittent position, the
rain sensor will only become active after the ignition is switched back on and one of the
following occurs:
-
The stalk switch is moved from the intermittent position and then back.
The knurled wheel setting is adjusted.
The wash function is activated.
The reason behind this switching strategy, is to have the driver make a conscious
decision to activate the system.
14
E46 Central Body Electronics
RAIN SENSOR CONTROL MODULE ADAPTATION
The rain sensor control module adapts to the optics system environment as follows:
Windshield Aging: As the vehicle ages the possibility of stone chipping in the rain sensors
monitoring area may occur which will cause a loss of light in the optics system.
The control module adapts for loss of light based on the intensity of the detected infra red
light with a cleared windshield (wiper motor park signal). Therefore, the rain sensors
function is not adversely affected due to windshield aging.
Dirty Windows: The rain sensor adaptation reacts less sensitively to a dirty windshield (dirt,
road salt, wax residue) after a completed wipe cycle. A dirty windshield has a film on it that
diminishes the ability of the infra red to refract into present water droplets. This causes a
delay in the rain sensor detection capabilities which lengthens the time intervals on an
intermittent wipe.
SERVICE NOTE FOR VEHICLES EQUIPPED WITH THE RAIN SENSOR:
Make sure the wiper blades are in perfect condition. Only use window cleaner to clean the
windows. Dirty windows can cause the Rain Sensor control module to set a fault
due to the end limits of its adaptation abilities.
WINDSHIELD WIPER SYSTEM FAILSAFE OPERATION
The GM provides failsafe operation of the wiper system if faults are detected with any of the
following input signals:
FUNCTION
FAULTED INPUT DETECTED
FAILSAFE FUNCTION
Intermittent wipe
Short or open circuit of
the knurled wheel signal
Delay value for setting 3
used.
Intermittent wipe
with Rain Sensor
Faulted Rain Sensor or K Bus
Signal corrupt
Normal intermittent wipe
implemented
Wiper motor not
functional moving
Park contact feedback signal
takes longer than 16 seconds
Wiper motor control
deactivated for 3 minutes
WINDSHIELD WIPER SYSTEM DIAGNOSIS
The GM monitors the circuits of the wiper potentiometer, wiper motor, double relay, the
windshield washer pump and terminal 30. The DIS or MoDiC provide fault symptom
troubleshooting following the new E46 Diagnostic concept as well as Status and
component activation functions.
15
E46 Central Body Electronics
CENTRAL LOCKING
SYSTEM FEATURES:
• The Central Locking system of ZKE V controls the door lock, trunk lock and Fuel Filler
Flap actuators.
•
The familiar single/double locking strategy is maintained from
previous systems with the introduction of a new style door
lock mechanism combined with dual actuator motors.
The new style actuators are sealed, self contained units with no
replaceable parts. The door lock actuators use hall effect
sensors in place of pin contacts and microswitches to provide:
•
•
Door lock key position (driver’s door only),
Door open/closed status (replaces door jamb switch).
The mechanical interior lock rods only lock the actuator they
control. There is no affect on the central lock control of other
doors. The rear doors are equipped with the child lock out lever
preventing the door from being opened from the inside
regardless of the actuators position.
•
The automatic locking feature activates the door lock
actuators when a road speed signal of 5 MPH is detected via the K-Bus. The factory
default encoding of this feature is off, but can be encoded on for individual users with
the Key Memory function.
•
The Driver’s door lock location is the only point outside of the vehicle where the key can
mechanically control all of the central locking system functions. The outside locks
(driver’s door and trunk) incorporate the familiar overrunning lock cylinder that breaks
away and freewheels if an attempt is made to destroy the lock with a screwdriver, dent
puller, etc.
•
The trunk can be locked/unlocked with the key but does not lock/unlock the entire
vehicle as on previous systems. When unlocked, the trunk can be opened by
depressing the trunk release switch pad located above the license plate or from the
remote trunk button in the left kick panel as on previous systems. Pressing the trunk
release button on an FZV key also opens the trunk.
•
GM V and EWS 3.3 interface via the K bus to monitor double lock status and to initiate
double lock override. This feature allows the doors to be opened from the inside if an
accepted EWS key is switched on in the ignition when double locked. 2000M.Y
vehicles allow a double locked vehicle to be opened using the central locking switch
inside of the vehicle.
16
E46 Central Body Electronics
Continuous locking/unlocking will initiate a timed arrest of the locking system. The GM counts
each time the locks are actuated. After approximately 12 cycles, the timed arrest is active.
The timed arrest is deactivated one actuator cycle for every 8 seconds until the counter is
reset to 0. The timed arrest is overridden if a crash signal is received from the MRS II.
•
The Selective Unlocking feature is used by the GM V. A single unlock request from the
driver’s door with the key or via the remote transmitter unlocks the driver’s door only. A
second unlock request unlocks the remaining doors and trunk. This feature can be
modified for individual users in Key Memory to activate all lock actuators simultaneously.
K-bus
KI.30
•
KI.30
The central locking switch is housed in a combined housing with the hazard flasher
switch. Locking the vehicle from the central switch single locks the vehicle except for
the fuel filler flap.
KI.R
•
Driver's Door
Lock Actuator
Hallsensor
ER/KO
ERFT
Hallsensor
ZS/KS
VRFT
Hallsensor
TK
TKFT
TKBH
MZS
MZS
MER
MER
M
Passenger Door
Lock Actuator
MVRFT
M
Hallsensor
M
30MVR
Left Rear Door Lock
M
Right Rear Door Lock
TKBH
TKFH
Hallsensor
GM V
MZS
M
M
Hallsensor
MZS
MER
MER
MVR
MVR
M
M
TOEHKI
CS (AIRBAG)
Interior
Trunk
Release
Button
Fuel Filler Flap Actuator
MER
M
MZS
KI.58g
31L
TZV
TOEHK
HKK
MERHK
VRHK
Central lock
GM
Trunk light circuit
DWA
Cancel
Switch
Valet
Position
Switch
Trunk Lock
Trunk Lock
Actuator
M
LSZ
KZL
Trunk Lid
Unlock
Switch
17
E46 Central Body Electronics
E46 Convertible Central Locking
The glove box is integrated into the scope of the central locking system on the E46iC. An
additional actuator is positioned above the glove box to lock it whenever the central locking system is activated. Additionally, the trunk is locked out whenever the top storage cover
is unlocked while the top is being raised or lowered. The top storage cover motor hall sensor signals the GM any time the cover is unlocked.
The CVM receives a signal from the GM over the K-Bus, whenever the trunk is opened,
which locks out the soft top operation.
A micro switch on the glove box lock cylinder signals the GM to lock the trunk electrically
for the valet key position. The trunk can only be opened mechanically with either FZV key
or the wallet key.
All other functions of the central locking system remain the same as the E46 Sedan and
Coupe.
The antenna for the FZV system is incorporated with the receiver into the interior rear view
mirror.
18
E46 Central Body Electronics
E46 Sport Wagon Central Locking
Tailgate and Window Locking System
The tailgate can be opened from any of three input signals including:
• Remotely from FZV
• Interior tailgate release button - on left kick panel
• Unlock switch pad - located above the license plate
Any of these input request signal the GM to activate the tailgate latch motor. The GM will
also switch on the interior lights with a unlock request for the tailgate.
The window is opened from the release switch located on the rear wiper arm cover.
Pressing the switch signals the GM to activate the rear window release relay.
19
E46 Central Body Electronics
DRIVERS DOOR LOCK ACTUATOR
The driver’s door lock provides
the following familiar signals to
the General Module:
•
•
•
Lock / Unlock,
DWA arm/disarm
Convenience closing and
opening signals.
• UNLOCK
• DWA DISARMED
NEUTRAL
• CONVENIENCE
OPENING (hold
until activated).
It also provides a mechanical link
to manually lock/unlock the
actuator in the event of a failure.
• DOUBLE LOCK
• DWA ARMED
• CONVENIENCE
CLOSING (hold
until activated).
MANUAL
LOCK
MANUAL
UNLOCK
The GM monitors these key positions over two wires. The signals are generated by two
hall effect sensors (Hall Sensor 1 & 2) located in the actuator.
When the key is turned, a plastic cylinder in the lock actuator is simultaneously rotated by
the lock tumbler extension rod. An asymmetrical shaped magnet is incorporated in the
plastic cylinder, which when rotated changes the magnetic influence on the hall sensors.
The presence of a magnet in close proximity to the sensing surface of either hall sensor
creates a coded input over the two wires that the GM uses to determine the key position.
•
•
Magnet in front of sensor, current flow through the sensor is <5 mA (0).
Magnet rotated away from sensor, current flow through the sensor is >12 mA (1).
Hall effect sensors improve the actuators reliability since they are impervious to moisture
and there are no wear contacts.
•
Key in the neutral position, both
sensors are simultaneously
influenced by the magnet - 0/0.
•
Key turned to the unlock position
from neutral, hall sensor #1
magnet segment moves away
from hall sensor - 1/0.
•
Key turned to lock position from
neutral, hall sensor #2 magnet
segment moves away form hall
sensor - 0/1.
20
E46 Central Body Electronics
TUMBLER
EXTENSION ROD
HALL SENSOR 1
HALL
SENSOR 2
PLASTIC CYLINDER
WITH ASYMMETRICAL MAGNET
(Shown in the Lock Position)
There are two motors incorporated in each actuator that provide two separate functions:
•
Single lock/unlock function. Also known as central lock, this motor controls the
mechanical lock mechanism when the central lock button is pressed to single lock the
vehicle. The lock mechanism is fully locked at this point but can still be opened from
the interior by pulling the appropriate interior door handle twice or by pressing the
central lock button again. When single lock function is activated, the fuel filler flap
actuator is not locked.
•
Double lock/unlock function. Also known as central arrest, this motor is activated
only when the vehicle is locked from the outside at the driver’s door lock with a key or
when the GM receives a lock request from the FZV system. In this case the double
lock motor is activated simultaneously with the single lock motor. The function of the
double lock motor is to mechanically offset an internal rod disabling it from unlocking
the vehicle from the interior. This prevents the doors from being unlocked by any means
except from an unlock request at the driver’s door or via the FZV remote key.
PLASTIC
CYLINDER
WHEN IN DOUBLE LOCK AN INTERIOR
ACTUATED UNLOCK ROD IS OFFSET
PREVENTING THE LOCK MECHANISM FROM
BEING MECHANICALLY UNLOCKED
HALL EFFECT SENSORS
1&2
SINGLE
LOCK
DOUBLE
LOCK
MOTOR
ACTUATOR IN UNLOCKED POSITION
ACTUATOR IN LOCKED POSITION
21
E46 Central Body Electronics
DOOR CONTACT HALL SENSOR
Also included in the drivers door actuator is a third hall effect sensor. This sensor signals
the door open/closed status to the GM. This sensor replaces the door jamb mechanical
switch of previous systems. The rotary latch plate position activates the door contact hall
sensor.
•
When the door latch is closed, current flow through the sensor is <5 mA (0).
•
When the door is open, current flow through the sensor is >12 mA (1).
The passenger side front door and both rear door lock actuators only include this hall effect
sensor (hall sensor 3). Hall sensors 1 & 2 are not required.
22
E46 Central Body Electronics
LOCK ACTUATOR CONTROL
All door lock actuators and the fuel filler flap actuator are controlled directly by the GM via
four internal load relays. The drivers door lock actuator has a separate circuit for the
selective unlocking feature. If this feature is disabled by key memory encoding, the driver’s
door lock actuator selective unlock circuit is activated simultaneously with the balance of
the motors during unlock.
DOUBLE LOCK CONTROL
-SWITCHED POWER-
LEFT
REAR
DOOR
RIGHT
REAR
DOOR
PASS.
DOOR
DRIVER’S
DOOR
LEFT
REAR
DOOR
RIGHT
REAR
DOOR
PASS.
DOOR
DRIVER’S
DOOR
LEFT
REAR
DOOR
RIGHT
REAR
DOOR
PASS.
DOOR
DRIVER’S
DOOR
FUEL
FILLER
FLAP
GROUND
SINGLE LOCK CONTROL
- SWITCHED POWER SELECTIVE SINGLE LOCK
CONTROL DURING DOUBLE LOCK:
NOT ACTIVE
FUEL
FILLER
FLAP
GROUND
SINGLE LOCK CONTROL
- SWITCHED POWER SELECTIVE SINGLE LOCK
CONTROL DURING SINGLE LOCK:
DOUBLE LOCK CONTROL
-GROUND-
UNLOCK CONTROL
- SWITCHED POWER -
FUEL
FILLER
FLAP
SINGLE UNLOCK CONTROL
- SWITCHED GROUND SELECTIVE SINGLE UNLOCK
23
E46 Central Body Electronics
TRUNK LID SWITCH CONTACTS
The trunk lid position (open/closed) and trunk lock key positions are input signals to the GM V.
The trunk lid closed/open signals come from the trunk lid switch contact located in the
trunk lock actuator motor assembly.
When closed, the trunk contact provides a
ground signal to the GM signifying a "closed
trunk". This contact also serves as the trunk
light switch when the trunk lock is open.
ACTUATOR MOTOR
TRUNK LID SWITCH CONTACT
The actuator motor only runs in one direction
to release the latch mechanism. The latch
mechanism can also be manually unlocked
with the key.
Located on the trunk lock are two
additional microswitches for key
position status signalling to the
General Module.
LATCH
MECHANICAL UNLOCK
ROD FROM KEY
TRUNK LATCH
ACTUATOR WITH
TRUNK LID
CONTACT SWITCH
VIEW OF TRUNK LID
LOOKING UP FROM FLOOR
LEFT
RIGHT
•
MECHANICAL
UNLOCK ROD
FROM KEY
TRUNK
LOCK
1. DWA CANCEL ACTIVATE SWITCH
2. VALET KEY POSITION SWITCH
•
Valet position
switch: With the
key lock in the valet
position, this switch
provides a ground
signal to the GM.
The GM locks out
the interior trunk
release button
preventing the trunk
from being opened.
DWA Cancel Switch: When the trunk is opened with the key, this switch provides a
ground signal to the GM preventing the DWA from activating if armed.
24
E46 Central Body Electronics
CENTRAL LOCKING BUTTON
The central lock button in the center console
provides a momentary ground input signal to the
GM. This input initiates a single lock for each
door and the trunk. The fuel filler flap remains
unlocked for refueling purposes.
If a door is manually opened while centrally
locked, the remaining doors stay locked.
The opened door can be re-locked when closed
by manually locking or pushing the central button
twice. This allows the locks of the remaining
doors to be re-synchronized again.
On M.Y. 2000 vehicles, a vehicle that is Double Locked may be opened from inside by
pressing the central button once and then manually opening the door from the inside.
TRUNK REMOTE UNLOCK (328i & 330i)
The trunk can be opened from inside the vehicle by
pressing the remote trunk button when the vehicle is
unlocked or single locked from the central lock button.
The remote trunk button is locked out when the trunk is
locked in the hotel setting and when the GM detects a
vehicle speed signal > 4 MPH via the K-bus.
The switch provides the GM with a momentary ground
signal when pressed.
CRASH SIGNALLING
The Multiple Restraint System control module provides a switched signal to the GM in the
event of an accident. The signal is an output function of the MRS control module and
becomes active when MRS determines a crash has occurred.
When active, the GM unlocks the door lock actuators, switches on the interior lights and
signals the LSZ via the K bus to activate the hazard warning flashers.
Once the crash signal is active, the GM will not respond to lock requests from the system
until the ignition switch is cycled or a front door is opened.
25
E46 Central Body Electronics
REMOTE RF (KEY LESS) ENTRY
•
The remote key receiver is part of the antenna amplifier and is installed in the left “C”
pillar.
The receiver produces a digital
signal based on the transmitter
command and sends it to the GM
for processing.
The GM then carries out all remote
lock system, window and sunroof
opening features, along with DWA
arming/disarming functions.
•
The frequency at which the key
transmits the radio signal to the
antenna amplifier is 315 MHz.
•
The system is also used to convey the key identification number being used to
lock/unlock the vehicle. This is a requirement of the Key Memory feature.
26
E46 Central Body Electronics
Features of the key less entry system include:
•
Locking/unlocking of doors, trunk,
fuel filler lid.
•
Selective unlocking of driver’s door
(as with key in lock)
•
Arming/dis-arming of DWA alarm
system (if equipped).
•
Remote unlocking of the trunk only.
•
Comfort opening of windows and
sunroof
•
Interior lighting activation (search
mode).
•
Panic mode alarm activation (if
equipped).
•
Automatic correction for up to 1000
erroneous activation signals.
•
Low transmitter battery fault code
storage in the GM.
•
3 volt lithium battery (commercially
available CR 2016) is used as the
power supply for the key
transmitters.
•
An EEPROM is used to store the key
data. The data is no longer lost when
the battery is replaced and
initialization is not required.
•
The key incorporates an LED that signals the
operator of signal transmitting, key initialization
status and key self test indication.
•
The keys are now delivered with a four color label
sheet containing four different colored labels for
each of the four possible FZV keys.
Radio Transmitter Key up
to 1999 M.Y.
This is a helpful addition to differentiate the FZV
keys during initialization preventing the possibility
of mis-assigning the key ID which would change
the encoded Key Memory functions.
27
E46 Central Body Electronics
REMOTE KEY INITIALIZATION
The initialization of the FZV keys is required to establish the Lock/Unlock signal
synchronization with the GM V. The initialization procedure provides the GM with a key
identification number and a “rolling code” for each key. If the initialization is not performed,
the GM will not respond to the key signals.
Up to 4 remote keys can be initialized. They must
be initialized at the same time. Key initialization is
only possible with the vehicle unlocked.
Procedure:
1. Close all doors and have all keys available.
2. Using key number 1, turn the ignition switch to
KL R, then switch off within 5 seconds and
remove the first key.
3. Within 30 seconds of turning the ignition
switch to “off” Press and hold button #2.
4. While holding button #2, press and release
(“tap”) button #1 three times within 10
seconds.
5. Release both buttons. The LED in the key will
flash momentarily. The GM will immediately
lock and unlock the doors signaling a
successful initialization.
6. If additional keys need to be initialized repeat steps 3 - 5 within 30 seconds.
7. Switching the ignition to KL R completes the initialization.
SERVICE NOTE: The key memory function of the GM responds to the key identification
number of each key. If the keys are not initialized in the same order prior to initialization,
the key memory functions activated by the keys will not be assigned correctly.
Always initialize the keys in the same order.
28
E46 Central Body Electronics
LED STATUS
The following functions can be checked with the LED:
•
Flashing LED when pressing a button. Indicates that the data is being transmitted.
(battery voltage between 3.2 - 2.6 volts)
•
No LED activity when pressing a button:
1. ZKE responds to pressed button only to unlock a locked vehicle. Indicates the battery
is between 2.6 - 2.2 volts. Replace battery.
2. No unlock of vehicle. Indicates battery is below 2.2 volts. Replace battery.
FZV KEY TEST
Pressing the trunk release and lock buttons together activates the key test. If the battery and
FZV key EEPROM are “OK”, the LED will come ON for approximately 1 second.
29
E46 Central Body Electronics
MODEL YEAR 2000 FZV KEY
Visual Changes:
•
•
•
•
•
•
New appearance with blue and white BMW roundel.
New button arrangement (larger buttons) with sequential operation (enhanced operating
convenience)
Rechargeable battery replaces replaceable batteries. Charged by EWS ring antenna.
The key housing is encapsulated and can not be opened.
The LED has been omitted.
Key will be used in E46, E38 and E39 vehicles.
Features of the keyless entry system include:
•
Up to 4 radio-control keys can be operated in conjunction with one vehicle.
•
Locking/unlocking of doors, tailgate,
fuel filler lid.
•
Selective unlocking of driver’s door (as
with key in lock)
•
Arming/dis-arming of DWA alarm system
(if equipped).
•
Remote unlocking of the tailgate only.
•
Comfort opening of windows and
sunroof
•
Interior lighting activation (search mode).
•
Panic mode alarm activation..
•
Automatic correction for up to 1000
erroneous activation signals.
•
Low transmitter battery fault code
storage in the GM.
•
An EEPROM is used to store the key
data.
•
Keys delivered with a four color label
sheet containing four different colored
labels for each of the four possible FZV
keys.
ZKE - 24
30
E46 Central Body Electronics
TAILGATE OPENS
REMOTE KEY INITIALIZATION
The initialization of the FZV keys is required to establish the Lock/Unlock signal
synchronization with the GM. The initialization procedure provides the GM with a key
identification number and a “rolling code” for each key. If the initialization is not performed,
the GM will not respond to the key signals.
Up to 4 remote keys can be initialized. They must be initialized at the same time. Key
initialization is only possible with the vehicle unlocked.
Procedure:
1. Close all doors and have all keys available.
2. Using key number 1, turn the ignition switch
to KL R, then switch off within 5 seconds and
remove the first key.
3. Within 30 seconds of turning the ignition
switch to “off” Press and hold the arrow
button.
4. While holding the arrow button, press and
release (“tap”) the roundel button three
times within 10 seconds.
5. Release both buttons.
The GM will
immediately lock and unlock the doors
signaling a successful initialization.
6. If additional keys need to be initialized repeat
steps 3 - 5 within 30 seconds.
7. Switching the ignition to KL R completes the initialization.
SERVICE NOTE: The key memory function of the GM responds to the key identification
number of each key. If the keys are not initialized in the same order prior to initialization, the
key memory function activated by the keys will not be assigned correctly.
Always initialize the keys in the same order.
ZKE
31 - 25
E46 Central Body Electronics
FZV KEY RECHARGEABLE BATTERY
From KL R, the battery inside the key head is charged inductively by the EWS ring antenna
via a coil antenna integrated in the key. The charging process is controlled by electronic
circuitry integrated in the key.
•
The service life of a radio-control key used under normal conditions corresponds to the
vehicle lifespan.
•
If the FZV keys are not used (ie: stored in a drawer), the battery will be discharged after
approx. 1.5 years.
•
The time required to fully charge a discharged battery is approx. 30 hours.
•
The remote control can be operated about 15 times after a charging period of approx.
30 minutes (driving time).
The key data is stored in a transponder chip. The transponder chip is a wireless read and
write EEPROM. It is powered via the ring coil at the steering lock. Power is applied
electromagnetically when the key is in the ignition switch from KL R.
The power supply is used both for data transfer as well as for charging the battery. This has
been made possible by new development of the transponder chip.
As with previous systems, every press of an FZV key also provides the battery charge
condition. When the FZV electronics receives a low power condition message three
successive times, the GM sets a fault indicating a low battery within a specific key. The
LCM is also informed via the bus system and alerts the driver via an instrument cluster
matrix message.
If the battery is recharged (used operate car), the fault will be automatically deleted when
five successive messages are received indicating a charged battery condition.
The battery has no affect on the EWS III communication function!
ZKE - 26
32
E46 Central Body Electronics
ZKE - 27
33
E46 Central Body Electronics
POWER WINDOWS ( Sedan, Coupe and Sport Wagon)
Features of the Power Window system:
• Control of the front and rear door window motors is carried out directly by the GM.
• One-touch operation in both directions on all windows.
• Cable type window regulator used for all windows.
• Anti-trap detection is provided by the pressure sensitive finger guard (same as E38/E39).
• A new style window switch was introduced with the E46. The switch is pulled up to raise
the windows and pushed down to lower them.
• The rear window switches located in the rear doors can be deactivated by the pressing
child lock out switch in the center console.
• Convenience closing/opening of the windows from the driver's lock cylinder or
convenience opening only from the FZV remote key (FZV operation can be owner
customized with the Car Memory Function).
• Window operation with the ignition switched off until a door is opened or 16 minutes has
elapsed after the key is switched off.
• Window load switching is through relays integral of the GM. The GM V monitors the
current draw for end limit position. The maximum run time for the window motors is
limited to 8 seconds. This allows the motors to be switched off if the end limit load
sensing fails.
34
E46 Central Body Electronics
GM V
35
E46 Central Body Electronics
POWER WINDOWS (Convertible)
Power window operation for the Convertible is slightly with the addition of the central power
window switch located in the console between the window switches on the left side. The
central switch allows all four windows to be opened with one touch operation or closed if
the switch is held.
The rest of the window switches allow one touch operation for opening. The driver’s window switch is the only one touch close switch due to the elimination of the anti-trap protection feature.
The power windows are also opened when the top is lowered for approximately 1.5 seconds to ensure clearance when the top is lowered into the storage compartment. If the top
switch is held after opening, the windows will close again.
36
E46 Central Body Electronics
COMPONENTS
NEW STYLE WINDOW SWITCHES
The E46 power window switch design is a new push - pull type switch. Each switch
provides the GM V with the familiar coded ground signaling strategy as previous two wire
switches.
Pushing a switch to the first detent and holding provides a single ground signal on one wire
requesting the GM to operate the window motor in the down direction. When released, the
ground signal is removed and the window motor stops.
Momentarily pushing the switch to the second detent and releasing provides an additional
ground signal on the second wire requesting the “one touch mode”, operating the window
motor automatically. The motor runs the window down until it reaches it's end stop.
The switch functions in the same manner for the upward run of the window motor but the
ground signal sequencing is reversed.
Four door vehicles have a single window switch located in the door handle trim.
REAR WINDOW CHILD LOCKOUT SWITCH
The rear window child lockout switch is incorporated in the driver's side window switch
block. It provides a constant ground signal to the GM preventing the windows from being
operated from the rear door switches.
The lockout switch ground signal is overridden by the GM if the MRS crash signal is
activated.
37
E46 Central Body Electronics
SERVICE NOTE:
Switch block removal from the console
has changed on the E46.
The console trim must be removed
from the console base. The switch
blocks can be removed by pushing the
lock tabs and dropping the switch
from the trim.
POWER WINDOW MOTORS
The window motors are mounted on the
cable regulators (E38/E39). The window
motor control circuit consists of two wires for
operating the motor in both directions.
The motors are activated by relays in the GM.
The relays provide either power or ground
depending on the direction of window travel.
The GM controls the polarity of the motor
based on a request to run the window
(window switch, Convenience Opening/
Closing).
The windows are run to their limit stops which is detected by an amperage increase in the
control circuit. Additionally, the window run cycle is limited to an 8 second duration if in
case the amperage increase is not detected or there is a malfunction with the regulator.
WINDOW MOTOR LIMIT STOP FUNCTION
If the windows are run up and down continuously a limit stop function is activated to
prevent the window motors from overheating. The GM monitors the number of times the
window motors are activated. It counts each cycle and stores the number in memory.
If the repetitive window activation (up/down) exceeds one minute, the GM deactivates the
internal relays and disregards any further input requests. The GM provides motor activation
after a short duration but not for the full one minute monitoring cycle.
Over time, the GM slowly reverses the stored count of activation until the stored number
equals 0.
38
E46 Central Body Electronics
WINDOW ANTI-TRAP DETECTION( Sedan, Coupe and Sport Wagon)
The window anti-trap detection feature is only active in the one touch and convenience
close modes of operation. If the window switch is pushed/pulled and held, the Anti-trap
feature will not function.
The rubber pressure guards are located at the
top edge of each door frame for the Sedan and
Sport Wagon and are incorporated into the felt
edge protector in the Coupe. Each guard
consists of two contact strips that close when
subjected to pressure. This provides anti-trap
detection and signal generation to the GM V.
When the contact strip closes, the window
immediately (10ms) reverses direction as with
previous anti-trap systems. The contact strip
does not require that the anti-trap feature be
initialized prior to operation.
The E46 pressure sensor finger guard has a
resistance of 3.0 KOhm and it is monitored for
open circuit. When pressed, the monitored
resistance changes to <1KOhm. Faults with the anti-trap system require that the window
switch be held to close the window.
CONVENIENCE OPENING/CLOSING
As with previous ZKE systems, the GM V provides the convenience open/close feature
providing control of the power windows (and sunroof) from outside the vehicle with the key
in the driver’s door lock. The FZV provides the same function for the opening only.
•
The anti-trap feature is active during convenience closing from the driver’s door lock.
•
The convenience open feature provides outside activation of the windows and sunroof
in the same manner.
•
If the GM receives a request to operate convenience close or open for more than 110
seconds, the function is deactivated and a fault code is stored.
•
The Car Memory Feature can activate and deactivate the Convenience Open Feature
from the FZV’s control.
39
E46 Central Body Electronics
SUNROOF
The E46 optional sunroof is mechanically similar to previous systems. All of the electronic
controls and relays are contained in the sunroof module (SHD). The module is connected
to the K-Bus for comfort closing/opening, unloader signalling during engine startup,
diagnosis and fault memory purposes
K BUS
SUNROOF SWITCH
Mounted in the sunroof motor trim cover is the sunroof switch. Also similar to previous
systems, the switch provides coded ground signals for system operation.
The following switch signals are generated over three wires through coded combinations:
•
•
•
•
•
•
Rest position
Slide open request (press and hold switch - first
detent of open position)
Automatic slide open request (press further to
second detent and release)
Tilt open (press and hold)
Slide close request (press and hold switch - first
detent of close direction)
Automatic slide close request (press further to
second detent and release)
40
E46 Central Body Electronics
SUNROOF MOTOR/MODULE (SHD)
The combined motor module has a 13 pin
connector for interfacing the switch, and
vehicle harness (power ground and K bus.)
The motor contains two hall effect sensors
that monitor the motor shaft rotation
providing sunroof panel position.
The hall sensors also provide the end limit cut
out function for the SHD once the system is
initialized. The SHD counts the pulses and
cuts the motor out prior to the detected end
run of the sunroof panel.
INITIALIZATION
Initialization is required for the SHD to learn the end positions of the motor's travel. The hall
sensors provide pulses for motor rotation, the SHD counts the pulses and determines
where the panel is by memorizing the stored pulses.
If the system is not initialized, the sunroof will only operate in the tilt up and slide close
positions. Initialize as follows:
•
Press and hold the sunroof switch in either the tilt up or slide close positions for 15
seconds.
•
The sunroof motor operates momentarily signifying initialization acceptance.
The SHD memorizes the pulses from the hall sensors on the next activation of the motor
by driving the panel to its end run positions. The SHD senses an amperage increase and
determines the end run position. The counted number of pulses is then used as the basis
for calculating the panel position.
ANTI TRAP FEATURE
The anti-trap feature of the sunroof uses a hall sensor to detect obstructions while the
sunroof is closing (pulse frequency slowed down) in the automatic close function. The antitrap feature is shut down prior to full closing (4mm from full closed) to allow the sunroof to
seat into the seal.
Additionally, the anti-trap feature is not functional when the switch is held in the manual
close position.
41
E46 Central Body Electronics
SHD SELF DIAGNOSIS
The SHD monitors its operation and stores fault codes if a defect is determined: The SHD
monitors the following conditions:
•
SHD motor relays: The relays are checked for sticking contacts (plausibility) and non
functional contacts.
•
Hall effect position sensors: The SHD must detect a pulse frequency from the hall
effect sensor(s) during operation.
•
Sunroof Switch: The SHD monitors the signal plausibility of the coded signaling from
the sunroof switch.
SUNROOF FAULT RESPONSE CHARACTERISTICS
If a fault occurs with any of these functions, the SHD responds as follows:
•
•
•
Overrides the end run detection.
Switches the motor off if the relay contacts stick for more than 500 ms.
Switches the motor off if pulses are not received.
EMERGENCY OPERATION OF SUNROOF
If the sunroof motor does not respond to the switch signals, the hex key in the trunk lid tool
kit is used to manually turn the motor shaft drive as on previous systems
42
E46 Central Body Electronics
INTERIOR LIGHTING
The GM controls the interior lighting automatically with the status change of several
monitored inputs. The lighting can also be manually controlled using the interior light switch.
FT lock
Hallsensor
KI.30
TK
BT lock
TKFT
TKBT
GM V
FH lock
Hallsensor
TK
TK
Hallsensor
BH lock
TKFH
TKBH
TK
Hallsensor
IB
CS
SIB
VA
VB 31
Footwell
light
VB 31
Interior/
reading light unit
Interior/
reading light
Interior/
reading light
VB 58g
IL
IL
IL
VB 31
LL
LL
VB 31
LL
VB 31
LL
COMPONENTS
DOOR CONTACTS
As mentioned in the Central Locking Section, the new style door lock actuators contain a
hall effect sensor for the purpose of monitoring door open/closed status (hall sensor 3 in
the driver's door actuator). The hall effect sensor is located directly behind the rotary latch
plate encased in the actuator. The sensor is activated by the rotary latch plate's position.
•
Door closed, the rotary latch plate is in the latched position. Current flow through the
hall sensor is < 5 mA.
•
Door open, the rotary latch plate is in the open position. Current flow through the hall
sensor is > 12 mA.
A change in current flow informs the General module when a door is opened or closed.
43
E46 Central Body Electronics
INTERIOR LIGHT UNIT ASSEMBLIES
Front seat interior/map light unit:
The overhead front seat interior light
unit contains a single main interior
light. The light is controlled by the
GM automatically or by momentarily
pressing interior light switch located
on the light assembly.
The switch provides a momentary
ground signal that the GM
recognizes as a request to either
turn the light on (if off) or turn the
light off (if on).
If the switch is held for more than 3 seconds, the GM interprets the continuous ground
signal as a request to turn the interior light circuit off for the Workshop Mode as on previous
systems. The workshop mode is stored in memory and will not come back on even if the
GM is removed from it's power supply and reconnected. The switch must be pressed to
turn the lights back on.
There are two reading/map lights also located in the assembly. Each map light is
mechanically controlled by depressing it's corresponding on/off switch. The power supply
for the map lights is supplied by the GM through the Consumer Cut Off circuit.
Rear seat interior/reading light units:
In each C pillar trim panel is an interior/reading light unit. These units each contain an
interior light that is controlled with the front interior light and a mechanically switched
reading light on the consumer cut off circuit.
Front footwell lights:
In each front footwell, there is also a courtesy light. These lights are only operated when
the GM provides power to the interior lighting circuit.
44
E46 Central Body Electronics
AUTOMATIC CONTROL FUNCTION
The GM provides 12 volts (linear application providing soft on feature) to the interior lighting
circuit when the one of the following input signal statuses change:
•
Door contact hall sensor active (door opened)
•
An Unlock request from the driver's door key lock hall sensors are received. This only
occurs if the ignition switch is off.
•
An Unlock request is from the FZV keyless entry system is received via the K bus. This
only occurs if the ignition switch is off as well.
•
The ignition switch is switched off and the vehicle exterior lights (LSZ) have been on for
a minimum of 2 minutes prior. This information is provided to the GM via the K bus.
•
Active crash signal from the MRS control module.
•
Lock button of FZV key is pressed with the vehicle is already locked (interior search
function).
The GM gradually reduces the full 12 volt power supply (linear reduction providing soft off)
until the lights are off when the following input signal statuses change:
•
•
Immediately after the ignition switch is turned to KL R with the driver's door hall sensor
door contact closed.
When the vehicle is locked (single or double) with the door contacts closed.
•
When the vehicle door contacts are closed. The lights remain on for 20 seconds and
then go to soft off.
•
After the interior search function is activated, the lights will automatically turn off (soft off)
after 8 seconds.
•
After 16 minutes with a door contact active (open door) and the key off, the lights are
switched off (consumer cutoff function).
•
The component activation function of the DIS also has the ability to switch the lights.
The Interior lighting output circuit of the GM is approximately 3.5 amps with all lights on.
<#>
45
E46 Central Body Electronics
ANTI-THEFT (DWA) SYSTEM
(BMW Center installed accessory)
All E46 vehicles are factory prepared (prewired and GM programmed) to provide the DWA
function. The DWA system components are available as a retailer installed optional
accessory. Once the DWA system components are installed the GM must be encode to
recognize the installed components and carry out DWA functions. This is done with the
ZCS “Retrofit” program function using the DIS or MoDiC.
The GM utilizes existing components and/or circuits as part of the DWA system:
•
•
•
•
•
Door lock hall effect sensor contacts (door open/closed).
Trunk lid switch contact (monitored for closed trunk).
Trunk lock key position switch (located on the trunk lock, this switch signal prevents
DWA from activating if armed when the trunk is opened with the key).
Hood switch (monitored for closed hood, located under the hood).
DWA status LED (part of rear view mirror).
The DWA optional accessory kit includes the following:
•
•
•
Tilt sensor (pre wiring in area of installation in right trunk area).
UIS Interior compartment monitoring sensor (pre wiring in area of installation in center
headliner).
DWA siren (pre wiring in area of installation right cowl area next to IHKA housing).
Hood switch
KI.R
MHK
Driver's Door
Actuator (FT)
Hallsensor
KI.30
Passenger Door
Actuator (BT)
TK
TKFT
TKBT
TK
Hallsensor
Left Rear Door Actuator (FH)
GM V
Hallsensor
TK
Right Rear Door Actuator (BH)
TKFH
TKBH
TK
Hallsensor
DWA - LED
DWAL
NG
INRS
GRL
HKK
Tilt sensor
SIRENE
ERHK
GM
STDWA
Valet
Switch
UIS sensor
Siren
DWA
Cancel
Switch
M
Lock
46
E46 Central Body Electronics
Trunk
actuator
COMPONENTS
DOOR CONTACTS
As mentioned in the Central Locking Section, the door lock contact hall effect sensors
provide status of door open/closed.
•
When the door latch is closed, current flow through the sensor is <5 mA (0).
•
When the door is open, current flow through the sensor is >12 mA (1).
The GM will activate the siren if a door open signal becomes active when the DWA is
armed.
TRUNK LID SWITCH CONTACTS
The trunk switch contact is located in the trunk lock actuator assembly. When closed, the
trunk contact provides a ground signal to the GM signifying a "closed trunk". The GM will
activate the siren if the trunk switch contact ground signal opens when the DWA is armed.
TRUNK LOCK KEY POSITION SWITCH
Mounted on the trunk lock cylinder are two switches:
•
Valet position switch: With the
key lock in the valet position, this
switch provides a ground signal to
the GM. The GM locks out the
interior trunk release button
preventing the trunk from being
opened.
•
Trunk opened with key switch:
When the trunk is opened
mechanically with the key, this
switch provides a ground signal to
the GM preventing the DWA from
activating if armed.
47
E46 Central Body Electronics
HOOD CONTACT SWITCH
HOOD SWITCH
Located on the right side engine
compartment, the hood contact switch
provides a ground signal to the GM
signifying an open hood.
The plunger of this switch can be pulled
up past a detent causing the switch
contact to open. This feature can be
used to simulate a closed hood with the
hood open when diagnosing the DWA
system.
DWA LED
As on previous systems, the DWA indicator is located in the rear view mirror. The LED is
equipped in all E46 vehicles and is not part of the retailer installed accessory DWA system.
The LED is provided with constant battery voltage (KL 30). The GM provides a switched
ground signal providing the various blinking signals used to convey DWA status to the
vehicle operator (covered further on).
48
E46 Central Body Electronics
TILT SENSOR
Located in the right trunk area
above the battery, the tilt sensor is
an electronic sensing device with
the sole purpose of monitoring
the vehicle's parked angle when
DWA is armed.
The sensor requires three signal wires to perform its function:
•
KL 30 - Constant battery voltage
•
Signal "STDWA"; switched ground input signal provided by the GM indicating DWA
armed/disarmed status. The tilt sensor is used as a splice location for the STDWA
signal to the Siren and UIS interior protection sensor.
•
Signal "NG"; switched ground output signal provided to the GM. The signal is used for
two purposes,
1. As a momentary acknowledgment that the tilt sensor received STDWA and is
currently monitoring the vehicle angle.
2. If the tilt sensor detects a change in the vehicle's angle when DWA is armed, signal
NG is switched to inform the GM to activate the siren.
When the tilt sensor receives the STDWA signal from the GM it memorizes the vehicle's
parked angle. The angle of the vehicle is monitored by the solid state electronics. Once
armed, if the angle changes, the tilt sensor provides a switched ground signal to the GM to
activate DWA.
49
E46 Central Body Electronics
INTERIOR PROTECTION (UIS)
The E46 uses an interior protection sensor known as UIS. Similar to the FIS previously
equipped on the E38/E39, the UIS monitors the vehicle interior for motion through
ultrasonic sound waves. The UIS is a combined transmitter and receiver.
The interior sensor is mounted in the center of the headliner panel even with the "B" pillar.
Due to the design of the vehicles interior, the sensor is uni-directional and must be installed
in the proper direction to ensure proper operation of the system (trim cover ensures
directional installation).
Every time the DWA system is armed (signal
STDWA), the sensor adapts to what ever
objects might be stationary in the interior.
The sensor emits ultra sonic waves in a
programmed timed cycle. It receives echos
of the emitted waves.
The UIS amplifies the received sound wave signals and compares them with the
transmitted waves. The UIS also checks the incoming echos for background hiss (wind
noise through a partially open window) and adapts for this.
• If the echos are consistently similar, no movement is detected,
• If the echos are altered, (inconsistent), the UIS determines motion in the interior
compartment.
If motion is detected, the UIS changes to a constant cycle and the echo is compared again.
If the inconsistency is still present the UIS sends the activate siren signal (INRS) to the GM.
As with the tilt sensor, the UIS is also switched OFF when the vehicle is locked two times
within ten seconds. This allows the sensor to be switched OFF for transportation purposes.
50
E46 Central Body Electronics
ALARM SIREN
The siren from the DWA accessory kit is
installed in the vehicle cowl on the
passenger side of the vehicle. This
location provides a secure position with
loud acoustic output.
The siren contains electronic circuitry
for producing the warning tone when
the alarm is triggered. The siren also
contains a rechargeable battery that is
used to power the siren when the alarm
is triggered.
SIREN INSTALLATION
The rechargeable battery will allow the siren to sound if it or the
vehicle’s battery is dis-connected. The siren battery is recharged,
from the vehicle’s battery when DWA is not in the armed state.
The siren has four wires connecting it to the system; KL 30, KL 31,
Signal STDWA (arm/disarm signal from GM), and Signal SIRENE
(activate siren output signal to the GM)
The arm/disarm output signal from the GM (STDWA) is provided to the Tilt sensor, UIS
sensor and the siren simultaneously. The arm/disarm signal is a switched ground that
signals the components of DWA armed/disarmed status.
The activate siren signal (SIRENE) is high whether DWA is armed or disarmed. If a
monitored input activates the alarm, the high signal to the siren is switched to a 50% duty
cycle at the GM. The control circuitry in the siren activates the siren driver. If the DWA is
armed and the battery is disconnected the siren recognizes the normally high “SIRENE”
signal as suddenly going low, the siren is also activated.
KL 30 UIS SENSOR
SIRENE
KL 30
INRS
ACTIVATE
KL 30
NG
STDWA
ACTIVATE
ARM / DISARM SIGNAL
GM V
DWA SIREN
TILT SENSOR
51
E46 Central Body Electronics
DWA ARMING/DISARMING
•
The DWA is armed every time the vehicle is locked from the outside with the door lock
cylinder or FZV key.
•
The LED in the rear view mirror flashes as an acknowledgment along with the exterior
lights and a momentary chirp from the siren.
•
The GM monitors all required input signals for closed status (door closed, trunk closed,
etc.) The inputs must be in a closed status for a minimum of 3 seconds for the GM to
include them as an activation component. If after 3 seconds any input signal not in the
closed status is excluded (this is acknowledged by the DWA LED) preventing false alarm
activation's.
•
If the DWA is armed a second time within 10 seconds, the tilt sensor and interior
protection sensor are also excluded as alarm activation components. This function is
useful if the vehicle is transported on a train or flat bed truck to prevent false alarm
activation's.
•
While armed the trunk can be opened with out the alarm being triggered as follows:
-
If opened with the trunk remote button via the FZV, the GM prevents the alarm from
activating. (This feature is customizable under the Car Memory function).
-
If opened with the key at the trunk lock cylinder the trunk key position switch signals
the GM and in the same manner prevents the alarm from activating.
In either case, when the trunk is returned to the closed position, it is no longer
considered as an activation signal.
Panic Mode Operation: When the trunk button is pressed and held, the GM is signaled
to activate the siren for the Panic Mode. The panic mode is function with either an armed
or disarmed DWA system.
EMERGENCY DISARMING
Emergency disarming occurs automatically if a key is used to turn the ignition switch on and
the EWS accepts it. The EWS signals the GM to unlock the doors and deactivate the DWA.
52
E46 Central Body Electronics
ALARM INDICATION
When the alarm is triggered, the siren will sound for 30 seconds. At the same time the low
beam headlights and four way flashers will flash for 5 minutes. The GM signals the the LSZ
via the K bus to flash the lights.
Following an alarm trigger, the system will reset and trigger again if further tampering is
done to the vehicle.
DWA LED STATUS
DWA STATUS
DWA LED CONDITION
Disarmed
OFF
Armed
Continual slow flash
Armed with one or more monitored
inputs not in closed position
(ie: trunk not fully closed, etc)
Rapid flash for 10 seconds,
then continual slow flash.
Alarm activated
Rapid flash for 5 minutes,
then continual slow flash.
Rearmed in less then 10 seconds.
ON for 1 second
Disarmed after activated alarm
Rapid flash for 10 seconds,
then OFF.
53
E46 Central Body Electronics
FRONT POWER SEATS
SEAT CONTROLS
Located in each seat base are the
respective seat controls.
The switch
modules are contoured to fit behind the
outboard seat base plastic trim. They each
incorporate the seat adjustment switches
and motor control circuitry.
As in the past there are no serviceable
replacement parts (switch levers, switch
buttons, etc.) they must be replaced as a
complete unit if necessary. They differ from
driver's to passenger seats as follows:
DRIVER’S SEAT= SEAT MEMORY CONTROL MODULE (SM)
• In addition to the position switches, the SM also contains the memory position switches
and monitors the seat motor positions via pulsed signals from hall effect sensors in each
driver's seat position motor.
• The SM communicates with the GM and Instrument cluster via the K bus to provide Car
and Key Memory seat adjustment functions.
• The SM is equipped with on board diagnostics which monitor motor circuits for opens,
shorts and not plausible operation. The SM communicates with the DIS or MoDiC for
diagnosis, and car memory encoding.
• The electronics are protected against polarity reversal and excess voltage. A non-volatile
memory maintains memory settings if the SM or battery is disconnected.
54
E46 Central Body Electronics
PASSENGER’S SEAT (without memory)
• The passenger seat control switch is purely a mechanical switching module that activates
the passenger seat motors without position monitoring capabilities.
• Due to it's limited operation requirements, the passenger seat control switch is not
equipped with on board diagnostics.
• The Passenger Seat control switch is equipped with an overload protection function. If
excessive amperage is drawn due to a defective motor or a switch is stuck driving a
motor to its' end limit , the function activates opening the motor control circuit.
KL30
SEAT
SWITCH
SEAT
MODULE
KL30
KL31
KL31
80
60
K-BUS
GMV
3
100
2
40
120
20
140
4
5
6
1
0
D-BUS
7
INSTRUMENT
CLUSTER
55
E46 Central Body Electronics
SEAT POSITION MOTORS
There are either 3 or 4 electric motors in the front seats depending on the seat model.
The motors differ from driver’s to passenger seats as follows:
Driver’s seat motors:
•
Each motor is individually controlled by the SM via a two wire circuit providing motor
activation in both directions.
•
Each position motor incorporates a hall effect sensor that provides a single pulsed
square wave signal for each revolution of the motor. The hall sensor is required for the
memory feature of the driver’s seat and as feedback for motor load protection.
•
When a motor is activated, the
SM also memorizes what
direction the seat switch was
moved to since it can not
determine the exact seat
position based on the hall sensor
signal alone. This is required if
the exact position is needed for
memory storage.
Passenger seat motors:
•
Each motor is individually controlled by the Seat Control Switch.
•
Each position motor is connected to the seat position switch by a two wire circuit
providing motor activation in both directions (no hall effect sensors).
•
Each position motor is connected to the seat position switch by a two wire circuit
providing motor activation in both directions (no hall effect sensors).
56
E46 Central Body Electronics
SEAT MOTOR ACTIVATION
DRIVER’S SEAT ADJUSTMENT
When a position switch
is moved, the control
electronics of the SM
receives an input signal
to move the
corresponding motor
until the switch is
released.
KL30
MOTOR
POLARITY
SWITCHES
The position switch is
also memorized for the
requested direction (ie:
slide forward/slide
backward).
SEAT BASE
(UP/DOWN)
SEAT BASE
(TILT)
The SM includes a
multiplexed switch unit
that handles the
polarity control and
motor selection
simultaneously.
Only one motor can be
activated at a time.
K-BUS
BACK REST
SEAT BASE
(FOWARD/BACK)
KL31
The multiplexer control activates the polarity contacts and then the individual motor
contacts to run the motors individually.
PASSENGER SEAT ADJUSTMENT
Operation of the passenger seat is always possible regardless of key position. Moving a
position switch operates a the motor control contacts directly, The switch applies voltage
and ground path directly to operate the motor. Reversing the switch simply changes the
motor polarity.. More than one passenger seat motor can be run simultaneously.
57
E46 Central Body Electronics
DRIVER’S SEAT MEMORY FUNCTION
As with previous systems, the seat memory feature of the SM stores three seat positions
for recall. The positions are stored in a non-volatile memory preventing loss of positions if
in case the SM or the battery is disconnected.
The additional buttons on the SM (M)
provide activation of recording memory
position and (1-2-3) for storing or recalling a
specific seat setting.
Storing current seat position:
•
•
•
•
Seat in desired position,
Ignition switch in KL R,
Press the M button until it illuminates
Within 7 seconds press the 1,2 or 3
button to store.
The stored position can be recalled at any time by pressing the appropriate memory
location button (1-2-3).
MEMORY RECALL MODES OF OPERATION
Depending on current SM input signals via K-Bus, the memory recall operates in two
distinctly different modes:
•
•
One-touch mode (TTB),
or press and hold mode of operation (DTB).
If the following input signal status is current, the SM resets the seat position by a
momentary “one touch” of the selected memory button.
•
•
Ignition switch off with the driver’s door open, or,
KL R on, door open or closed
If the following input signal status is current, the SM resets the seat position by a continuous
”press and hold” of the selected memory button.
•
•
Ignition switch off with the driver’s door closed
KL 15 on, door open or closed.
58
E46 Central Body Electronics
DRIVER’S SEAT MEMORY (CAR Memory Influence)
The SM can be encoded to recall a specific seat position for a vehicle user when the GM
signals the SM to automatically recall stored positions separate of the 1-2-3 button
selections.
This feature is encoded through the car memory function and activated by the key memory
function. The SM will monitor the seat position and store it in another area of it's memory
when the vehicle is locked with the remote keyless entry system. The GM sends a request
to memorize the seat position and store it for FZV key user 1,2,3 or 4.
If another user of the vehicle changes the seat position the SM restores the memory
position the next time the specific key is used to unlock the vehicle.
This feature can be further modified to activate the position recall based on the owner's
selected activation scenario, for example: The owner can choose to :
•
•
•
Disable this feature,
Initiate memory recall when the unlock signal is initially sent before a door is opened.
Initiate memory recall when the unlock signal is sent but only when the driver's door is
opened.
POWER SEAT DIAGNOSIS
The SM communicates with the DIS or MoDiC via the K bus - instrument cluster gateway
- to the D bus. The SM monitors the seat motors and circuits as well as it's internal
operation. Any detected faults are stored in the SM fault memory and are called up when
diagnosing the system with the Fault Symptom diagnostic plan.
The SM also provides status display to the DIS of its input and output control signals as
well as component activation.
59
E46 Central Body Electronics
E46 CONVERTIBLE FRONT SEATS
Purpose of the System:
The front seats of the E46iC are designed in such a way that all forces acting on the occupants during collision are reduced to the floor pan by the defined design characteristics of
the seat. The front seat also incorporate the Seat Integrated belt System (SGS) and the
“Comfort Entry Aid System”.
Components of the System:
ART-EBODY11
Seat Integrated Belt System (SGS)
The SGS seat is similar in design to the SGS in the E31. The backrest and seat frame are
reinforced to allow the belt system and deflection points to be integrated into the seat. All
of the belt fastening points move with the seat as it is adjusted. This ensures the best possible body strapping irrespective of the seat position or body size. With the short free belt
lengths, the occupants are held quicker with any vehicle deceleration. The SGS design will
cause all forces occurring during a collision to be channeled into the reinforced floor pan.
60
E46 Central Body Electronics
Seat Belt Assembly
The fixed anchor point and seat belt tensioner are mounted on the seat frame. The upper
deflection point of the belt is attached to the head rest which causes the belt to be optimally positioned when the head rest is moved.
The inertia reel locking mechanism is attached to the backrest frame of the seat. It consists of two independent triggering devices which act on the inertia reel.
•
The first triggering device locks the belt during fast cornering, heavy braking,
roll over or during impact.
•
The second triggering device serves as an auxiliary safety lock and is controlled
by the “Mass Moment of Inertia”. The position of the mass moment of inertia is a
decisive factor for the belt to lock.
The inertia reel locking mechanism is connected through a lever and a cable drive to a gear
assembly on the seat back hinge. As the angle of the backrest is adjusted, the gear assembly and cable drive will change the angle of the inertia lock. This ensures that the lock is in
the proper position for locking at any seat back angle.
52460001
61
E46 Central Body Electronics
Comfort Entry Aid
The switch for the comfort entry aid feature is positioned at the top of the seat back. The
switch provides an input to the seat module which activates the seat forward/backward
motor.
When pressed forward, the motor rapidly moves the
seat to its most forward position.
When the switch is pressed rearward, the seat returns
to the previous set position.
When the lever for the backrest is raised and the back
rest is pulled forward, the back rest lock switch provides an input to the seat module. The module activates the head rest motor and it moves down to its
lowest position. When the seat back rest is relocked,
the module activates the head rest motor to return to
its previous set position. This feature will only activate
when the seat is moved forward far enough to cause
the head rest to interfere with the sun visor as the back
rest is pulled forward. The seat module recognizes the
position of the seat base for activation of this feature.
ART-EBODY16
62
E46 Central Body Electronics
ART-E46BODY17
ART-E46BODY15
E46 CONVERTIBLE SEAT MEMORY SYSTEM
Purpose of the System:
The seat memory system uses two control modules on each front seat (driver and passenger). One processor is incorporated into the seat adjusting switch and a second
processor is mounted under the seat. The functions of the two control modules is to
process the following inputs and outputs to control the seat:
•
•
•
•
•
Seat adjustments
Comfort entry aid switch
Seat back rest lock micro switch
Seat belt fastened
K-bus communication with the GM V and Instrument Cluster
As with previous systems, the Driver seat memory feature stores three seat positions for
recall. The positions are stored in the non-volatile memory preventing loss of positions in
case the SM or the battery is disconnected.
Components of the System:
Refer to the Driver’s and Passenger’s memory seat IPO.
System Operation:
The seat adjusting switch block communicates with the control module over dedicated
lines. The output stages for seat motor movement are in the control module. The seat positions are recognized through the use of hall sensors on the motors. All components of the
seat memory system are monitored for faults.
Additional functions of the memory system include memorizing the position of the seat and
headrest when the entry aid feature is activated. The seat will return to its previous set position when the entry aid switch is pressed rearward or the seat back rest is locked.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
63
E46 Central Body Electronics
MEMORY SEAT I P O
* Sport Seats only
Comfort
Entry
64
E46 Central Body Electronics
PASSENGER’S SEAT MEMORY IPO
The passenger’s front seat incorporates a control module for seat adjustment and the entry
aid features. Only the seat forward/back and head rest adjustment motors incorporate hall
sensors for position recognition.
Comfort
Entry
65
E46 Central Body Electronics
COMPONENT LOCATIONS:
52460004
The memory control module for the seat is
mounted under the seat base on the seat
frame.
52460002
Three seat adjustment motors are mounted under the seat base on the seat frame as follows:
TILT
MOTOR
FOWARD/BACKWARD
MOTOR
52460003
66
E46 Central Body Electronics
HEIGHT MOTOR
COMPONENT LOCATIONS:
The backrest adjustment motor is mounted on the lower edge of the backrest frame.
BACKREST MOTOR
52E46SEAT0300
The headrest adjustment motor is mounted at the upper edge of the backrest frame.
HEADREST MOTOR
ART-KT5424
67
E46 Central Body Electronics
MIRROR MEMORY SYSTEM
Purpose of the System:
The function of the mirror memory system is to:
•
•
•
•
Memorize mirror positions,
Adjust mirrors,
Control heaters for the outside mirrors.
Communicate with the Driver’s seat memory module to recall mirror positions.
Components of the System
The mirror memory system consists of the following components:
• Mirror adjusting switch
• Driver’s mirror memory module
• Passenger’s mirror memory module
• Driver’s seat memory module
• Mirrors with adjusting motors and
feedback potentiometer
ART-E46BODY25
ART-E46BODY26
68
E46 Central Body Electronics
System Operation:
Each mirror module is responsible for mirror adjustment, storage of the mirror positions and
mirror heating. Operation of the mirror adjusting switch remains the same for initial setting
of the mirror positions. Feedback potentiometers are used for mirror position recognition for
memory storage purposes. The driver’s mirror module communicates with the passenger’s
mirror module and the seat module over the K-bus.
When a memory position is set with the seat module, a signal is sent to the mirror modules
over the K-bus and the current positions are stored in memory locations 1, 2 or 3 in the
respective modules.
When a memory button is pressed for recall of a stored position, the seat module signals
the mirror modules over the K-bus to return the mirrors to the stored settings.
ART-E46BODY28
69
E46 Central Body Electronics
OPTIONAL SEAT HEATING (1999 M.Y.)
The optionally equipped E46 Seat Heating feature is similar to previous systems with two
preset temperature settings. The seat heating system consists of the following
components:
•
•
Console mounted, temperature regulating seat heater switches.
Two section (Seat base and back) carbon fiber heating pad with temperature sensor. If
seat heating is equipped on the sport seat, a third heating pad is incorporated into the
thigh support.
SEAT HEATING SWITCH
Each seat push-button switch contains two LED's
that correspond with the two preset temperature
settings.
•
Both LED's ON,
Higher
temperature
setting
selected
KL15
•
Left LED ON
only, Lower
temperature
setting
selected
KL31
The
switches
TEMPERATURE
SENSOR
contain
temperature regulation
electronics that provide
100% current flow to
the seat heating
element pad when first
activated providing fast
heat build up. Once the
temperature is attained, the
electronics regulates the current flow to
stabilize the set temperature.
The switches provide operating current to the seat heaters until switched off. There is no
preset time limit of operation.
70
E46 Central Body Electronics
If the battery voltage drops below 11.4 volts, the seat heating switch cuts the power supply
to the heating pads but the LED's in the switch remain illuminated. The seat heating
switches restore power to the heating pads when the battery voltage raises above 12.2
volts for more than five seconds.
CARBON FIBER HEATING PADS
In each seat is a two section (three section on sport seats), heating pad. The sections are
wired in parallel . The heating pads are resistors which when provided operating power
from the seat heating switches produce radiant heat to the following temperatures.
•
•
High temperature setting selected (40OC at heating pad)
Lower temperature setting selected (37OC at heating pad)
The seat base heating element also contains a temperature sensor for feedback to the seat
switch to provide the temperature regulation output control.
DIAGNOSIS
The seat heater switches contain a diagnostic mode of operation that provides a self check
of the system components when activated. The diagnostic information is provided via flash
codes from the LED's.
Diagnostic mode activation:
•
•
•
•
•
•
•
•
•
Switch ignition OFF
Press and hold the suspect seat heating switch button
Switch the ignition ON
Release the heating switch button
Both LED's illuminate steady indicating the seat heating system is functioning.
Within 10 seconds the LED will begin flashing the following codes:
Single flash = Switch faulty due to overheating or short
Double flash = Short or open in temperature sensor or it's circuit.
Triple flash = Heating element shorted
Normal operation of seat heating can only be resumed after cycling the ignition key.
71
E46 Central Body Electronics
CENTER CONSOLE SWITCH CENTER (SZM)
OVERVIEW
From 2000 Model Year, E46 vehicles are
equipped with a new Center Console Switch
Center (SZM).
The SZM directly controls the front seat
heating and provides a diagnostic interface
with the DIS/MoDiC via the K BUS.
SZM also provides a unitized switching center
for Dynamic Stability Control (DSC III),
Convertible Top operation switches and
Harman/Karden sound system button.
The switch signal output for these systems is a direct output signal. All diagnosis functions
are carried out through their respective control systems.
SEAT HEATING OPERATION
The front seat heaters are adjustable through three ranges of heating output temperature.
Pressing the respective seat heater button once
provides stage 1. All three LEDs illuminate and the
heating elements are provided regulated output
current producing a seat temperature of 111OF.
Pressing the button a second time provides stage
2. The top LED switches off and the heating elements are regulated to an output temperature of
102OF. Pressing the button a third time provides
stage 3. The top and middle LEDs are off and the heating elements are regulated to an output temperature of 95OF.
The SZM monitors the seat heating element temperature via an NTC feedback signal to
regulate the output current which maintains the seat temperature.
Seat heating is switched off by pressing the button a fourth time, pressing and holding the
button for more than 1 second or when the ignition is switched off.
72
E46 Central Body Electronics
SZM MONITORING OF SEAT HEATING
Battery Voltage: The SZM switches current supply to the heating elements off when battery voltage drops below 11.4 volts. However, the heating stage LEDs remain on.
Regulated output current resumes when battery voltage raises above 12.2 volts for more
than 5 seconds.
SZM Internal Temperature: The power output stages for the seat heating elements generate a considerable amount of heat when in stage 1 operation. The SZM monitors it’s own
internal temperatures and reduces the heating output when internal temperatures rise to a
temperature of 185OF or switches it off completely above 203OF.
As with battery voltage monitoring, the heating stage LEDs remain on when these temperatures are exceeded.
Fault Monitoring: The SZM monitors the temperature sensors and heating mats for faults.
Detected faults are stored in the SZM. Fault Symptom Troubleshooting in conjunction with
stored faults will initiate the diagnostic paths using the DIS/MoDiC.
The following faults can be recognized:
•
•
•
Shorts or opens in the wiring circuits.
Shorts or opens in the temperature sensors
Open in heating element.
If a short is detected in the temperature sensor, the seat heating is switched off to prevent
overheating. The Stage LEDs are also switched off with this fault present.
73
E46 Central Body Electronics
SZM IPO SCHEMATIC
CHECK
ENGINE
DRIVER’S SEAT HEATING
KL 30 (BATTERY)
-
+
KL 31 (GROUND)
KL 15 (IGNITION ON)
PASSENGER’S SEAT HEATING
KLR (ACC)
58G (PANEL LIGHTING)
BMW DIS
KL 87 (OPERATING POWER)
SZM
80
60
K BUS
40
20
3
100
120 140
100
160
180
80
200
60
220
40
½
0
2
120
140
5
6
0
7
km/h
MPH
40
ELECTRONIC
20 15
10
0
!
miles
CHECK
ENGINE
LSZ
4
1/min
x 1000
1
240
20
OIL SERVICE
INSPECTION
+72.0 f
o
20 DIGIT READOUT
prnd432
m
P
!
ABS
DIS
songaiD
metsyS noitamrofnI dna -e
DIS &
MoDiC
DIS
M
o
D
iC
BMW DIS
BMW
CVM CONTROL
MODULE
HARMAN/KARDEN
AMPLIFIER
DSC
74
E46 Central Body Electronics
DSC III
CONTROL
MODULE
OPTIONAL SEAT BACK LUMBAR SUPPORT
The optional air bladder lumbar support system is similar to the E38/E39 comfort seat.
Each seat contains the following components:
•
•
•
•
Four position circular rocker switch in the seat base trim in the area of the seat switches.
Electrically controlled air compressor with over pressure cut out under each seat.
Two solenoid activated air controlling valve blocks (one per air bladder). Each valve
block includes an inlet and an outlet valve. When energized they direct air into the
bladder(s) to inflate or relieve trapped air to deflate the bladders.
Connecting hoses and air bladders in lower seat back
OPERATION
The lumbar support
system can be operated
at any time regardless of
key position. The four
position circular rocker
switch provides power
switching to operate the
system as follows:
• Position 1: The internal switch contacts provide a power and ground path for both valve
block inlet valves and the air compressor. Both bladders inflate until the switch is
released. If the switch is held continuously, an overpressure bypass valve opens on the
compressor preventing damage to the bladders.
• Position 2: Compressor activated, upper bladder inflates, lower bladder deflates
• Position 3: Compressor activated, lower bladder inflates, upper bladder deflates
• Position 4: Compressor is not activated. Upper and Lower bladders both deflate.
DIAGNOSIS
The seat lumbar support system is purely electro-pneumatic control system. No electronic
diagnostic communication is possible.
75
E46 Central Body Electronics
DUAL POWER/HEATED OUTSIDE MIRRORS
(Sedans produced prior to 9/99 or vehicles equipped with manual seats)
The E46 is equipped with Dual Power/Heated Outside Mirrors and Windshield Washer
Spray Nozzle Heaters as standard equipment. Control of the mirrors is carried out directly
by the mirror switch located in the driver's door handle. The switch also provides power to
the heating element in the driver's door mirror. Passenger door mirror heating element
power supply is provided directly. The mirrors are heated regardless of outside ambient
temperature. The heating element resistance produces a mirror temperature of
approximately 60oC.
The switch utilizes the familiar four way button and a changeover switch. The switch is
provided with operating power (KL 15) and ground.
Each mirror has two motors providing horizontal and vertical adjustment. Pushing the four
way button to an up/down or left/right position activates the corresponding motor.
WINDSHIELD WASHER NOZZLE JET HEATERS
The windshield washer nozzle jet heaters are provided power when the outside temperature
switch closes at 6°C +/- 4°C. The switch open when the temperature raises to 16°C +/4°C.
The outside temperature switch is located on the lower edge (passenger side) of the air
dam.
76
E46 Central Body Electronics
CONSUMER CUT OFF
The interior lights are connected to the consumer cut off circuit. These consumers are
connected to KL 30 and can remain on if one of the control switches are left on. This would
prevent the ZKE from going into the sleep mode. However, the consumer cut off will switch
Kl 30, to the interior lighting, off after 16 minutes (sleep mode active).
To achieve "sleep mode" in the workshop:
• Switch the ignition off
• Close all doors, trunk and hood (mechanically close latches with doors open if necessary
• Central lock vehicle
• Wait 16 minutes
If one of the following signals from the chart below are activated before the vehicle is in
sleep mode, the 16 minute cycle starts again. After the 16 minute wait period, the vehicle
will be in "sleep mode". To bring the system out of sleep mode, the GM responds to a
status change of the signals from the chart below.
SIGNAL
ACTIVITY
ORIGINATING
MODULE
K-BUS
High
General Module
Door jamb sensors (possibility of 4)
Low
“
Trunk lid lock cylinder microswitch
High
“
Interior Trunk lid pushbutton microswitch
Low
“
Central locking button
Low
“
Hood microswitch
Low
“
Trunk Key Position switch (DWA)
Low
“
Interior light switch
Low
“
UIS sensor
Low
“
Tilt Alarm sensor
Low
“
Driver’s door lock sensors-(lock/unlock)
Driver’s door
77
E46 Central Body Electronics
BATTERY STATUS
The GM monitors KL R on a dedicated circuit. If the ignition is switched on and detected
via the KL R circuit but the GM does not receive KL R status via the K Bus, the GM monitors
the KL R voltage level. If after an additional 0.3 seconds there is no K Bus activity, the GM
initiates an emergency running program.
A substitute value for vehicle speed is used to allow the GM to operate certain functions.
The emergency running program will terminate if the GM detects a vehicle speed or KL R
status via the K bus.
DIAGNOSIS/TROUBLESHOOTING
The GM V contains an EEPROM fault memory. Diagnosis and troubleshooting is carried
out with the DIS or MoDiC. The diagnostic link is through the Instrument cluster over the
K bus to the GM.
78
E46 Central Body Electronics
Review Questions
1. List the functions directly controlled by the GM V.
2. How does the GM V communicate with other control modules?
3. What effect does road speed have on the wiper system? What effect does it have on
an AIC equipped vehicle? Where does the road speed come from?
4. How does the GM V recognize the key position from the drivers door? What is the best
way to check those signals?
5. What additional output does the GM V use for the E46 convertible central locking
system?
6. Describe the procedure used by the GM V to recognize an FZV key. Can the GM
differentiate between different keys? How many can it recognize?
7. Explain why the model year 2000 FZV key no longer has replaceable batteries, and
describe the charging process.
8. What “convienience” features are available from the FZV key?
79
E46 Central Body Electronics
9. Describe what happens when the GM V receives the crash signal from the MRS.
10. Why does the SHD (sunroof) module require initialization but the windows do not?
11. How does the GM V signal the tilt sensor, UIS sensor and siren that the alarm system
has been armed?
12. When does the convertible seat “Comfort Entry Aid” system lower the headrest. Why
does the seat base move faster with comfort entry than with the normal switch?
13. What type of sensor is used to detect the position of a seat with Memory? What type
of signal does it produce?
14.How does the Seat Module communicate a request for a stored memory position with
the mirror modules?
15. Where is the outside temperature switch located and what is it used for?
80
E46 Central Body Electronics
Table of Contents
CVM AND CONVERTIBLE TOP
Subject
Introduction
Page
.........................................................................................
3
System Components
Top and Frame ..................................................................................
CVM
.........................................................................................
Hydraulic Unit ....................................................................................
Hydraulic Cylinders ............................................................................
Hydraulic Solenoids ...........................................................................
Storage Cover Motor .........................................................................
Windshield Frame Lock Assembly .....................................................
Top Switch ........................................................................................
Hall Sensors ......................................................................................
Angle Hall Sensors ............................................................................
Compartment Floor Micro Switch ......................................................
4
5
6
7
9
10
11
12
13
19
20
IPO
......................................................................................... 22
System Operation ................................................................................... 23
Emergency Operation ............................................................................. 28
Comfort Operation .................................................................................. 29
Diagnosis
......................................................................................... 30
Hard Top
......................................................................................... 33
Workshop Hints ...................................................................................... 35
CVM Worksheets .................................................................................... 39
Review Questions ................................................................................... 41
Initial Print Date: 02/2000
Revision Date: 1/22/01
CVM AND CONVERTIBLE TOP
Model: E46 Convertible
Production Date: 01/00
Objectives:
After completing this module, you should be able to:
•
Describe the lowering and raising sequence of the Convertible soft top in details.
•
Name all the sensors and their functions that are used to open or close the soft top.
•
Identify and describe electro-hydraulic components used in the Convertible top.
•
Describe the information that is exchanged between the CVM II and the GM V.
•
Describe the operation of the Storage Compartment Cover Lock Motor.
•
Identify all the hall sensors, angle hall sensors and micro-switches used in the soft top.
•
Explain all of the pre-conditions for Convertible soft top operation.
•
Describe the wiring of the Hard Top Locks on the left and right.
•
Diagnosis a Faulted CVM System.
•
Describe the locking / unlocking procedure for the manual soft top.
2
CVM and Convertible Top
INTRODUCTION
Purpose of the System:
The E46 Convertible-top is a fully automatic electro-hydraulic system that completely opens
and closes the soft-top using hydraulic cylinders and electric motors. It consist of the convertible module (CVM II) which controls and monitors the complete operation of the system.
The CVM II interacts with the General Module which controls the operation the convertibletop storage compartment cover and window operation when lowering or raising the softtop.
Convertible top features:
• Electro-hydraulic operation.
• Comfort opening using FZV key or door lock cylinder.
• Comfort closing using only the door lock cylinder (No anti-trap protection).
• Glass window
• Top operation monitored using hall sensors and hall angle sensors.
Convertible Top
Module
Hydraulic Unit
w/ Solenoids
General Module
Storage Cover Unlock Motor
Top and Frame
Top Switch
Solenoid Valve
Block
ART-E46ICBODY
3
CVM and Convertible Top
Components of the System:
Top and Frame
The top frame is similar to the E36iC with modifications for the adoption of the hydraulic
cylinders used for raising/lowering the top. The unlock motor and gear drive assemblies are
attached to the front of the top frame as on the E36iC.
The convertible top consists of three layers:
•
The outer layer is fabric with a non-replaceable glass rear window.
• A middle fleece liner is installed between the fabric and inner liner for sound and
weather insulating purposes.
• The inner liner is similar to the E36iC and is attached to the top frame so that it
stretches tight when the top is closed.
OUTER FABRIC
FLEECE LINER
INNER LINER
ART-TOPLAYERS
4
CVM and Convertible Top
Convertible-Top Module (CVM II)
The convertible-top module (CVM II) is installed in the left rear quarter panel behind the interior trim panel. It contains the processing, controlling and monitoring electronics for the
complete top operation. The CVM II communicates with the GM over the K-Bus for operation of the top storage cover and windows.
Operation of the hydraulic cylinders is controlled via final stages and solenoids mounted on
the hydraulic unit and top frame.
The CVM is fully diagnoseable and contains a fault memory for storage of monitored faults.
Diagnosis is carried out over the K-Bus with the DIS or MoDiC.
CVM II
61E46CVM0300
CVM II
61E46CVM0400
5
CVM and Convertible Top
Hydraulic Unit
The hydraulic unit is mounted in the trunk on the left side behind the trim cover. It is mounted on a rubber bushing and covered by sound insulation for noise reduction during pump
operation. The hydraulic unit consists of:
•
•
•
•
•
Motor,
Pump,
Storage Cover Solenoid Valve/ Drain Solenoid Valve
Reservoir.
Temperature Sensor - hydraulic fluid
The hydraulic unit provides an operating pressure of up to 200 bar for the tops operation.
A temperature sensor on the hydraulic unit will signal the top module to cease operation if
the fluid temperature exceeds 95 C. Any function started will be completed before the system is switched off. If the temperature exceeds 105 C, the system is immediately switched
off and the emergency closing procedure will be required for closing the top.
0
0
When the temperature drops below 950, the operation of the top can be resumed.
54HYDRAULICPUMPE46050
Filling or checking the hydraulic fluid is only carried out when the top is lowered in the storage compartment. The recommended fluid is “ARAL VITAMOL” PN 54 34 8 410 000 (Refer
to the repair manual for filling procedures)
6
CVM and Convertible Top
Hydraulic Cylinders
Top Storage Compartment Cover
Two hydraulic cylinders are positioned on the left and right sides in the trunk for opening
and closing the top storage compartment cover. A Hall sensor is positioned on the left
cylinder to detect the full opened position of the cover.
Cylinder Removed
Cylinder Installed
Hall Sensor
ART-KT5355
54E46CYLINDER0900
Tensioning Bow (Clamping Bracket)
Two hydraulic cylinders are positioned on the left and right sides of the tensioning bow, on
the top frame linkage for raising and lowering the bow. An angle hall sensor is installed on
the left tensioning bow linkage to detect the positioning of the bow. The hydraulic lines for
the right side tensioning bow cylinder are routed under the top fabric along the tensioning
bow.
54E46CYLINDER1200
54E46CYLINDER1300
7
CVM and Convertible Top
Main Pillar
Two hydraulic cylinders are positioned on the left and right sides of the top frame linkage
for raising and lowering the soft top frame. An angle hall sensor is used to detect the positioning of the main top linkage. The hydraulic lines for the right side main pillar cylinder are
routed under the top fabric along the tension bow.
54E46MAINPILLAR1100
54E46MAINPILLAR1000
A gas filled piston strut is mounted on the right side frame linkage, next to the hydraulic
cylinder, to dampen the raising and lowering of the top frame.
Gas Strut
54E46GASSTRUT0800
8
CVM and Convertible Top
Hydraulic Solenoids
Two hydraulic solenoids are mounted on the hydraulic
unit:
•
One solenoid valve (V1: I01043 convertible top
cover) controls the opening and closing of the
storage compartment cover
•
The second solenoid valve (V5: I01061, pressure
deactivation) is the drain solenoid for relieving
pressure in the hydraulic cylinders when the key is
switched off. The drain solenoid also holds system
pressure when the top switch is released during
operation.
54E46HYDRAULICCONNECTOR0600
Three hydraulic solenoids are mounted on the valve
block on the left side of the top frame.
•
Solenoid valve (V2: I01027, extend main pillar)
controls the operation of the main pillar hydraulic
cylinder.
•
Solenoid valve (V3: I01028, extend tensioning bow)
controls the tension bow hydraulic cylinders for
lowering.
•
Solenoid valve (V4: I01029, retract tensioning bow)
controls the tension bow hydraulic cylinders for
raising.
ARTSOLBLOCK
9
CVM and Convertible Top
Top Storage Compartment Cover Lock Motor
The top storage compartment cover lock motor is located on the drive shaft tunnel under
the rear seat. It consists of the motor with a hall sensor (S700), gear linkage assembly and
two bowden cables. Two locks are located on the right and left sides for locking the storage compartment cover. The lock motor hall sensor (S700) detects the locked/unlocked
position of the storage cover.
During the soft top operation, when the tensioning bow is raised or when the top is in the
storage compartment, the CVM signals the GM over the K-Bus to unlock the storage compartment cover. The GM activates the lock motor and the motor turns 180 degrees to
unlock the cover latches. The motor always turns in the same direction to unlock/lock the
cover.
Once the motor has turned 180 degrees, the hall sensor (S700) input signal will cause the
GM to switch off the motor. At the same time, the GM will signal the CVM to continue top
operation.
Convertible
Top Cover
Drive Switch:
S700
ART-KT-5380
10
CVM and Convertible Top
ART-KT5382
Windshield Frame Lock Assembly
The windshield frame lock assembly consists of the top lock motor positioned in the center of the top frame and two lock drive mechanisms positioned on the left and right sides
of the top frame. The operation of the lock motor and drive mechanisms is similar to the
E36 fully automatic top system. The drive mechanisms have been redesigned for smoother
operation, however they still are responsible for unlocking the top from the windshield and
raising the front of the top past the tension point. Flexible drive shafts are used activate
the lock assemblies and drive the tension linkage rods to raise the top past the tension
position.
ART-TOPLOCKMOTOR
Right Lock Drive
ART-TOPLOCKRIGHT
Left Lock Drive
ARTOPLOCKLEFT
Two hall sensor switches located on the left lock drive assembly are used to detect the
position of the top against the windshield frame.
11
CVM and Convertible Top
Convertible Top Switch
The convertible-top switchs are located in the Center Console Switching Center (SZM).
There are two push button switches, one for each direction of travel, that provide a ground
input signal to the CVM for top operation.
Two LEDs are positioned in the center of the switch. The top LED will flash whenever the
top is in operation and not locked to the windshield frame or stored completely in the
compartment. The lower LED will illuminate, if the top switch is pressed and the storage
compartment floor is in the “UP” position.
CLOSE ROOF
OPEN ROOF
54E46covswitch0100
ART-E46ICCVMTOP
12
CVM and Convertible Top
Sensors and Switches
The hall sensors, hall angle sensors and micro switches provide feedback status to the
CVM and GM for soft top positioning and top sequencing during operation.
Hall sensors:
• Locking Hook Closed (cowl locked) hall sensor: S142
• Locking Hook Open (cowl released) hall sensor: S145
• Two Top Storage Compartment Cover Locks hall sensors: S161 and S158
• Top Storage Compartment Cover hall sensor: S188
• Top Storage Compartment Cover Motor hall sensor: S700
• Hard Top Lock hall sensor: S164
Angle Hall sensors:
• Tension Bow (clamping bracket) hall angle sensor: I01026
• Main Pillar hall angle sensor: I01025
Micro Switch
• Top Storage Compartment Floor micro switch: S239
Component
Locations
Hall Angle Sensor:
I01026
Hall Sensors:
S142
S145
Hall Angle Sensor:
I01025
Hydraulic Unit
Hydraulic Solenoid
Valve Block
Hall Sensor:
S700
Top Switch
Hall Sensor: S161
Micro-switch:
S239
Hall Sensors:
S158
S164
Hall Sensor:
S188
E46ICTOPUP.
13
CVM and Convertible Top
Windshield Frame Lock Drive Hall Sensors
Two hall sensor switches are installed on the left side top lock drive assembly. Both sensors receive power and ground from the CVM. One switch is the soft top locked to the
windshield frame (S142 cowl locked/locking hook closed). The second switch is the
locking hooks of the convertible top open (S145 cowl released/Locking hook open). As
the slide assembly on the worm gear moves, it covers and uncovers the hall sensors to
cause the high/low switching to take place.
The “Locking hook closed” (S142) input provides a high signal when the top frame is locked
and a low signal when it is unlocked from the windshield (LED in the soft top switch will start
to flash).
The “Locking hook open” (S145) input provides a high signal when the top frame is raised
past the tension point.
Locking Hook Closed Sensor
S142, Cowl Locked
(Locking Hook Closed)
Locking Hook Open Sensor
S145, Cowl Released
(Locking Hook Released)
ART-HALLSENSORSTOPLOCK
ART-E46ICCVMHALL2X
Note: The Diagnosis Requests list in Control Unit Functions refers to a “CONVERTIBLE TOP LOCKED” switch
input (S141). That display is a redundant signal from switch S142. Production E46 Convertibles are not fitted with S141.
14
CVM and Convertible Top
Storage Compartment Cover Lock Hall Sensors
There are two storage compartment cover lock hall sensor switches (S161: right, S158:
left) one mounted on each storage cover lock. The sensors receive power and ground from
the CVM. Each sensor input provides a high signal when the cover is unlocked and the
cover is raised by the hydraulic cylinders far enough to clear the latches.
When the storage cover is completely lowered by the hydraulic cylinders, the hall sensors
send a signal to the CVM. The CVM then signals the GM to re-lock the storage cover.
54E46COVERLOCK0700
S158
Left Side lock
S161
Right Side lock
ART-TPCVRLCK.CVM
15
CVM and Convertible Top
Storage Compartment Cover Hall Sensor (S188 Convertible Top Open)
The storage cover hall sensor switch (S188) is mounted on the left side storage cover
hydraulic cylinder in the trunk. It receives power and ground from the CVM. The switch
provides a high signal input when the top storage cover is fully open.
The CVM uses the signal from the switch for top storage cover positioning and switching
operation during soft top lowering and raising. The CVM uses this input signal as a switching point for activating the tensioning bow solenoid (V3) during top lowering or activation of
the main pillar solenoid during top raising.
Trunk-Left Side
S188: (Convertible Top
Open sensor)
ART-KT-5355
S188
Convertible
Top Open
ART-E46ICCVMRAMROD
16
CVM and Convertible Top
Storage Compartment Cover Motor Hall Sensor (S700 Switch, Convertible Top
Cover drive)
The storage cover motor hall sensor (S700) is mounted on the gear drive assembly of the
motor. It receives voltage from the General Module.
The GM uses this input to switch the unlock motor “OFF”. Additionally, the GM will electrically lockout the trunk any time the storage cover is unlocked. The CVM receives a signal
over the K-bus of the unlock/lock status of the storage compartment cover.
S700
Convertible Top
Cover Drive Sensor
ART-COVERLOCK
5V
S700
Convertible
Top
Cover
E46ICGM12V.
17
CVM and Convertible Top
Hard Top Lock Hall Sensor (S164 Switch, Hard Top Recognition)
The hard top recognition hall sensor is positioned on the left hard top lock. It receives
power and ground from the CVM and provides a high signal input when the hard top is
installed on the vehicle. The connector on the top of the lock is used as the power and
ground supply for the rear window defroster of the hard top.
The CVM uses the input signal of the hall sensor to lock out soft top operation while the
hard top is installed.
ART-MV563
54E46CVM1400
S164
Hard Top
Recognition
HRDTPLCK.CVM
18
CVM and Convertible Top
Tensioning Bow (Clamping Bracket) - Hall Angle Sensor
(I01026 Position Switch, Tensioning Bow)
The angle sensor for the Tensioning Bow is mounted on the left side of the top linkage by
the Tensioning Bow hydraulic cylinder. The angle sensor receives power (5 volts) and
ground from the CVM. It provides a linear voltage signal input from approximately 0.5 to
3.5 volts as the Tensioning Bow moves from a vertical to horizontal position.
The CVM uses the signal from the Tensioning Bow angle sensor to determine positioning
of the tensioning bow and switching operation during soft top lowering and raising.
61E46ANGLEHALLSENSOR0500
I01026 Position Switch
Tensioning Bow
ART-E46ICTENBOW.
19
CVM and Convertible Top
Hall Angle Sensor - Main Pillar
(I01025 Position Switch, Main Pillar)
The angle sensor for the Main Pillar is mounted on the left side top linkage by the left main
pillar hydraulic cylinder. The angle sensor receives power (5 volts) and ground from the
CVM. It provides a linear voltage signal input from approximately 0.5 to 3.5 volts as the top
frame is lowered into and raised out of the storage compartment.
The CVM uses the input signal from the Main Pillar angle sensor for top frame positioning
I01025
Position
Switch, Main Pillar
ART-MNPIHS
I01025 Position Switch
Main Pillar
E46ICMAINPILL
20
CVM and Convertible Top
Storage Compartment Floor Micro-Switch
(S239 Switch, Convertible Top Compartment Floor)
The Storage Compartment Floor micro-switch is installed on the hinge of the compartment
floor on the right side. It provides a high/low input signal to the CVM based on the position of the compartment floor.
When the floor is in the raised position, the soft top operation is locked out.
ART-KT5433
S239 Convertible Top Compartment
floor Switch
ART-E46ICCVM12V.EPS
21
CVM and Convertible Top
CVM IPO
TRUNK LOCK ACTUATOR
KL 30
KL R
TRUNK
LIGHT
TOP SWITCH
CONVERTIBLE TOP
COVER DRIVE HALL SENSOR:
S700
58 g
COMPARTMENT FLOOR
MICRO-SWITCH: S239
CVM
K-BUS
GM V
K18363
CONVERTIBLE TOP
RELAY 1
ANGLE SENSOR
TENSIONING BOW: I01026
HALL SENSORS
DISplus
MoDiC
DIS
M
oD
BMW DIS
BMW
KL 30
iC
ANGLE SENSOR
MAIN PILLAR: I01025
BMW DIS
STORAGE COVER
LOCKED LEFT: S158
STORAGE COVER
LOCKED RIGHT: S161
MAIN PILLAR SOLENOID: V2
TENSIONING BOW SOLENOID
EXTEND: V3
TENSIONING BOW SOLENOID
RETRACT: V4
STORAGE COVER OPEN: S188
LOCKING HOOK ,
CLOSED: S142
STORAGE COVER
MOTOR
I01042
CONVERTIBLE TOP
DRIVE RELAY
LOCKING HOOK,
OPEN: S145
KL 30
HARD TOP
LOCK: S164
HYDRAULIC
UNIT
STORAGE
COVER SOLENOID: V1
DRAIN SOLENOID: V5
KL 31
ART-E46ICEHYDD.EPS
22
CVM and Convertible Top
System Operation
Pre-Conditions for Soft Top Operation
• Ignition key in position “R” - (Except for comfort operation)
• Road speed < 2.5 MPH
• Hydraulic unit temperature < 95 degrees
• Trunk lid closed
• Top storage compartment floor in lower position with top raised
• No hard top installed with top lowered
In addition, there must be no faults present at
any of the switch inputs or outputs.
Top Lowering Sequence
Top Switch Pressed “Open”
•
CVM activates the top lock motor and the
top is unlocked and raised past the tension
point (LED switch flashing).
•
At the same time, the CVM signals the GM
to lower the windows (if closed) for
approximately 1.5 seconds.
•
ART-TOPDOWN1
Top lock motor is switched OFF - signal from cowl released hall sensor (S145).
23
CVM and Convertible Top
•
CVM activates hydraulic pump and switches the tension bow solenoid (V4) to raise the
tension bow.
•
Tension bow is raised to its vertical position - signal from tensioning bow angle hall
sensor.
•
CVM signals GM to unlock storage compartment cover.
•
Storage compartment cover unlocked - signal from motor hall sensor (S700) - storage
cover lock motor is switched off.
•
CVM receives status of cover lock from GM over K-bus - switches storage cover
solenoid (V1).
•
Storage cover raised to its open position signal from cover hall sensor (S188).
•
CVM switches to the lowering solenoid for the
tension bow (V3) - top starts lowering into
storage compartment.
•
CVM switches the main pillar solenoid (v2) top is fully lowered into storage
compartment.
54E46TOPLOWERING0000
ART-TOPDOWN3
24
CVM and Convertible Top
•
CVM switches solenoid for top cover (V1) - cover is lowered - signal from storage cover
lock hall sensors (S161 and S158).
•
CVM signals GM to lock storage compartment cover.
•
GM activates cover lock motor - cover is pulled closed by lock assemblies.
•
GM switches off lock motor - signal from motor hall sensor (S700).
•
CVM switches off hydraulics and LED.
ART-TOPDOWN4
Top Raising Sequence
Top Switch Pressed - “Closed”
•
•
•
•
•
•
•
•
•
•
Windows are lowered (if closed) - CVM to GM
Storage compartment cover is unlocked - CVM to GM
Storage cover is opened
Top is raised out of storage compartment
Tension bow is raised
Storage cover is closed
Storage cover is locked - CVM to GM
Tension bow is lowered
Top is lowered and locked to cowl - Top locked, is confirmed by S142 and Tensioning
bow angle sensor (Tensioning bow horizontal)
Windows are closed - if switch is held
25
CVM and Convertible Top
Hydraulic System Operation
The pump in the hydraulic unit is energized by the CVM and supplies hydraulic fluid under
pressure to the solenoids mounted on the pump and solenoid valve block. The solenoids
are energized by the CVM and the pressure is supplied to the hydraulic cylinders, based on
the input signals from the angle hall sensors and hall switches. The hydraulic operation of
the solenoids and cylinders is as follows:
• The storage cover cylinders receive hydraulic pressure on the lowering side of the piston
ram when the hydraulic pump is energized. When the solenoid is energized, hydraulic pressure is applied to the raising side of the ram. The cover is opened because the greater raising pressure overcomes the pressure on the small side of the ram. When the cover is lowered, the solenoid switches to drain and the lowering pressure closes the cover.
• The main pillar cylinders receive hydraulic pressure on both sides of the ram when the
pump is switched on. The main pillar solenoid is switched to drain to lower the top frame
into the storage compartment. The solenoid is switched to pressure to raise the top frame
out of the storage compartment. The greater pressure on the raise side of the piston will
overcome the lowering pressure to raise the frame.
• The raise tension bow solenoid is energized to apply pressure to the tension bow cylinders and raise the tension bow. The tension bow lower solenoid is switched to drain.
• The lower tension bow solenoid is energized to supply pressure to the tension bow cylinders to lower the tension bow. The tension bow raise solenoid is switched to drain.
• The drain solenoid is energized whenever the pump is switched on. It holds pressure in
the system when any of the cylinder solenoids are not energized. It also holds pressure in
the system if the top switch is released during operation.
The drain solenoid is switched when the hydraulic pump is switched off as the top reaches one of its end positions. This allows the pressure in the cylinders to be relieved and
drained back to the reservoir.
The drain solenoid switches off as the key is switched off. This will cause the pressure to
drain slowly in steps.
26
CVM and Convertible Top
Hydraulic System Operation
ART-E46ICCVM.EPS
ART-E46IC E HYD.EPS
27
CVM and Convertible Top
Emergency Operation
Emergency locking/unlocking of the top storage cover is carried out at the motor assembly.
The motor assembly is accessed by removing
the center arm rest and lifting the seat upholstery below the ski bag.
ART-KT-5384
Pressing the button on the motor assembly will
release the motor from the gear linkage.
Release Button
ART-KT5379
The linkage assembly can then be turned,
through the access hole in the motor assembly
cover, using the hand crank stored on the
assembly cover. This will unlock/lock the storage cover locks for manually raising the top.
Manual
Crank
ART-KT-5380
28
CVM and Convertible Top
Comfort Closing/Opening
Comfort closing/opening of the top is possible at the driver’s door lock cylinder. If the key
is held in the locking position the top will be raised and the windows closed in the raising
sequence.
If the Variable Storage Compartment floor is in the raised position only the windows will be
lowered during the convenience opening sequence.
Residual Closing/Opening
It is possible to finish raising or lowering the top at speeds > 2 MPH if:
•
•
The signal from the main pillar angle sensor indicates that the top is fully extended out
of the storage compartment.
The signal from the main pillar angle sensor indicates that the top is fully lowered in the
storage compartment.
Safety in the Intermediate Positions
All movements of the top stop once the switch is released. The hydraulics hold the position
of the top and remain under pressure for approximately 20 minutes if the ignition key is left
in the ON position.
If the ignition is switched OFF, in the intermediate position, the pressure will be released in
steps after approximately 10 seconds until all pressure is drained from the cylinders. This
allows the top to be manually moved for servicing procedures.
NOTE: Depending on the position, the top may collapse into the storage compartment if
the ignition is switched off with the top in the partially raised position.
29
CVM and Convertible Top
Fault Memory
The fault memory of the CVM is stored in an NVRAM which can store up to a maximum of
16 faults. The fault are stored in the order of occurrence and a distinction is made between
permanent and sporadic faults.
Operation in the Event of Faults
If a fault occurs during raising or lowering the top, all movement will cease and the fault will
be stored in the fault memory. The emergency closing procedure must be used to close the
top and the vehicle taken to the dealership for repair.
Depending on the location and type of fault, it may be possible to raise or lower the top fully
by pressing the switch in the opposite direction from which the fault occurred.
If the top switch is held > 20 seconds after completing a raising/lowering procedure, a fault
will set in the CVM. The control module assumes a fault to ground in the switch or lead. The
ignition switch must be cycled to clear the fault before the top will again function. The fault
will remain in the module until cleared with the Tester or MoDiC.
All sequenced movements of the top have time out limits set in the control module. If a time
out occurs before the end position is reached, the specific movement will be switched off
to prevent damage to any of the top components.
30
CVM and Convertible Top
E46iC MANUAL TOP
The E46iC - 323/325 models are equipped with a manual top as standard equipment.
Raising or lowering the top frame assembly is carried out by hand. However, the manual
top features an electrically operated storage cover lock system. The unlocking/locking of
the storage cover is a function of the general module.
The frame of the manual top is similar to the fully automatic system, with two piston
dampers mounted on the assembly to aid in its operation. The front of the top frame features a manual handle that is used to operate the cowl locks on the left and right sides.
MANUAL TOP STORAGE COVER OPERATION
The storage cover locking assembly consists of the following components:
• General Module
• Switch assembly
• Storage Cover Motor assembly - with hall sensor and bowden cables
• Two Storage Cover Locks - with a hall sensor
• Variable Top Storage Compartment Floor - micro switch
When the button is pressed to unlock the storage cover, the GM will lower the windows and
activate the relay to unlock the storage cover. After raising the tension bow, the storage
cover is raised manually and the top is lowered into the storage compartment. The storage
cover is then lowered onto the locks and the signals from the storage cover hall sensors
will signal the GM to relock the cover.
The signal from the variable storage compartment floor micro switch will prevent the storage cover from opening when the floor is in the open position.
The GM will lock out the operation of the storage cover lock motor whenever the trunk is
opened.
31
CVM and Convertible Top
Manual Top Storage Cover Operation Diagram
Compartment Floor Micro Switch
Top Switch
KL30
Trunk Lock
M
KL 5 8 G
GM V
KL30
Hall Sensor Storage Cover
Hall Sensor Cover MTR.
M
Storage Lock Motor
61460014
32
CVM and Convertible Top
Hard Top
An accessory hard top is available for the E46iC. It is constructed from aluminum with a
finished fabric upholstery on the inside. Roof rack mounting points are integrated into the
top on the left and right sides.
ART-HARDTOP
The hard top attaches to the vehicle at four places:
• Two hard top locks on the left and right sides in the rear.
• Two cowl locks at the front.
ART-HLOCK1
ART-HRT-HLOCK2
33
CVM and Convertible Top
The hard top locks on the left and right, in the rear, have integrated wiring connectors for
power and ground supplies to the rear window defogger and interior lights.
The connector on the left side contains two
separate strips, one for power supply to the rear
defogger and the other for power supply to the
interior lights
ART-HARDTOPLOCKLEFT
The connector on the right side contains two
separate strips, one for the ground connection
for the rear defogger and the other for
ART-HARDTOPCONN
Ground &
GM V control
Power &
GM V control
ART-KT5260
ART-HARDTOP2
34
CVM and Convertible Top
ART-HARDTOP2
Workshop Hints:
Convertible Removal/Installation Top
This section of the handout will cover highlights of soft top removal and installation. The
“REPAIR MANUAL” should always be referenced for the complete procedure on top
removal/installation and adjustments. Removal of the soft top assembly requires removing
the rear seat and interior trim panels to gain access to the fastening points and wiring connections.
Bowden Cable
The top storage cover should be removed prior
to removing the top assembly. The hard top
lock post and storage cover locks must be
removed from the top frame assembly. The
cover locks are connected to the unlock motor
through a bowden cable that must be disconnected when removing the lock assemblies.
The top and frame assembly is bolted to the
main top bracket at four points. The top must
be raised with the tension bow in the vertical
position to access three of the nuts.
ART-FRBOLLOC
Fastening Points
The fourth mounting point for the top frame
assembly is on the front of the top mounting
bracket. This should be loosened after the top
is lowered into the storage compartment.
ART-FRBOLLOC1
35
CVM and Convertible Top
The supply and drain lines from the hydraulic
unit to the solenoid block on the top frame are
connected through quick disconnect couplings
located on the left side of the top storage compartment. Care should be taken when disconnecting the lines not to drip the hydraulic fluid
onto the top fabric.
ART-HYDLINES
Ensure that all wiring is disconnected from the top frame before removing the top assembly. There are three connectors on each side of the top assembly in front of the top storage compartment. The main wiring harness (18 Pin ELO) from the CVM to the top frame
must also be disconnected.
THE TOP FRAME IS UNBOLTED FROM THE FRAME MOUNTING BRACKETS, MOUNTED IN THE STORAGE COMPARTMENT. THESE BRACKETS ARE PRE-SET AND
ADJUSTED FOR TOP ALIGNMENT AT THE FACTORY AND MUST NOT BE REMOVED OR
ADJUSTED WHEN CARRYING OUT SERVICE WORK ON THE TOP.
Frame Bracket
Set at Factory
ART-TOPFRAMECON
Service Adjustments
The convertible top storage compartment cover is made of magnesium, a spacer plate
must be used when installing the cover to the mounting brackets. the brackets have elongated holes for adjustment of the cover to the body.
ART-ANTEMP
ART-SHIM.
The height of the rear of the storage compartment cover is adjusted at the mounting brackets for the hydraulic cylinders located in the trunk. This adjustment must be carried out by
removing the rear tail light assemblies due to the lock out of the trunk lid and storage cover.
37
CVM and Convertible Top
The front of the storage compartment cover is adjusted at two places. The latch brackets
are mounted through elongated holes for alignment of the brackets to the cover latches.
Latch Bracket
ART-KT4956
The front of the storage compartment cover’s height is adjusted by adjusting the bowden
cable length at the storage cover lock motor. The cover should close flush with the body.
Bowden Cable
Adjustment
ART-COVERLOCK
38
CVM and Convertible Top
NAME OF SIGNAL OR FUNCTION: Hall sensor inputs to the CVM
Vehicle: E46iC
M Y: 2000
System: Convertible Top - CVM
#1. Cowl Lock/Tension Point Hall Sensors:
The Cowl Lock input to the CVM is at pin# ____________ and pin# _____________.
The signal from the cowl lock sensor is _____________ volts with the top locked to the
cowl.
The signal from the cowl lock sensor is _____________ volts when the top is unlocked from
the cowl.
The status display on the DIS shows __________________ when the top is locked to the
cowl and ________________________ when the top is unlocked.
The Tension Point input to the CVM is at pin# _________ and pin# ____________.
The signal from the tension point sensor is ___________volts with the top locked to the
cowl.
The signal from the tension point sensor is ___________ volts when the top lock motor
switches off.
The status display on the DIS shows __________________ when the top is locked to the
cowl and ________________________ when the top lock motor switches off.
#2. Storage Cover Lock Hall Sensors:
The storage cover lock inputs to the CVM are at: pin# _______ and pin# ________ LEFT
pin# ______ and pin# ________ RIGHT
The signal from the storage cover lock sensor is _________ volts when the cover is closed
and locked.
The signal from the storage cover sensor lock is _________ volts when the cover is
unlocked.
The status display on the DIS shows ____________________ when the cover is closed and
locked and _______________________________ when the cover is unlocked.
#3. Storage Cover Hall Sensor:
The storage cover input to the CVM is at pin#____________ and pin # ___________.
The signal from the storage cover sensor is _________ volts when the cover is closed.
The signal from the storage cover sensor is _________ volts when the cover is open.
The status display on the DIS shows ________________________ when the cover is closed
and ________________________________ when the cover is open.
39
CVM and Convertible Top
NAME OF SIGNAL OR FUNCTION: Angle Hall Sensor inputs to CVM
Vehicle:
E46iC
M Y: 2000
System: Convertible Top - CVM
#1. Main Pillar Angle Hall Sensor:
The power supply for the main pillar angle hall sensor is ________ volts at pin # ________ of
the CVM and ground at pin # ______ of the CVM.
The input signal to the CVM from the main pillar sensor is _________ volts with the top fully
raised and _________ volts with the top lowered into the storage compartment.
The status display on the DIS of the main pillar sensor input is ______________________
with the top fully raised and _____________________________ with the top lowered into the
storage compartment.
#2. Tension Bow Angle Hall Sensor (Clamping Bracket):
The power supply for the tension bow angle hall sensor is _________ volts at pin # ______
of the CVM and ground at pin # ______ of the CVM.
The input signal to the CVM from the tension bow sensor is:
___________ volts with the top locked to the cowl.
___________ volts with the tension bow in the vertical position.
___________ volts with the tension bow lowered into the storage compartment.
The status display on the DIS of the tension bow input is:
__________________________ with the top locked to the cowl.
__________________________ with the tension bow in the vertical position.
__________________________ with the tension bow lowered into the storage compartment.
40
CVM and Convertible Top
Review Questions
1. What are the major changes to the E46iC fully automatic top operation compared to the
E36iC?
2. How many hydraulic solenoids are used in the operation of the E46iC top?
3. The locking/unlocking function of the storage compartment cover is controlled by which
module?
4. Which hall sensors control the flashing of the LED in the top switch?
5. What happens to the soft top/frame if the ignition is switched off during its operation?
6. Describe the emergency closing procedure for the soft top:
7. What type of input is provided by the angle hall sensors for top operation?
8. The only micro switch used in the operation of the soft top is?
9. What indication is shown if the variable compartment floor is open when the top switch
is pressed?
41
CVM and Convertible Top
Table of Contents
PASSIVE SAFETY SYSTEMS
Subject
Page
MRS II. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Head Protection System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Triggering Logic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Battery Safety Terminal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Diagnosis and Service Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . .8
MRS III. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Components
MRS III Control Module. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
Satellite Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Driver’s Front Airbag. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Passenger’s Front Airbag. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
Side Airbags. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Head Protection System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Battery Safety Terminal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Seat Belt Tensioners. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Seat Occupancy Sensor (SBE). . . . . . . . . . . . . . . . . . . . . . . . . . . 18
MRS III Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Triggering Thresholds (two stage airbags). . . . . . . . . . . . . . . . . . . . 20
MRS III I.P.O.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Triggering Thresholds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
RPS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Components
Roll Over Bar Cassettes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Roll Over Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Diagnosis and Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Initial Print Date: 7/98
Revision Date: 12/03/00
Multiple Restraint System II (MRS)
Model: E46/4
Production Date: 6/98 to 9/99
Objectives
After completing this module you should be able to:
• Identify the components used in the MRS II system.
• Describe the operation of the ITS.
• Understand the triggering logic used by MRS II.
• Describe the operation and repair procedure for the BST.
2
Passive Safety Systems
MULTI-RESTRAINT SYSTEM (MRS II)
The MRS II passive safety system is standard equipment on all 1999 M.Y. E46 models. The
system is a carry over from the MRS II system introduced on 98 Model Year E38/E39s.
The MRS II system for the E46 consists of the following:
•
•
•
•
•
•
•
•
•
•
MRS II Control Module
Driver and passenger's front air bags
Driver and passenger's side air bags (thorax)
Driver and passenger's Head Protection System (ITS)
Front pyrotechnic seat belt tensioners
Rear passenger's side air bags (thorax)
Battery Safety Terminal (BST)
Hall effect seat belt switches
Front passenger's seat sensor (SBE)
Driver and passenger's side impact sensors
3
Passive Safety Systems
HEAD PROTECTION SYSTEM (ITS)
The ITS consists of a hermetically sealed rubber tube that is encapsulated by a cross
woven tubular nylon material. Each ITS is mounted from the "A" pillars to the roof panel just
behind the "B" pillars by a nylon strap and mounting bolt.
When deployed, the inflation charge causes the diameter of the ITS to expand and its
length to shorten. As the length shortens, it is forced out of its stowed position of the roof
lining and it extends over the glass to protect the driver or passenger's head.
The ITS remains inflated for approximately seven to eight seconds to extend the protection
time should the vehicle encounter additional side impacts during the crash.
ITS TUBE
4
Passive Safety Systems
MRS II TRIGGERING LOGIC
FRONTAL IMPACT: - Deployment of the front air bags and/or seat belt tensioners is
dependent on the severity of the impact as detected by the internally mounted crash sensor of the MRS II control module.
Additionally, the MRS II looks at the input from the SBE for deployment of the passenger's
front air bag.
Deployment of the seat belt tensioners is also dependent on the presence of a signal from
the seat belt switches.
SIDE IMPACT: - Deployment of the Side impact air bags and head protection (tubular
structures) is dependent on the severity of the impact as detected by the MRS II control
module and the side impact sensors. Generally only the impacted side will be triggered.
The tubular ITS structures and rear side air bags will always be deployed with side air bags.
5
Passive Safety Systems
BATTERY SAFETY TERMINAL (BST)
The BST is an encapsulated pyrotechnic device. It is designed to prevent short circuits from
occurring in the battery power supply to the engine compartment during impacts or collisions.
The ignitor capsule of the BST will be triggered, by the MRS II control module, with any front
air bag activation.
The BST may be triggered with a side or rear impact, depending on the severity of the collision as detected by the MRS II control module.
6
Passive Safety Systems
BST ACTIVATION
Once activated, The ignitor generates a gas
charge which is directed down the internal
discharge tube.
This causes the tapered end of the B+ cable
contact to dislodge from its seated position
which immediately opens the circuit.
The force of the charge continues to push the
cable contact away from its seated contact. The
spring tabs of the housing are compressed as
the contact pushes to the end of its travel.
When the contact hits the end stop of the housing
it bounces back against the spring tabs causing
the contact to stop without returning to the seated
position.
7
Passive Safety Systems
Di
Mo
Diagnosis is possible with the MODIC or DIS tester,
the DIS allows symptom troubleshooting, test modules, and ETM coverage of the ITS and BST.
C
MRS II DIAGNOSIS AND SERVICES
PROCEDURES
Installation of a replacement MRS II Control Module
requires ZCS coding also using the DIS or MoDiC.
Typical with any airbag, it is to be
replaced as a unit after deployment.
This is the same for ITS assemblies
and the BST.
Follow the precautionary measures
outlined in the repair manual section
of TIS, and always disconnect the
battery prior to any repairs.
All airbag units including the ITS
assemblies are part number specific
by model. Always use the EPC to
verify the correct part number for
any system part prior to ordering.
Once a BST has been activated the
metal crimp of the B+ wire is pushed
out of the BST housing and exposed.
This provides a quick visual check of
it’s circuit status. A BST replacement
splice kit is available from parts, this
eliminates replacing the entire B+
ACTIVATED BST
(CRIMP EXPOSED)
cable. The splice kit comes complete
with instructions and wire cutting/striping measurements. Follow instructions completely to
prevent future voltage drop problems in this cruBST REPLACEMENT SPLICE KIT
cial circuit.
(CRIMP NOT EXPOSED)
8
Passive Safety Systems
Multiple Restraint System III (MRS)
Model: E46/2, E46/4, E46/3, E46 Convertible
Production Date: E46/4 from 9/99, all others from start of production.
Objectives
After completing this module you should be able to:
•
Understand the difference in airbag triggering logic over the previous MRS system.
•
Describe how the two different ignition stages of the front airbags are triggered to
create three different inflation speeds.
•
Explain the method used by the MRS for shutting off the fuel pump
9
Passive Safety Systems
MULTIPLE RESTRAINT SYSTEM (MRS III)
INTRODUCTION
The Multiple Restraint System (MRS III) employs the use of “SMART” technology. Smart
technology refers to the control module’s programming which allows for the deployment of
the airbags, in stages, depending on the severity of the impact. Two stage airbags are used
for both the driver and front passenger which allows for a softer cushioning effect when the
bags are triggered at lighter impacts.
The MRS III system is installed in E38/E39 and E46 Sedan vehicles as of 9/99 production
and in E46 Coupes as of 6/99 production.
MRS III control modules are manufactured by either Bosch or Temic. While the functional
operation of both modules are the same. The control modules are not interchangeable from
a replacement standpoint. Always refer to the EPC parts system to ensure that the proper
module is installed in the vehicle.
In addition to the use of two stage airbags for the driver and passenger, the following features are also included in the MRS III system:
•
The MRS III control module is linked to the K-Bus for coding and diagnosis.
•
The MRS III includes a fuel pump cut off feature in the event of an airbag deployment.
•
Inert gas generators are now used for all air bags and seat belt tensioners. (This
method is referred to as Cold Gas Inflation.)
•
The inert gas is a mixture of compressed Hydrogen (13.5%) and Oxygen (68.5%).
10
Passive Safety Systems
COMPONENTS
MRS III CONTROL MODULE
The control module is mounted in the center console area on the driveshaft tunnel below
the emergency brake handle.
The control module contains the processing electronics (Smart Technology) for triggering of
all air bags and pyrotechnic devices installed in the vehicle. Two electronic deceleration sensors are installed in the module for crash or impact detection.
11
Passive Safety Systems
SATELLITE SENSORS
The satellite sensors are mounted below the driver’s and passenger’s front seats on the
seat frame. The function of the sensors is to detect the severity of side impacts and signal
the MRS III control module, through a pulse modulated signal, in the event of a crash. The
control module uses this input signal along with its internal impact sensor signal to determine the deployment of the side/head airbags.
As with the control modules, the satellite sensors are
manufacturer specific. The Temic sensors have a
three wire connector which will not interchange with
the Bosch sensors. Only two of the wires are used for
the satellite sensor’s operation. The signal for deployment of the bags is carried over the power wire of the
sensor.
12
Passive Safety Systems
DRIVER’S FRONT AIRBAG
The driver’s front airbag is a two stage bag similar to the passenger’s front side bag. The
complete assembly is mounted beneath the cover in the center of the steering wheel as
with previous airbags. The assembly now contains the inert gas generator chamber and
two ignition stages (ignitors).
The airbag consists of:
• Accumulator/gas generator
• Two ignition capsules
• Propellant gas - 13.5% Hydrogen/86.5% Oxygen
13
Passive Safety Systems
PASSENGER’S FRONT AIRBAG
The passenger’s front airbag is similar to the unit installed on E38/E39 vehicles as of 9/98
production. The passenger’s airbag consists of:
•
•
•
Pressure accumulator/gas generator
Two ignition capsules - for two stage activation
Propellant gas of - 13.5% Hydrogen/86.5% Oxygen
PRESSURE ACCUMULATOR
IGNITION CAPSULES
14
Passive Safety Systems
SIDE AIRBAGS FRONT/REAR (THORAX)
The side airbags continue to be mounted behind the door panels on the front and rear
doors. Deployment of the side airbags is dependent on the triggering thresholds programmed in the MRS III control module, based on the inputs from the satellite sensors and
internal crash sensor.
The side airbags use the same inflation method as the driver’s and passenger’s front bags.
15
Passive Safety Systems
HEAD PROTECTION AIRBAG (ITS: Inflatable Tubular Structure)
The head protection airbags are similar to the ITS bags used on the MRS II system. They
continue to be mounted from the “A” pillar up along the headliner and are anchored behind
the “B” pillar. The ITS bags of the MRS III system are also the cold gas inflation type. On
MRS III systems and later, the passenger side (thorax) bag is not deployed if the passenger
seat is not detected as occupied.
16
Passive Safety Systems
BATTERY SAFETY TERMINAL (BST)
As with previous systems, the BST is used to disconnect the battery’s “B+” connection to
the engine compartment in the event of an airbag deployment. The safety measure helps
prevents the possibility of a short circuit causing a fire.
17
Passive Safety Systems
SEAT BELT TENSIONERS
The seat belt tensioners are a new design
and also make use of the inert gas for triggering. The MRS III control module will
deploy the seat belt tensioners based on
the programmed parameters during impact.
SEAT OCCUPANCY SENSOR (SBE)
The SBE continues to be used as an input to the MRS III control module for detection of a
front seat passenger. The module uses the input to determine seat belt tensioner and/or
front airbag deployment.
18
Passive Safety Systems
MRS III OPERATION
As with previous systems, the triggering thresholds are programmed in the MRS III control
module. These thresholds are determined by BMW through crash and vehicle testing during the design and development of the vehicle. These thresholds will vary depending on the
vehicle size and design.
There are several different thresholds for airbag and safety restraint deployment:
•
Belt pre-tensioner threshold for activation of the seat belt tensioners.
•
Airbag threshold #1 - the first level of activation for the two stage front airbags, always
deployed first when the front triggering threshold is reached.
•
Airbag threshold #2 - the second level of the two stage front airbags, can be deployed
simultaneously or after a time delay, depending on the severity of the impact.
•
Rear crash threshold - for activation of the seatbelt tensioners with a rear impact.
•
Battery safety terminal threshold - for activation of the BST with airbag deployment.
•
Side airbag/ITS threshold - for deployment of the side and thorax airbags.
19
Passive Safety Systems
MRS III OPERATION
TRIGGERING THRESHOLDS - TWO STAGE AIRBAGS
The programming of the MRS III includes four triggering thresholds for the two stage front
airbags. The triggering of the front airbags is also dependent on whether the seat belts are
connected and if the front passenger seat is occupied. The triggering thresholds for the
two stage airbags are as follows:
If the signal from the SBE is defective on triggering, the MRS III will deploy as if the seat is
occupied.
If the signal from the seat belt contacts are defective, the MRS III will deploy as if the belts
were not buckled.
20
Passive Safety Systems
MRS III I-P-O
MS 43.0
21
Passive Safety Systems
TRIGGERING THRESHOLDS
SIDE AIRBAGS/ITS
The triggering thresholds for the side airbags/ITS is dependent on the signals from the
satellite sensors and the crash sensor in the MRS III control module. The triggering thresholds are independent of the belt tensioners.
BELT TENSIONER
The triggering of the belt tensioners is dependent on the signal from the seat belt contact
and the severity of the impact as detected by the control module.
BATTERY SAFETY TERMINAL
The BST will deploy in a frontal impact at threshold 2 or greater. The threshold for BST activation with a side impact is programmed separately in the side deployment criteria. The
BST will also be deployed when the rear impact threshold is exceeded.
FUEL PUMP SHUT-DOWN
The MRS III system is linked via the K-Bus/CAN Bus to the Engine Control Module for
deactivation of the fuel pump. The MRS III will signal the DME over the K-Bus through the
instrument cluster and CAN Bus to shut off the fuel pump in the event that any crash
threshold is exceeded.
22
Passive Safety Systems
Workshop Hints
Diagnosis and troubleshooting of the MRS III system is fault driven and can be accessed
using the DISplus or MoDiC. The control module performs a self test of the system every
time the ignition is switched on ( this includes the satellite sensors and seat occupancy sensor). Any faults with the system will cause the warning lamp in the instrument cluster to
remain illuminated after the engine is started.
Installation of a new or replacement control module requires ZCS coding also using the DIS
plus or MoDiC.
When servicing or replacing any MRS III components, always follow precautionary measures outlined in the repair manual of TIS. this includes disconnecting the battery prior to
any repair or maintenance work being performed.
All airbag components are part number specific by model and require verification in the
EPC to ensure the correct component is being installed.
23
Passive Safety Systems
Roll Over Protection System
Model: E46 Convertible
Production Date: 01/00
Objectives
After completing this module, you should be able to:
•
Identify all components of the Roll Over Protection System.
•
Describe the operation of the Clinometer sensor to deploy the Roll Over bars.
•
Describe the operation of the “G” sensor to deploy the Roll Over bars.
•
Perform the resetting procedure for the RPS after deployment.
24
Passive Safety Systems
Purpose of the System
The roll over protection system (RPS) is a passive safety system that is designed to deploy
only if the vehicle is in danger of rolling over, to afford vehicle occupants additional protection. In addition to the reinforcing tube integrated in the windshield frame, RPS ensures that
all the rear passengers are provided with necessary head clearance should the car roll over.
ART-HRRBUP
ART-HEADREST
ART-HRRBUP1
The system is similar to the roll over protection system used on the E36iC. The electronic
control module for roll over detection and deployment remains the same as on the E36iC.
However, the system has been redesigned in terms of function, solidity and safety.
25
Passive Safety Systems
Components of the System:
Roll Over Bar Cassettes
The roll over cassettes are new and constructed completely from aluminum with a pad integrated in the top of the bar. The cassettes are bolted into the reinforced carrier behind the
seat back. When retracted, they are covered by the rear head rest which incorporate a flap,
at the back, that will open when the roll bars deploy.
Reset Lever
ART-KT5452
A new resetting procedure is incorporated to retract
the bar after deployment. The reset is constructed in
the roll bar cassette and the separate tool has been
eliminated.
ART-KT5450
Pulling the reset lever forward will release the ratchet
assembly so that the roll bar can be pushed down and
locked into the solenoids.
ART-KT5451
26
Passive Safety Systems
Roll Over Bar Cassettes
A newly designed solenoid, mounted in the bottom of the cassette, holds the bars in the
retracted position until triggered by the roll over sensor for deployment.
ART-KT5449
27
Passive Safety Systems
Roll Over Sensor
The rollover sensor is installed in the rear behind the right rear seat back on the rollover cassette. It contains the processing electronics for rollover detection and deployment final
stage for triggering the rollover bar solenoids. Two capacitors are also installed for roll bar
deployment in the event of a power failure with the system during an a crash. The sensor
is connected to the diagnostic link for troubleshooting purposes.
The sensor preforms a self check every time the ignition is switched on. If any faults are
detected, the warning lamp in the cluster will illuminate. If possible, the system will trigger
the solenoids even though a fault is stored in the fault memory.
ART-ROLLOVERSENSOR
ART-ROLLOVERSEN1
28
Passive Safety Systems
Clinometer
The clinometer inside the sensor consists of three level floats to detect body tilting, transverse and longitudinal acceleration for roll bar deployment. two floats are positioned on
opposing angles of 52 degrees to the horizontal axis of the vehicle. The third float is positioned at an angle of 72 degrees to the longitudinal axis. LED transmitters and phototransistor receivers are positioned to read the air bubble float as it moves in the glass tube.
ART-CLINOMETER
If the vehicle starts to roll over sideways or end-to-end, beyond the critical angles, the air
bubble will move and interrupt the LED signal. The electronics of the sensor will then trigger the solenoids and the roll bars will deploy.
29
Passive Safety Systems
“G” Sensor
The “G” sensor is used to trigger the roll bars if the vehicle should become airborne. the “G”
sensor consists of a reed contact, magnet and spring assembly. As long as the vehicle is
in contact with the road surface, the spring does not have enough tension to overcome the
weight of the magnet and gravity.
E46ICGSENSOR
However, if the vehicle becomes airborne and weightlessness occurs, the spring will force
the magnet up and the reed contact will open. This will signal the electronics of the sensor
to trigger the solenoids and the roll bar will deploy.
A time period of approximately .3 seconds with a “G” force of approximately 0.9 or less is
required before the bars will deploy.
ART-E46ICGSENSORB
30
Passive Safety Systems
Roll Over Sensor Diagnosis and Testing
The sensor performs a self check every time the ignition key is switched on. All components
of the sensor are checked including the output stages for roll bar triggering. If a fault is
detected, the warning lamp in the cluster is illuminated and the fault is stored in the memory of the RPS Sensor.
In the event of a power failure, capacitors in the sensor can still trigger the solenoids for
approximately 5 seconds.
ROLL OVER SENSOR I - P - O
ART-E46ICRPSDIAG1
31
Passive Safety Systems
Review Questions
1. What is the relationship between the Head Protection System and the side airbags?
2. What type of signal does the MRS control unit receive from the Satellite sensors? How
does this signal change to indicate an impact?
3. How many sensors must detect an impact before a side airbag will deploy?
4. Describe the systems or components that are still operational after the BST has
deployed.
5. What is meant by the term “Smart Airbag”?
6. What change was made to the wiring of the satellite sensors between MRS II and III?
7. Describe “cold gas inflation”.
8. What are the critical angles for RPS to deploy?
9. What is the purpose of the “G” sensor in the RPS system?
10. Describe the resetting procedure for the E46 RPS cassette after deployment. At what
intervals should the RPS be tested?
32
Passive Safety Systems
Table of Contents
E46 CLIMATE CONTROL
Subject
Page
E46 IHKA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Control Panel. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Fresh Air Micro Filter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Temperature Regulation - Heating. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Temperature Regulation - Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Compressor Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Stepper Motor M-Bus Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Convertible Rear Window Defroster. . . . . . . . . . . . . . . . . . . . . . . . . . 10
IHKA Personalization. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
System Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
Diagnosis and Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
E46 IHKA I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Solar Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Purpose of the System.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16
Solar Radiation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Solar Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
System Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Initial Print Date:10/30/00
Revision Date:12/05/00
Subject
Page
Control Curves
Blower Intervention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Temperature Intervention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Ventilation Intervention. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
E46 IHKR. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
System Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
IHKR I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
IHKR Control Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
IHKR Housing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Principle of operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Blower adjustment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
Air Distribution. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Temperature Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Engine Map Cooling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Service Station Feature. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Air Conditioning Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Air Intake. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Ram Effect Air Compensation. . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Rear Window Defroster. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
E46 IHKA
Model: E46
Production Date: From 6/98
Objectives
After completing this module you should be able to:
•
Know how to replace the Fresh Air Micro Filter.
•
Describe the climate control functions performed by the IHKA control unit.
•
Explain the compressor activation circuit.
•
Recognize Car and Key Memory programming possibilities.
3
E46 Climate Control
E46 IHKA Climate Control
The IHKA heater/air conditioner in the E46 is similar to the system previously installed in the
E36. Design and component changes were made to improve the overall performance and
operation of the system. This module will deal with the changes and highlights of the E46
IHKA system. Features of the IHKA system include:
•
•
•
•
•
•
•
Control Panel/Module
Single heater core for temperature regulation
M-Bus Control of all stepper motors
Fresh air micro filter
Regulated A/C compressor
Regulated auxiliary fan operation
Heater Control Personalization
A
CONTROL PANEL
All heating and air conditioning functions are carried out at the control panel. The panel is
constructed as follows:
• The three manual air distribution buttons are located on the left side of the panel for
upface vent and footwell distribution.
• The automatic air distribution button is located on the bottom of the panel along with
the temperature control - blower speed control and recirculation control buttons.
• The defrost, air conditions request and rear window defogger buttons are located on
the right side of the panel.
• The LCD matrix displays the requested temperature setting and blower speeds as on
the previous system. There is now only one setting for temperature control.
• The interior temperature sensor and blower fan are located on the left side of the LCD
matrix.
4
E46 Climate Control
FRESH AIR MICRO FILTER
The fresh air micro filter is installed in the fresh air inlet of the engine compartment. The filter can be serviced quickly by removing the plastic cover and removing the filter.
5
E46 Climate Control
TEMPERATURE REGULATION-HEATING
The E46 uses one water valve/heater core as part of interior temperature regulation. The
water valve is pulsed to control the flow of coolant through the heater core as on other systems.
Temperature regulation is based on the inputs from:
•
•
•
•
•
•
Temperature control switch
Interior temperature sensor
Ambient temperature signal
Heater core sensor
Evaporator temperature signal
"Y" factor
The rocker switch is used to select the desired cabin temperature which is displayed in the
matrix of the control panel. The range for temperature display is from 60 to 90 ° F.
SERVICE STATION FEATURE - The "Service Station" feature introduced with the E38 IHKA
is integrated into the E46 IHKA. This prevents the heater core from being flooded with hot
coolant when refueling the vehicle.
6
E46 Climate Control
TEMPERATURE REGULATION - COOLING
Air conditioning control on the E46 is similar to the E39 IHKA system. The system uses the
variable displacement compressor. The swash plate of the compressor is hinged so that is
can vary the piston travel based on the output requirements of the system.
AUX. FAN
MS42.0
COMPRESSOR
A
EVAPORATOR
PRESSURE
SENSOR
7
E46 Climate Control
COMPRESSOR CONTROL
Control of the A/C compressor is a function of the Engine Control Module as in the E36.
However, the control has changed to include the regulated auxiliary fan operation.
Pressing the snowflake button is a request for A/C activation. As long as the evaporator
temperature is Above 36° F, the IHKA will signal the DME control module to activate the
compressor.
The IHKA control module sends the following signals to the DME over the K-Bus and CAN
Bus via the instrument cluster:
• Request for A/C activation (signal KO)
• Load torque for switching the compressor on
• Requested auxiliary fan speed
The IHKA determines the load torque for compressor activation and required auxiliary fan
speed from the pressure sensor mounted on the receiver/dryer.
The pressure sensor provides a linear voltage input signal (0 - 5 volts) to the IHKA control
module. The IHKA processes this signal and determines the load torque of the system (0
to 30 Nm with a variable displacement compressor). The higher the pressure in the system,
the higher the voltage input signal to the IHKA.
The output signal to the DME will enable the engine control module to modify the idle
speed, timing and fuel injection amount based on the load that will be imposed when the
compressor is activated.
The auxiliary fan is now a variable speed fan (15 stages) based on the system load. The
DME will activate the fan through a pulse modulated final stage control.
8
E46 Climate Control
STEPPER MOTOR M-BUS CONTROL
The E46 uses the M-Bus for stepper motor control. All five stepper motors of the IHKA
are bus controlled including:
•
•
•
•
Two fresh air/recirc-air flap motors
Face vent flap motor
Footwell flap motor
Defrost flap motor
Due to the requirement for a fast acting motor for the fresh/recirc flaps, two different stepper motors (slow/fast) are used in the system.
9
E46 Climate Control
CONVERTIBLE REAR WINDOW DEFROSTER
Purpose of the System:
A two relay system was designed for the E46iC that supplies power to either rear window
defogger grid. The two relay system will also communicates with the audio system amplifier to change the dynamics of the sound for either top up/hard top installed or top down
driving
Components of the System:
Two relays, located on the right side rear quarter panel behind the interior trim cover, are
used for rear defroster operation.
•
Relay K-13 receives KL 30 and the activa
tion signal from the IHKA control module.
The output from the relay will switch the
rear defroster ON if the hard top is installed.
•
Relay K-99 receives KL 30 from relay K-13
and it supplies the rear defogger grid in the
soft top glass window when the top is
raised.
10
E46 Climate Control
System Operation
The rear defroster operation is a function of the IHKA system, with the control module
responsible for switching the system ON/OFF. Two rear defrosted grids are used, one
installed in the soft top rear glass and the other in the optional hard top rear glass.
When the button is pressed on the IHKA control panel, Relay K-13 is energized. If the hard
top is installed, power is supplied to the grid through the connector strip on the hard top
lock.
CVM
Top Closed and
locked to frame.
12V
30
30
15
Open and
unlocked.
0V
Audio
Amp.
K-13
Rear window
defogger relay
(for hard top).
To hard top rear
window contact.
IHKA
Control Unit
K-99
Rear window
defogger relay.
31
Rear window
defroster grid
KL 31
61E46DEFROSTER0200
Relay K-13 also supplies KL 30 to relay K-99 when the button is pressed on the IHKA control panel. Relay K-99 is energized when KL R is switched ON and the soft top is closed
and locked to the windshield frame. This allows the grid in the soft top window to be heated. When the soft top is lowered, KL R to relay K-99 is interrupted by the CVM to prevent
the grid from heating when the top is lowered into the storage compartment.
11
E46 Climate Control
IHKA PERSONALIZATION
The features of Car/Key Memory allow various functions/features of the IHKA control to be
tailored to the individual owner's/driver's wishes.
The functions of the IHKA that can be programmed to the owner's/driver's wishes include:
•
•
•
•
•
•
•
•
Automatic activation of recirc when the vehicle is started
Adjustment (raising/lowering) of the blower speed
Automatic opening of the ventilation flaps with warm coolant
Automatic closing of the footwell flap with A/C activation
Automatic closing of the defroster flaps with A/C activation
Correction of the set temperature (raise/lower)
Automatic activation of the compressor control when the ignition is switched on
Auto program for the blower control when the ignition is switched on
These features are programmed using the coding/programming function of the DIS/MoDiC.
Units Display Change
80
100
D-BUS
0
20
2
120 140
160
180
80
60
4
5
1/min
x1000
120
6
1
200
40
11
3
100
60
40
12
220
240
20
140
UNLEADED GASOLINE ONLY
km/h
0
50 30 20 15
7
12
MPH
20 PIN
DIAGNOSTIC
CONNECTION
DiC
• Recirc
Air Memory
Mo
DIS
A
MoDiC
12
E46 Climate Control
IHKA
SYSTEM OPERATION
The balance of the E46 IHKA system's features and operation carry over from the E36
including:
•
•
•
•
•
•
•
Maximum defrost operation
Rear window defogger operation
Final stage blower control
Road speed dependent fresh air flap operation
Air distribution control
Stepper motor calibration run
Cold start interlock
DIAGNOSIS AND TROUBLESHOOTING
The "self diagnostics" of the IHKA control module monitors the status of inputs and outputs
of the system. If a fault is detected, it is initially entered in RAM and than in the EEPROM
when the ignition is switched off. If available, a replacement value will be activated when
various sensor faults are detected as with previous systems. A maximum of six faults can
be stored in the EEPROM when the ignition is switched off.
The E46 IHKA is connected to the diagnostic link via the K -Bus/instrument cluster. The
system uses the E46 "Fault Symptom Troubleshooting " procedures for troubleshooting
problems and faults with the system.
When troubleshooting problems with the E46 IHKA, it is important to note that because the
Car/Key Memory feature can change the functionality of the system, a review of the setting should be performed prior to condemning a component as faulty.
13
E46 Climate Control
E46 IHKA I.P.O
As introduced.
14
E46 Climate Control
SOLAR SENSOR
Model: E38, E39, E46
Production Date: E38 3/99, E46 9/99, E39 9/00
Objectives
After completing this module you should be able to:
•
Describe the operation of the solar sensor as it applies to the IHKA systems.
•
List the output functions effected by the solar sensor input.
•
Describe how the solar sensor affects the various output functions.
15
E46 Climate Control
Purpose of the System:
The purpose of the solar sensor is to compensate the climate control system’s output for
the radiant heating effect of the sun. This will aid the IHKA in maintaining a constant comfort level, in the vehicle’s interior, during all driving conditions.
The function of heating and air conditioning systems in BMW vehicles is to provide the driver and passengers a comfortable atmosphere regardless of conditions outside of the vehicle. Based on the temperature signal inputs, blower setting, flaps portioning, program settings in the control module and influencing variables, the IHKA control module is able to
process these inputs to achieve the desired comfort level.
The following input variables are
processed by the IHKA module:
•
•
•
•
•
•
•
Interior temperature
Heat exchanger temperature
Ventilation temperature (E38)
Evaporator temperature
Air volume setting
Engine temperature and RPM
Exterior temperature
The processed variable “Y-factor” is determined by using the above inputs. The Y-factor
then represents how much adjustment is necessary by the IHKA module to achieve the set
temperature.
16
E46 Climate Control
Solar Radiation
Solar radiation, from the sun, passes through the earths atmosphere in the form of light
(both visible and non-visible) and heat (sunshine). To date, the influence of solar radiation
on the climate control system in the vehicle has only been compensated for by an average
value stored in the control module and based on control settings and outside temperature
values.
Solar Sensor
The solar sensor can detect the amount of solar radiation that is influencing the temperature and climate in the vehicles interior. The IHKA control module monitors the input from
the solar sensor and adds the value to its processing factors. The settings of the climate
control system are changed to compensate for this additional influence.
The settings of the following IHKA components are adjusted to compensate for changes
in solar radiation:
• Blower - The blower curve is changed
• Stratification (mixing flaps) - The stratification outlet air temperature is changed (not E46)
• Ventilation - The opening angles of the ventilation flaps are changed.
17
E46 Climate Control
Components:
In the E38, The solar sensor is integrated in the housing of the anti-theft warning system
LED. The warning indicator LED is installed on the outlet grille in the top center of the
instrument panel where solar radiation can directly reach the solar sensor.
The DWA LED with solar sensor is an additional wiring harness with a 4-pin plug connector.
DWA LED with integrated solar sensor
1
DWA LED plug connector
DWA LED/SOLAR
SENSOR MODULE
2
4-pin solar 3sensor plug connector
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
18
E46 Climate Control
The solar sensor consists of two photoresistors, which are integrated on the left and right
sides of the DWA housing next to the DWA LED. The photoresistors sense the different
intensity levels of the solar radiation.
2
1
3
4
DWA LED dismantled; housing and pc-board with LED and solar sensor housing
1 The photoresistor on the right is fitted under
the plastic cover
2 The photoresistor on the left is fitted under the
plastic cover
3 PC-board, DWA LED and solar sensor
4 DWA LED housing
SOLAR SENSOR
The E46 solar sensor is located in the right
defroster outlet at the base of the windshield.
The E46 sensor contains one photoresistor for
sensing solar radiation.
19
E46 Climate Control
System Operation
The solar sensor receives power (5 volts) and ground from the IHKA control module. The
module then reads the voltage drop across the photoresistor and determines the degree of
solar heating based on the change in voltage. The voltage drop across the photoresistor
increases as solar radiation increases. The IHKA control module monitoring voltage will
decrease indicating an increase in solar heating. The module processes the input every 10
seconds and checks it for plausibility based on a limit value monitoring function.
Values outside the limit indicate a malfunction and the signal from the sensor is ignored by
the module.
As solar radiation levels increase, the control curves, stored in the IHKA module, for the
blower fan, mixing flaps and ventilation (face vent) flaps are shifted to compensate for the
additional heat.
The solar sensor inputs to the IHKA control module can influence the settings on the relevant side (driver/front passenger) on the E38 and E39. No separate regulation is possible
on the E46.
When driving at night, during cloudy periods or through tunnels, the control maps are shifted back to their base settings.
20
E46 Climate Control
CONTROL CURVES OPERATION
Blower Intervention
The graph below illustrates the solar influence on the blower fan with a constant Y factor
and the solar influence changing from 0 th 100%.
Blower power curves
The middle curve illustrates a blower curve without any solar influence. At a constant Y factor of 20%, the solar influence on the IHKA control module will cause the blower curve to
shift as the radiation increases from 0 to 100%.
With a solar influence of 0%, curve “B” is used, providing 25% power to the blower.
As the solar influence increases, the curve shifts upward until the solar influence reaches
100%. At this point, curve “A” is used providing 36% power to the blower.
During heating, the blower power decreases as solar influence increases.
While cooling, the blower power will increase as solar influence increases.
21
E46 Climate Control
Stratification (Temperature Intervention) E38 only
The mixing flaps will open less in the direction of heat for blending air as the solar influence
increases. The graph below represents the influence of the solar sensor on the stratification
flap settings
To illustrate the influence of the solar sensor on the mixing flap position, the Y factor remains
constant at 20%.
With a solar influence of 0% curve “A” is adopted for the various outside temperatures. As
the outside temperature decreases, the mixing flap is moved toward the warmer setting
blending more heat.
With a solar influence of 100% curve “B” is adopted for the various outside temperatures.
As the outside temperature decreases, the mixing flap is still moved toward the warmer setting but it does not move as far. The solar influence is compensating to provide the same
comfort level.
With the mixing flap thumbwheel at 100 or 0% (full hot or cold), the flaps are in the default
position and there will be no solar influence.
The left and right mixing flaps are controlled independently based on the individual settings
and left and right solar sensor inputs.
22
E46 Climate Control
Ventilation Intervention (Center Vent Air Distribution)
The influence of the solar sensor on the ventilation flaps is shown in the graph below.
The normal curve “B” applies when there is no solar sensor influence 0%, or if the sensor
is defective.
The maximum curve “A” applies when the solar influence is 100%.
The ventilation flaps will close less as the solar influence increases. This allows more cool
air from the center vents as the solar radiation increases.
This adjustment is also independently adjustable on the E38 based on the left/right solar
sensor inputs.
23
E46 Climate Control
DIAGNOSIS
Troubleshooting of the solar sensor (left/right) is carried out through the IHKA diagnostic
program using the DIS or MoDiC.
Status displays for the solar sensor input are available in percentages. The status displays
can be checked while applying a light or heat source to the solar sensor to view the change
in value.
The E46 diagnostic program for the IHKA
system contains a test module B645000011 for testing the operation of the solar
sensor.
The IHKA control module monitors the solar sensor and will set a fault code for:
• Shorts to B+ or ground
• Open circuits
The IHKA control module will function as a system without solar influence correction if the
sensor is defective.
Recognition of the solar sensor and its influencing capabilities is enabled via ZCS coding.
Remember to adopt the code whenever possible to avoid loosing car/key memory function
changes. Also the IHKA control module must be disconnected from B+ before coding can
become permanent.
24
E46 Climate Control
Workshop Hints
E38 vehicles
To remove the solar sensor from an E38, refer to TIS - RM 6422161, removal of the center
outlet grille at the top of the dash. After removal of the grille, disconnect the plug connector of the DWA indicator and solar sensor and pull the sensor from the grille.
E46 vehicles
Removal of the E46 solar sensor requires removal of the instrument panel. However, for
testing purposes, the connector is located in-line, attached to the harness for connector
X610.
X18786
in-line connector
for Solar Sensor.
25
E46 Climate Control
E46 IHKR
Model: E46 (325i/it/Ci/Cic, M3)
Production Date: From 9/00
Objectives
After completing this module you should be able to:
•
Recognize the climate control functions performed by the IHKR system.
•
Identify the changes compared to the E46 IHKA system.
•
Understand the method of temperature control used by the IHKR.
•
Describe how the A/C compressor is controlled.
26
E46 Climate Control
Purpose of the system
Beginning M.Y. 2001, the 325i/it/Ci/Cic and M3 are fitted with IHKR as standard
equipment. The IHKA system is available as an option on these models.
IHKR is a semi-automatically regulated heating
and air-conditioning system, similar to the
IHKR introduced for the 2001 E39 and E53.
The purpose of the system is to allow the
vehicle occupants to select the desired
temperature, air outlet distribution and volume
manually.
The system then automatically regulates the
temperature of the cabin based on the manual settings.
The functions provided by the E46 IHKR are:
•
Control of the blower.
•
Air distribution control.
•
Stratification flap controlled by a bowden cable
•
Temperature Control
•
Service Station feature
•
Air conditioning request to DME
•
Recirculation air
•
Ram effect air compensation
•
Rear window defroster
27
E46 Climate Control
System Components
The E46 IHKR consists of the following components:
•
IHKR control unit with operating controls
•
IHKR integrated heater and air conditioning case
•
Heater core temperature sensor
•
Evaporator temperature sensor
•
Refrigerant circuit pressure sensor
•
Double cage blower motor and final stage
•
Water valve
•
Air distribution micro-switch
•
M-bus with 3 smart stepper motors:
- Air distribution
- Fresh air/re-circulation left (high speed motor)
- Fresh air/re-circulation right (high speed motor)
•
Compressor relay (DME controlled)
•
Auxiliary fan (DME controlled)
•
Rear window defroster relay
•
K-bus interface
The following signals are transmitted and received over the K-bus:
- Vehicle speed
- Engine speed
- Coolant temperature
- Outside temperature
- Terminal 15, 61, 50,58G (panel lighting)
- Compressor load
- Diagnosis and coding
- Compressor request
•
Fresh air Micro-filter
28
E46 Climate Control
E46 IHKR I.P.O
BLOWER MOTOR OUTPUT STAGE
KL31
+
KL30
M
+
-
KL15
0
1
2
3
4
FAN SPEED
WATER VALVE
KL30
A/C REQUEST
M-BUS
- FRESH AIR/RECIRC LEFT
RE-CIRCULATION
REAR DEFROST
TEMPERATURE
CONTROL
- FRESH AIR/RECIRC RIGHT
- AIR DISTRIBUTION
E46
IHKR
REAR WINDOW DEFROST RELAY
KL 15 KL 30
AIR DISTRIBUTION
POTENTIOMETER
EVAPORATOR
TEMPERATURE
COMPRESSOR CONTROL
KL30
KO REL
REFRIGERANT PRESSURE
DME
KL30
AIR DISTRIBUTION
MICRO-SWITCH
M
AUXILIARY FAN CONTROL
HEATER CORE
TEMPERATURE
DSC III
kjhsdfkhsdflkhsdlkfjhlkjghkg
lkdkfljdflkjdsfljdslfjldskjflkjdflk
ldsflsdfklhdsfhsdfhsdkhfkhsdf
kldjfkljdfkjdskfkjdskfjkljdfkldsfk
kjsdfkljsdfkdsfkjdsfkljsdfkjds
ldjsfklkjsdfkldsjfkdsjfkdsfkdfklk
K-BUS
BMW DIS
DIS
BMW
BMW DIS
LSZ
PANEL
ILLUMINATION 58G
29
E46 Climate Control
IHKR control unit with operating controls
The IHKR control unit is incorporated into the control panel. The control panel consists of
three buttons and three rotary dials. The control unit communicates over the K bus.
1.
2.
3.
4.
Blower control potentiometer
Recirculation button
Temperature control potentiometer
Air distribution potentiometer
1
2
3
5
6
5. Air conditioning request button
6. Rear window defroster button
X608
6 pin
X610
18 pin
4
X613
3 pin M-bus
X18341
6 pin
IHKR Case
The E46 IHKR case is similar in design to the E46 IHKA heating and A/C case.
1. Heater Core Temp.
Sensor
2. Heater core
3. Evaporator Temp
Sensor
4. Evaporator
5. Double Cage Blower
30
E46 Climate Control
Principle of operation
Blower adjustment
The blower rotary dial potentiometer has four settings. Each progressive step represents a
25% increase in blower volume. The control unit determines the desired blower setting by
the signal from the potentiometer and then sends a voltage signal to the final stage unit.
The voltage signal to the final stage unit ranges from 1.8V to a maximum of 7.1V (Normal
blower power in Key Memory).
The final stage unit then regulates blower motor voltage to control the blower volume.
There is no automatic influence on the blower setting.
The blower control potentiometer is the master on/off switch for the IHKR system. The
water valve is closed (energized) in the blower zero (off) position. The LEDs for re-circulated air and air conditioning are switched off and the compressor is switched off. The rear
defroster operation is not affected by the system being switched off.
Air distribution
The selection of air distribution is carried out using the rotary dial potentiometer (42 steps).
Each step of the potentiometer represents a percentage. The percentage indicates the
desired air distribution setting.
FULL
DEFROST
BLEND
OF BLEND
FULL
FOOTWELL
0
90
BLEND
OF BLEND
8
82
16
74
24
66
33
57
49
41
FULL
VENT
Movement of the stratification flap for face ventilation is carried out by rotating a thumb wheel
between the face vent discharge nozzles. The
thumb wheel is connected to a bowden cable
that moves the flap.
The air distribution for defrost, ventilation and
footwell is performed by a single air distribution
stepper motor that is connected to the M-bus
and controlled by the IHKR control unit.
BLEND
OF BOTH
31
E46 Climate Control
The stepper motor drives a cam/lever assembly (1) that articulates all three air distribution
flaps. The position of the cam is confirmed by the air distribution micro-switch (2).
The air distribution micro-switch is provided
5V by the IHKR control unit. The micro
switch is closed by the rotating cam lobe in
two positions:
•
•
Full defrost 97% to 0%
Mixed face vent/footwell 37%
(quick confirmation)
When the switch is closed the signal at the
control unit goes low, informing the control
unit that it has reached that particular
position. The display in diagnosis recognizes this position as “off”.
Located on the right side of the IHKR case
A reference run is initiated the first time KL30 is switched on to the IHKR control unit. The
reference run is required to determine the position of the cam disc. The cam disc is
rotated until the micro-switch sends a signal to the control unit. After the reference run is
completed, the control unit recognizes what position the cam disc is in and thus the
position of all three air distribution flaps.
If the air distribution micro-switch is not able to produce a signal at the correct position, the
control unit will continue to operate the stepper motor at an estimated position. Eventually
the air distribution setting will not match the actual output. The air distribution micro-switch
circuit is fault monitored.
Temperature control
The desired interior temperature is set with the rotary dial potentiometer (34 steps). The
face of the dial itself has no marked temperatures, just a blue, white and red line that represents a comfort zone.
All of the air flowing into the IHKR housing must pass through the evaporator first before
being re-heated by the heater core. This is the principle used by all IHKR and IHKA systems.
The IHKR maintains the temperature of the discharge air by cycling the water valve to regulate the temperature of the heater core. The duty cycle applied to the water valve is based
on the “Y-factor” (correcting variable) and other variables.
32
E46 Climate Control
The Y-factor of the E46 IHKR is determined by:
•
•
•
Setting of the temperature control dial
Outside temperature (from Kombi via the K-bus)
Heater core temperature
Automatic temperature control is switched off when the temperature control dial is turned
all the way to the left (blue: water valve closed) or right (red: water valve full open) stop.
Each step of the potentiometer represents a temperature from max. cold (10oC) to max.
warm (49.5oC). This temperature value is combined with the outside temperature to form
a calculated set-point. The E46 IHKR does not use an interior temperature sensor.
The Y-factor is then determined by comparing the calculated set-point to the actual value
of the heater core sensor which is in the stream of air to the outlet ducts.
In addition to the Y-factor, the control unit evaluates coolant temperature and engine RPM
to determine water valve opening time. The valve opening times are:
• 0 ms at max. COLD
• 3600 ms at max. WARM
Engine map cooling
Map cooling is used by the DME MS 43.0 for the M54 engines. This can create very high
coolant temperatures which could be damaging to the climate control system. If the heater
core temperature exceeds 80oC, the water valve is closed until the temperature drops
below 80oC.
If the temperature at the heater core increases above 93oC (i.e. water valve faulty), the IHKR
will signal the DME (via K-bus/Kombi/CAN) to energized the map cooling thermostat.
Service Station Feature
The service station feature prevents the vehicle occupants from getting a blast of hot air
after the vehicle is restarted following a short stop. The water valve is powered closed by
the IHKR control unit for three minutes after shut-off. This prevents the heater core from
being flooded with hot coolant.
33
E46 Climate Control
Air Conditioning control
The air conditioning system is switched on by pressing the snow flake button and having
the blower dial on position 1 or greater. The LED in the button signals that the A/C is in
stand-by.
The IHKR control module sends the following signals to the DME over the K-bus-KombiCAN -bus connection:
•
•
•
•
IHKR on stand-by (signal AC)
Request for A/C activation (signal KO)
Calculated compressor load
Request for auxiliary fan
The IHKR determines the load torque for compressor activation and required auxiliary fan
speed from the pressure sensor mounted on the high side line next to the receiver dryer.
The refrigerant pressure sensor provides a voltage input signal (0-5 volts) to the IHKR. The
voltage value increases as pressure in the high side refrigerant circuit increases. The IHKR
processes this signal to determine the calculated load that will be placed on the engine
when the compressor is switched on. Pressure values that are too high or too low will
cause the compressor to be switched off.
Once all of the criteria for compressor operation have been met, the DME control module
will activate the compressor relay to energize the compressor magnetic clutch.
Control of the evaporator temperature is carried out by the IHKR signalling the DME to shut
off the compressor when the evaporator reaches the freezing point.
80
60
40
12
11
0
UNLEADED GASOLINE ONLY
80
120 140
100
160
180
60
2
120
220
240
20
140
5
1/min
x1000
6
0
km/h
MPH
4
1
200
40
20
3
100
5030 20 15
12
!
BRAKE
miles
SERVICE
ENGINE
SOON
0
1
ABS
EML
CAN-Bus
K-Bus: Signal AC/KO
IHKR
KOMBI
7
The IHKR cycles the compressor
at 1oC if the outside temperature
is above 68oF. The compressor
is cycled at 3oC if the outside
temperature is below 68oF.
2
3
4
DME
KL30
Evaporator Temp.
Refrigerant
Pressure
OUTPUT
STAGE
Auxiliary
Fan
34
E46 Climate Control
K19 relay
Compressor
M
Air Intake
The fresh air/re-circulation flaps are controlled
by a separate stepper motor for the left and
right side.
Fresh air flaps
The stepper motors are controlled by the Mbus and are located on the left and right sides
of the housing inside the passenger compartment.
The fresh air flaps are closed and the re-circ
doors are opened when the re-circ. button is
pressed with the system switched on.
When the key is turned off with re-circulation on, the fresh air flaps will open. Re-circulation memory in the IHKR control unit is 15 minutes. If the vehicle is started within 15 minutes the re-circulation setting will be restored.
If the system is shut off with the blower switch, the re-circulation function will have to be reenabled.
Ram effect air compensation
Similar to IHKA, when the fresh air flaps are open their position is affected by vehicle road
speed. This is to prevent an increase in air volume to the cabin with increasing vehicle
speed.
The IHKR receives the vehicle speed input every 2 seconds over the K-bus from the Kombi.
At a speed of 36mph the fresh air flaps will close progressively until the vehicle reaches
96mph, at which time the opening of the flaps will be 20%.
OPENING ANGLE OF
FRESH AIR FLAPS
100 %
0
60 %
40 % 30 % 20 % -
36 62
96
ROAD SPEED (MPH)
35
E46 Climate Control
Rear window defroster operation (All models)
The rear window defroster is controlled via a request from the button on the panel. After
switching on for the first time, the rear window is heated for 17 minutes. Output voltage to
the window is provided by the K13 rear defogger relay.
After automatic switch off, if the button is pressed once again the control unit will provide
another 17 minutes of operation. If the vehicle voltage drops below 11.4V during this second heating operation the function is stopped, however the LED on the button will not be
extinguished. If voltage increases past 12.2V for at least one second, operation will
resume. The control circuit of the convertible varies slightly due to the folding top.
Defroster operation specific to Convertibles
CVM
Top closed and
locked = 12V
30
30
15
K13
Rear window
defogger relay
K99
Rear defogger
relay
IHKR
Control unit
31
Rear window
defroster
When the button is pressed on the IHKR control panel, relay K13 is energized. K13 supplies KL 30 to defroster relay K99. Relay K99 is energized when the KLR is switched on
and the soft top is closed and locked to the windshield frame. This completes the circuit
and allows the rear window to be heated.
If the soft top is lowered during defroster operation, voltage to relay K99 is interrupted by
the CVM to prevent the rear window grid from heating when the top is lowered into the storage compartment.
36
E46 Climate Control
Workshop Hints
Diagnosis
Diagnosis of the E46 IHKR system is carried out using the DISplus or MoDiC. The IHKR is
connected to the diagnostic bus via the K-bus/Kombi connection. The system uses the
E46 test module driven diagnostic concept for troubleshooting faults with the system.
Service Functions:
Provides access to specialized test modules used as
post repair procedures. To
enter:
• Function selection
• Service Functions
• Body
• Heater- A/C control
Control Unit Functions:
Expert mode diagnosis available at
any time during troubleshooting. To
enter: press the Control Unit
Functions button at the lower right
corner of the screen.
The contents are:
• Identification
• Clear Fault Memory
• Read Fault Memory
• Component Activation
• Status Requests
Deactivate transport-lock
function
DSC III
kjhsdfkhsdflkhsdlkfjhlkjghkg
lkdkfljdflkjdsfljdslfjldskjflkjdflk
ldsflsdfklhdsfhsdfhsdkhfkhsdf
kldjfkljdfkjdskfkjdskfjkljdfkldsfk
kjsdfkljsdfkdsfkjdsfkljsdfkjds
ldjsfklkjsdfkldsjfkdsjfkdsfkdfklk
DIS
BMW DIS
BMW DIS
BM W
Test Modules: Faults with the E46 IHKR can be diagnosed using fault or symptom driven test
modules. To begin diagnosis:
• Perform the Short Test
• Select a vehicle symptom from the Symptom Selection page
• Select a test module from the Test Plan page
• Press the Test Schedule button
Test module are written in the E46 Diagnostic Concept.
37
E46 Climate Control
Coding
Coding must be performed if the IHKR control unit is replaced. ZCS coding is found in the
Coding and Programming selection from the start screen or when pressing the Change
button. Follow on-screen instructions to remove KL 30 power to the IHKR control unit.
This step is necessary to complete the coding process.
Car and Key Memory
When troubleshooting complaints with the E46 IHKR it is important to note that because
the Car/Key Memory feature can change the operation of the system, a review of the settings should be made prior to beginning troubleshooting.
80
DSC III
kjhsdfkhsdflkhsdlkfjhlkjghkg
lkdkfljdflkjdsfljdslfjldskjflkjdflk
ldsflsdfklhdsfhsdfhsdkhfkhsdf
kldjfkljdfkjdskfkjdskfjkljdfkldsfk
kjsdfkljsdfkdsfkjdsfkljsdfkjds
ldjsfklkjsdfkldsjfkdsjfkdsfkdfklk
60
D-Bus
40
12
11
0
20
80
60
200
40
220
240
20
UNLEADED GASOLINE ONLY
3
100
120 140
100
160
180
2
120
140
5030 20 15
12
7
!
miles
BRAKE
ABS
EML
W DIS
BMW DIS
K-Bus
BMW DIS
BM
5
6
0
km/h
MPH
SERVICE
ENGINE
SOON
4
1/min
x1000
1
0
1
2
3
4
Print
Change
End
Services
BMW Coding/programming SELECTION
1
2
3
4
5
6
CAR MEMORY
KEY MEMORY
ZCS CODING
PROGRAMMING
ALIGNMENT EWS-DME
ALIGNMENT EWS-DDE
Note
Only Key Memory selections are possible for the E46 IHKR. The selections are:
•
•
•
Set Blower Power (Raise, Normal, Lower)
Correction Set Temperature (raise/lower)
A/C on at key on (Automatic activation of the compressor control when the ignition is
switched on.)
38
E46 Climate Control
Review Questions
1. Where is the interior temperature sensor located in a vehicle equipped with IHKA? What
is this input used for?
2. How does the IHKA control the auxiliary fan? What inputs are used by the IHKA to
determine the fan speed?
4. A customer complains that every time he enters his car the AC compressor is switched
on automatically. What could be causing his complaint?
5. Describe briefly how the influence of Solar radiation affects the IHKA settings.
6. How can a technicaian test for the correct operation of the Solar Sensor?
7. What is the purpose for the RPM input to the IHKA?
39
E46 Climate Control
Review Questions
8. What is the Voltage range of the control signal from the IHKR to the blower final stage?
9. Which components are responsible for the movement of the air distribution flaps? What
role does the air distribution micro-switch play? (IHKR system)
10. How does the IHKR determine a Y-factor if the system does not use an interior
temperature sensor?
11. How does the IHKR signal the DME when compressor activation is requested? Discuss
what information is exchanged.
12. What three stepper motors are located on the IHKR M-Bus? What is an M-Bus?
13. Which additional component is used in the rear defrost circuit of a convertible E46, as
compared to a hard top?
40
E46 Climate Control
Table of Contents
ENGINES
Subject
Page
M52TU. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Crankcase. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Crankshaft. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Pistons and Connecting Rods. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
Flywheel and Self Adjusting Clutch (SAC). . . . . . . . . . . . . . . . . . . . . .10
Oil Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Valve Train/VANOS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
VANOS Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Double Vanos Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Cylinder Head. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Cooling System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Map Cooling Thermostat. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
Resonance/Turbulence Intake System. . . . . . . . . . . . . . . . . . . . . . . . 18
Idle Control Valve and Turbulence Bores. . . . . . . . . . . . . . . . . . . . . . 19
Exhaust Manifolds. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Subject
Page
M54. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Mechanical Changes. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Technical Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .27
M52TU B25 AND B28 ENGINES
Model: E46, 323i and 328i
Production Date: M52TU B28: 6/98-6/00 M52TU B25: 6/98-9/00
Objectives
After completing this module you should be able to:
•
List the changes made to the M52TU from the previous M52 engine.
•
Describe the advantages offered by the use of Double Vanos valve control.
•
Understand the Mechanical, Hydraulic and Electronic controls used in Double
Vanos operation.
•
Explain the cooling system of the M52TU.
•
Describe the operation and advantages of the Turbulence Intake System.
3
Engines
Introduction
The M52 TU (Technically Updated) engine, is a further development of the M52 engine used
in E36 and E39 vehicles. It is available in two displacement versions, the 2.8 liter and the
2.5 liter.
The development objectives were to reduce the fuel consumption and emission levels,
while increasing the power output and performance characteristics of the previous M52.
The engine management system, Siemens MS42.0, was developed, in conjunction with the
mechanical changes, to provide the needed electronic control to allow the engine to comply with the Low Emission Vehicle (LEV) standards.
During development, particular importance was given to improving quality, engine acoustics
and comfort. Further development criteria was placed on increasing power
achieved by an improved torque curve.
4
Engines
Overview
The following changes were made to the M52 engine to achieve the development goals:
•
•
•
•
•
•
•
•
•
•
Re-designed crankcase
Modified crankshaft
Modified pistons
Oil pump/oil pressure regulator integrated into the oil sump deflector
Double VANOS for the camshaft drive
Re-designed cooling system
Map controlled thermostat
Quick disconnect hoses for cooling system
Motor driven throttle valve
Catalytic converters mounted in the exhaust manifold
5
Engines
TECHNICAL DATA
6
Engines
7
Engines
Crankcase
The crankcase of the M52 TU engine is a new design. It is made from the same aluminum
alloy as the crankcase for the Z3 Roadster 2.8 liter M52 engine.
• The aluminum crankcase is 51lbs lighter
than the cast iron block
of the M52.
• The engine has cast
iron liners as the M52
engine in the Z3.
• There is the possibility
for boring the cylinders
once (+.25mm).
Crankshaft
The crankshaft of the 2.5 liter displacement engine is made from cast iron. The 2.8 liter
engine uses a forged steel crankshaft due to the “higher torque”. Both crankshafts are
mass balanced. The crankshafts feature seven main bearings with the thrust bearing located at the #6 main journal area.
8
Engines
Pistons and Connecting Rods
The piston design is carried over from the M52 engine. The 2.8 liter uses a graphite coating on the skirts to reduce friction and noise characteristics. The connecting rods are forged
steel.
9
Engines
Flywheel and Self Adjusting Clutch (SAC)
The M52 TU uses the dual mass flywheel with the self adjusting clutch introduced on the
E39.
The SAC is designed to extend the service life of
the clutch disc while keeping the pivot range of the
diaphragm spring consistent throughout its service
life.
To check the clutch disc thickness the clutch must
be removed. The pressure plate of the SAC configuration incorporates an additional “wedge” ring
that rotates as the disc wears. As the ring rotates
(1/2” total rotation distance) its wedges push the
pressure plate disc forward to compensate for the
wear of the clutch disc.
When a SAC pressure plate is removed it must be
reset to the “new” position before installing it into
the vehicle. Using a new special tool, the wedge
ring (1) is rotated back under the pressure of the
spring (2) to the “new” reference line on the pressure plate.
CAUTION: A replacement pressure plate is
received with a shipping “star lock”. This is to be
removed after installation. SAC service and
replacement procedures are different and require
new special tools. Refer to the repair manual in TIS
for complete procedures.
10
Engines
Oil Pump
The duocentric oil pump with oil pressure regulator for the M52 TU engine is integrated into
the oil deflector in the sump.
11
Engines
VANOS
The double VANOS system is used on the M52 TU engine. Double VANOS was originally
introduced on the European M3 engine, however, the system for the M52 TU engine is
designed specifically for series production engines.
The single VANOS system of the M52 engine is a simple ON/OFF system. With the double
VANOS system, true variable timing for both the intake and exhaust camshafts is possible.
In addition to offering increased power, the double VANOS system offers the following
advantages:
• Increase torque in the lower and medium RPM ranges - without a loss of power in the
upper RPM ranges
• Less un-burned gas when idling due to less camshaft overlap
• Improved idling characteristics due to less overlap
• Internal exhaust gas recirculation in the part load range for lower NOx emissions
• Quicker warm up cycle for the catalytic converter for faster reduction in emissions
• Improved fuel economy
12
Engines
VANOS Components
The VANOS system consists of the following components:
•
•
•
•
•
•
Intake and Exhaust camshafts with helical gear inserts
Adjustable camshaft drive gears
Double VANOS actuator
2 - three way solenoid valves
Two camshaft trigger wheels
Two camshaft position sensors
Engine oil pressure is used to position the VANOS actuators. The oil pressure is fed from
the pump up to the three way solenoids and drains back to the sump as the camshafts are
adjusted during engine operation.
TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
MS42.0
ECM
SENSOR
KL 15
SOLENOID
SENSOR
VENT
KL 15
VENT
SOLENOID
MS42.0
ECM
TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY
OIL TEMP.
SENSOR
MS42.0
With the double VANOS system, the camshafts are infinitely adjustable within the mechanical travel limits of the cam drive gears.
13
Engines
Double VANOS Operation
The MS42.0 engine control module (ECM) controls the operation of the Double VANOS system. The base setting of the camshafts with the engine off:
• Intake cam - retarded
• Exhaust cam - advanced
This is also the "fail safe" position in the event of an electronic control failure. Both
camshafts are held in these positions by oil pressure from the engine oil pump. The exhaust
camshaft is held additionally by a spring in the VANOS actuator.
When the engine is started, the camshafts will remain in these positions until the ECM
detects the positions of the camshafts from the camshaft sensors (approximately 50 revolutions or 2- 5 seconds).
Once the cam positions are recognized, the ECM will make an initial cam timing adjustment
based on RPM and throttle position. Following this initial setting, the intake air and engine
coolant temperature are used to adjust the timing.
When the ECM detects that the cams are in the desired position, the solenoids are modulated (100 - 220 Hz) maintaining oil pressure on both sides of the actuators to maintain the
camshaft timing.
14
Engines
Cylinder Head
The cylinder head has been redesigned in the area of the cooling passages. The coolant
circulation through the head has been optimized, allowing the head to operate at cooler
temperatures.
The front of the cylinder head has been redesigned for the double VANOS system.
The air intake ports have been redesigned in conjunction with the redesigned intake manifold.
Secondary Air
Porting
Intake
Turbulence
Manifold
Port
Exhaust
Coolant Passage
(casting)
15
Engines
Cooling System
The cooling system of the M52 TU engine has been completely redesigned. The objective
in redesigning the system was to optimize the operating temperatures in both cylinder head
and block. The cooling system is designed to:
• Reduce the operating temperatures of the cylinder head. This has a positive effect on
torque because the lower temperatures improve the volumetric efficiency of the engine.
• Increase the operating temperature of the cylinder block (crankcase). This design change
reduces the friction and thereby reduces fuel consumption.
16
Engines
These two changes were achieved in the M52 TU by having the coolant flow directly to the
cylinder head from the water pump. The system is referred to as a partial engine cooling
concept (MTK).
The coolant is fed by the water pump through a cast coolant feed passage in the cylinder
head to the rear of the cylinder head. From there it flows forward to the thermostat housing, radiator and output to the controlled inlet of the heater core.
The water passages in the cylinder block are only connected to the coolant supply and
metered through the holes in the head gasket. A reduced volume of the coolant flows
through the cylinder block.
Map Cooling Thermostat
As a further measure for controlling the
engine's operating temperature, the
heated thermostat, introduced on the
M62 engine, is carried over to the M52
TU engine. The heated thermostat
allows the engine to be operated at
higher controlled temperatures during
low and part throttle conditions which
reduces the fuel consumption of the
engine.
The thermostat heating which opens
or closed the thermostat to control the
engine temperature is controlled by the
DME. Any problems will be diagnosed
as part of the DME system using the
DIS or MoDiC.
17
Engines
Resonance/Turbulence Intake System
The intake manifold for the M52 TU engine was completely redesigned. Manufactured from
molded plastic, it contained several new innovations and features.
Resonance Charging
The principle of resonance charging is carried over from the M42 engine. The design of the
manifold and the use of the resonance charging flap allow the manifold to operate with the
dynamic effect of long intake runners at low to mid range RPM. Then, when the resonance
flap opens during higher RPM, the dynamic effect is to have six short intake runners for
greater air volume.
The overall effect is to achieve an optimum torque progression throughout the entire RPM
range.
The resonance system consists of:
•
•
•
•
•
•
The intake manifold
Resonance manifold and tubes
Main manifold with six ram tubes
The resonance flap and controls
Vacuum actuator and vacuum reservoir
Turbulence manifold and idle control valve
MAIN MAINIFOLD
RAM TUBE
MS-42
RESONANCE TUBE
MAGNETIC
VALVE
MDK
HFM
VACUUM
UNIT
RESONANCE
FLAP
IDLE AIR CONTROL VALVE
(ZWD)
RESONANCE MANIFOLD
CRANKCASE VENTILATION
TURBULENCE MANIFOLD
TURBULENCE BORE 0:5.5mm
18
Engines
Idle Control Valve and Turbulence Bores
The intake manifold incorporates six separate (internal) turbulence bores that channel the
idle and low engine speed air directly into the cylinder head. The turbulence bores mate up
to matching 5.5mm bores in the cylinder head.
OUTLET-VANOS
(228/80-105)
INLET-VANOS
(228/80-120)
SECONDARY
AIR
INJECTION
(AIR FILTER)
MDK
INT. EGR
INLET
TURBULENCE
IDLE AIR
CONTROL VALVE
CATALYST
CLOSE TO
ENGINE
19
Engines
Exhaust Manifolds
The exhaust manifolds incorporate the catalytic converters. Mounting the catalytic
converters close to the engine allows them to come up to operating temperature quicker.
The two pre and two post catalytic oxygen sensors are also mounted in the exhaust
manifold.
PRE-CATALYST SENSORS
POST-CATALYST
SENSORS
20
Engines
M54 B25 AND B30 ENGINES
Model: E46, 325i and 330i
Production Date: M54 B30: From 6/00 M54 B25: From 9/00
Objectives
After completing this module you should be able to:
• Identify the changes to the M54 engines over the M52 TU engine.
• List the design objectives for the M54 engine.
21
Engines
Introduction
The M54 - 6 cylinder engine was introduced with the 2001 Model Year E46 330i. The displacement of the new engine is 3 liters and the engine replaced the 2.8 liter engine in the
E46 in 6/2000. A 2.5 liter version of the M54 engine was introduced starting with 9/2000
production in the E46, Z3 and E39 vehicles.
The M54 - 3 liter displacement engine meets ULEV compliancy for emission standards. The
2.5 liter version of the M54 engine is LEV compliant.
Design objectives for the M54 engine were to provide:
• Lower Emissions
• Maintain Fuel Economy
• Maintain Power and Performance levels
HORSE POWER
M54B30
231@5900RPM
TORQUE
300Nm@3500RPM 245Nm@3500RPM
BORE
STROKE
COMPRESSION
22
Engines
84mm
89.6mm
10.2:1
M54B25
192@6000RPM
84mm
75mm
10.5:1
Mechanical Changes
In addition to the increased displacement of the M54B30 engine, several mechanical
changes were incorporated into the engine for reduced emissions and increased fuel economy. These changes include:
•
NEW PISTONS - The pistons have a shorter skirt compared to the M52TU and
continue with the graphite coating for friction and emission reducing measures. The
piston rings have been modified to reduce friction.
•
CRANKSHAFT - The crankshaft for the 3 liter M54 is adopted from the S52B32 M3 engine. The crankshaft for the 2.5 liter is carried over from M52TU.
•
CAMSHAFT - The camshaft for the 3 liter M54 is modified with more lift (9.7 mm)
and new valve springs to accommodate the increased lift. The camshaft of the 2.5
liter M54 is carried over from the M52TU engine.
•
INTAKE MANIFOLD - The intake manifold is modified with shorter ram tubes (20mm
shorter on 3 liter/10mm shorter on 2.5 liter). The diameter of the tubes is increased
slightly.
•
INJECTION VALVES - The diameter of the injection pintle has increased slightly for
the increased displacement of the 3 liter engine. The injectors for the 2.5 liter engine
carry over from the M52TU.
23
Engines
Non-return Fuel Rail system
The M54 engine with MS 43.0 control uses the non return fuel rail system introduced on
the M62 TU engine. The system meets running loss compliance without the use of the 3/2way (running losses) solenoid valve used on the M52TU engine.
The regulated fuel supply is controlled by
the fuel pressure regulator integrated in
the fuel filter. The fuel return line is also
located on the filter.
The M54 engine uses an Electronic
Controlled Throttle Valve (EDK) for intake
air control. The idle control valve and turbulence function of the intake manifold
carries over from the M52TU engine.
24
Engines
M54B30 ENGINE
231
25
Engines
M54B25 ENGINE
26
Engines
Review Questions
1. What position are the camshafts in when the engine is first started? What advantages
does this position make possible?
2. How much mechanical movement does the Vanos assembly provide?
3. Why is it advantages to maintain a warm crankcase but continue to keep the
cylinder head cool? What is the purpose of the transmission heat exchanger?
4. What effect is caused by the turbulence bores in the combustion chamber?
5. How does the M52TU/M54 achieve EGR without using a separate valve?
6. Why are the Catalytic Converters mounted so close to the engine?
7. What change was made to the fuel delivery system of the M54?
27
Engines
Table of Contents
ENGINE MANAGEMENT SYSTEMS
Subject
Page
SIEMENS MS 42.0 ENGINE CONTROL SYSTEM. . . . . . . . . . . . . . . . . . . . . . 3
Overview/On Board Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Emission Compliance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
Driving Cycle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Federal Test Procedure (FTP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
“Check Engine” (MIL) Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
Diagnostic Trouble Codes (DTC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
20 Pin Diagnostic Socket Deletion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
BMW Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Engine Management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
I-P-O . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
Scope of Input Functions
BOSCH Oxygen Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Camshaft Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Crankshaft Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
Misfire Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Mass Air Flow (HFM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Scope of Output Functions
VANOS control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Electric Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Running Losses. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
Secondary Air Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Fuel Injection Valves. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
Engine/Vehicle Speed Limitation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .35
RZV Ignition System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Resonance/Turbulence Intake System. . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Idle Speed Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Intake Jet Pump . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Purge Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Torque Interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Subject
Page
Leakage Diagnosis Pump (LDP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Motor Driven Throttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Intake Air Flow Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
SIEMENS MS 43.0 ENGINE CONTROL SYSTEM. . . . . . . . . . . . . . . . . . . . . .57
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
MS 43.0 New Functions
Electronic Throttle Control (EML). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Accelerator Pedal Sensor (PWG). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Electronic Throttle Valve (EDK). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Main Relay Monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Engine Optimized ignition Key Off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Diagnosis Module Tank Leakage (DM-TL). . . . . . . . . . . . . . . . . . . . . . . . 67
DM-TL Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
DM-TL Test Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
SIEMENS MS 42.0 ENGINE CONTROL SYSTEM
Model: E46 equipped with M52TU Engine
Production Dates: M52TU B28: 6/98 to 6/00, M52TU B25: 6/98 to 9/00
Objectives
After completing this module you should be able to:
•
Describe the engine management system monitoring required by OBD II regulation.
•
Explain what is required in-order for the ECM to illuminate the MIL.
•
Understand how the ECM monitors for misfires.
•
Explain the relationship between the MDK and idle control valve.
•
Describe the operation of the resonance charging manifold.
•
List the procedure the ECM uses to carry out the tank leakage test.
•
Recognize the fail-safe running characteristics of the MDK safety concept.
OBD II FUNCTION: Overview (On Board Diagnosis)
Since the 1996 model year all vehicles must meet OBD II requirements. OBD II requires the
monitoring of virtually every component that can affect the emission performance of a vehicle plus store the associated fault code and condition in memory. If a problem is detected,
the OBD II system must also illuminated a warning lamp (Malfunction Indicator Light - MIL/
“Check Engine Light”” located on the vehicle instrument panel to alert the driver that a malfunction has occurred. In order to accomplish this task, BMW utilizes the Engine Control
Module (ECM/DME) as well as the Automatic Transmission Control Module (EGS/AGS) and
the Electronic Throttle Control Module (EML) to monitor and store faults associated with all
components/systems that can influence exhaust and evaporative emissions.
4
Engine Management Systems
OVERVIEW OF THE NATIONAL LOW EMISSION
VEHICLE PROGRAM
Emission Reduction Stages:
While OBD II has the function of monitoring for emission related faults and alerting the operator of the vehicle, the National Low Emission Vehicle Program requires a certain number
of vehicles produced (specific to manufacturing totals) currently comply with the following
emission stages;
TLEV: Transitional Low Emission Vehicle
LEV: Low Emission Vehicle
ULEV: Ultra Low Emission Vehicle.
Prior to the National Low Emission Vehicle Program, the most stringent exhaust reduction
compliancy is what is known internally within BMW as HC II. The benefit of exhaust emission reductions that the National Low Emission Vehicle Program provides compared with
the HC II standard is as
Cold Engine Startup - 50 O F
follows:
TLEV- 50% cleaner.
LEV- 70% cleaner.
ULEV-84% cleaner.
Compliance
Level
TLEV
LEV
ULEV
Compliance
Level
TLEV
LEV
ULEV
Compliance
Level
TLEV
LEV
ULEV
Grams/Mile - “New”
NMHC
CO
NOx
Non Methane
Hydrocarbon
Carbon Monoxide
Oxide(s) of Nitrogen
0.250
0.131
0.040
3.4
3.4
1.7
0.4
0.2
0.2
Grams/Mile at 50,000 miles
NMHC
CO
NOx
Non Methane
Hydrocarbon
Carbon Monoxide
Oxide(s) of Nitrogen
0.125
0.075
0.040
3.4
3.4
1.7
0.4
0.2
0.2
Grams/Mile at 100,000 miles
NMHC
CO
NOx
Non Methane
Hydrocarbon
Carbon Monoxide
Oxide(s) of Nitrogen
0.156
0.090
0.055
4.2
4.2
2.1
0.6
0.3
0.3
5
Engine Management Systems
OBD II EVAPORATIVE EMISSION COMPLIANCE
1995
1996
M44/
E36
HC II
START 1/96
M44/
Z3
1998
TLEV
BP 1/97
HC II
START 10/96
M52/
E36
M52/
M52TU
E46
1997
TLEV
BP 1/97
TLEV
START 10/95
LEV
START 6/98
M52/
M52TU
E39
TLEV
START 3/96
M52/
M52TU
Z3
LEV
TLEV
START 1/97
M62/
M52TU
E38/39
BP 9/98
LEV
BP 9/98
HC II
M73/
M52TU
E38
START 1/95
LEV
START 1/96
BP 6/98
HC II
LEV
è
è
è
è
è
è
è
è
BP 9/98
OBD II EVAPORATIVE EMISSION COMPLIANCE
1995
M44/
E36
M44/
Z3
1996
1997
PURGE FLOW
MONITORING
START 1/96
PURGE FLOW
MONITORING
è è
3/2 VALVE
1998
PURGE FLOW MONITORING
SMALL LEAK DETECTION (1mm) 3/2 VALVE
BP 1/97
PURGE FLOW MONITORING
SMALL LEAK DETECTION (1mm) 3/2 VALVE
START 10/96
BP 1/97
PURGE FLOW MONITORING
SMALL LEAK DETECTION (1mm) 3/2 VALVE
M52/
E36
START 10/95
M52/
E46
M52/
E39
LDP 0.5mm
ORVR 3/2
PURGE FLOW MONITORING
3/2 VALVE
START 3/96
M52/
Z3
M62/
E38
E39
M73/
E38
6
Engine Management Systems
START 6/98
LDP PUMP 1mm
LDP 0.5mm
LEAK ORVR 3/2
ORVR 3/2
VALVE
BP 9/97
BP 9/98
PURGE FLOW MONITORING
LDP 0.5mm
SMALL LEAK DETECTION (1mm) 3/2
ORVR 3/2
VALVE
START 1/97
PURGE FLOW MONITORING
3/2 VALVE
START 1/96
PURGE FLOW MONITORING
3/2 VALVE
LDP PUMP 1mm LEAK
ORVR 3/2 VALVE
BP 9/98
LDP 0.5mm
ORVR 3/2
BP 5/97
BP 6/98
LDP PUMP 1mm LEAK ORVR
LDP 0.5mm
3/2 VALVE
ORVR 3/2
è
è
è
è
è
è
è
è
OBD II FUNCTION: DRIVING CYCLE
As defined within CARB mail-out 1968.1:
"Driving cycle" consists of engine startup and engine shutoff.
"Trip" is defined as vehicle operation (following an engine-off period) of duration and driving style so that all components and systems are monitored at least once by the diagnostic
system except catalyst efficiency or evaporative system monitoring. This definition is subject to the limitations that the manufacturer-defined trip monitoring conditions are all monitored at least once during the first engine start portion of the Federal Test Procedure (FTP).
Within this text the term "customer driving cycle" will be used and is defined as engine
start-up, operation of vehicle (dependent upon customer drive style) and engine shut-off.
7
Engine Management Systems
FEDERAL TEST PROCEDURE (FTP)
The Federal Test Procedure (FTP) is a specific driving cycle that is utilized by the EPA to
test light duty vehicles and light duty truck emissions. As part of the procedure for a vehicle manufacturer to obtain emission certification for a particular model/engine family the
manufacturer must demonstrate that the vehicle(s) can pass the FTP defined driving cycle
two consecutive times while monitoring various components/systems. Some of the
components/systems must be monitored either once per driving cycle or continuously.
1. Components/systems required to be monitored once within one driving cycle:
•
Oxygen Sensors
•
Secondary Air Injection System
•
Catalyst Efficiency
•
Evaporative Vapor Recovery System
NOTE: Due to the complexity involved in meeting the test criteria within the FTP defined
driving cycle, all tests may not be completed within one "customer driving cycle". The
test can be successfully completed within the FTP defined criteria, however customer
driving styles may differ and therefore may not always monitor all involved components/systems in one "trip".
Components/systems required to be monitored continuously:
•
Misfire Detection
•
Fuel system
•
Oxygen Sensors
•
All emissions related components/systems providing or getting electrical connections to
the DME, EGS, or EML.
8
Engine Management Systems
The graph shown below is an example of the driving cycle that is used by BMW to complete the FTP.
The diagnostic routine shown above will be discontinued whenever:
• Engine speed exceeds 3000 RPM
• Large fluctuations in throttle angle
• Road speed exceeds 60 MPH
NOTE: The driving criteria shown can be completed within the FTP required ~11 miles in a
controlled environment such as a dyno test or test track.
A "customer driving cycle" may vary according to traffic patterns, route selection
and distance traveled, which may not allow the "diagnostic trip" to be fully completed each time the vehicle is operated.
9
Engine Management Systems
OBD II FUNCTION: "CHECK ENGINE" (MIL) LIGHT
In conjunction with the CARB/OBD II regulations the "CHECK ENGINE" light (also referred to
as the Malfunction Indicator Light - MIL) is to be illuminated:
•
Upon the completion of the second consecutive driving cycle where the previously faulted system is monitored again and the emissions relevant fault is again present.
•
Immediately if a catalyst damaging fault occurs (see Misfire Detection).
The illumination of the check engine light is performed in accordance with the Federal Test
Procedure (FTP) which requires the lamp to be illuminated when:
•
A malfunction of a component that can affect the emission performance of the vehicle
occurs and causes emissions to exceed 1.5 times the standards required by the (FTP).
•
Manufacturer-defined specifications are exceeded.
•
An implausible input signal is generated.
•
Catalyst deterioration causes HC-emissions to exceed a limit equivalent to 1.5 times the
standard (FTP).
•
Misfire faults occur.
•
A leak is detected in the evaporative system
•
The oxygen sensors observe no purge flow from the purge valve/evaporative system.
•
Engine control module fails to enter closed-loop operation within a specified time interval.
•
Engine control or automatic transmission control enters a "limp home" operating mode.
•
Key is in the "ignition" on position before cranking (Bulb Check Function).
Within the BMW system the illumination of the check engine light is performed in accordance with the regulations set forth in CARB mail-out 1968.1 and as demonstrated via the
Federal Test Procedure (FTP). The following information provides several examples of when
and how the "Check Engine" Light is illuminated based on the "customer drive cycle" (DC):
10
Engine Management Systems
1. A fault code is stored within the respective control module upon the first occurrence of
a fault in the system being checked.
2. The "Check Engine" (MIL) light will not be illuminated until the completion of the second
consecutive "customer driving cycle" where the previously faulted system is again monitored and a fault is still present or a catalyst damaging fault has occurred.
3. If the second drive cycle was not complete and the specific function was not checked
as shown in the example, the engine control module counts the third drive cycle as the
“next consecutive“ drive cycle. The check engine light is illuminated if the function is
checked and the fault is still present.
4. If there is an intermittent fault present and does not cause a fault to be set through multiple drive cycles, two complete consecutive drive cycles with the fault present are
required for the Check Engine light to be illuminated.
5. Once the "Check Engine" light is illuminated it will remain illuminated unless the specific function has been checked without fault through three complete consecutive drive
cycles.
6. The fault code will also be cleared from memory automatically if the specific function is
checked through 40* consecutive drive cycles without the fault being detected or with
the use of either the DIS, MODIC or Scan tool.
* NOTE: In order to clear a catalyst damaging fault (see Misfire Detection) from memory, the condition under which the fault occurred must be evaluated for 80 consecutive
cycles without the fault reoccurring.
With the use of a universal scan tool, connected to the "OBD" DLC an SAE standardized
DTC can be obtained, along with the condition associated with the illumination of the
"Check Engine" light.
Using the DIS or MODIC, a fault code and the conditions associated with its setting can
be obtained prior to the illumination of the "Check Engine" light.
11
Engine Management Systems
OBD II DIAGNOSTIC TROUBLE CODES (DTC)
The Society of Automotive Engineers (SAE) established the Diagnostic Trouble Codes used
for OBD II systems (SAE J2012). The DTC’s are designed to be identified by their
alpha/numeric structure. The SAE has designated the emission related DTC’s to start with
the letter “P” for Powertrain related systems, hence their nickname “P-code”.
P
For example:
0
4
4
0
P-Powertrain, B-Body, C-Chassis
DTC Source; 0-SAE, 1-BMW
System; 0-Total System
1-Air/Fuel Induction
2-Fuel Injection
3-Ignition System or Misfire
4-Auxiliary Emission Control
5-Vehicle Speed & Idle Control
6-Control Module Inputs/Outputs
7-Transmission
Sequentially numbered
fault identifying individual
components or circuits
(00-99)
•
DTC’s are stored whenever the Check Engine Light (MIL) is illuminated.
•
A requirement of CARB/EPA is providing universal diagnostic access to DTC’s via a
standardized Diagnostic Link Connector (DLC) using a standardized tester (scan tool).
•
DTC’s only provide one set of environmental operating conditions when a fault is stored.
This single "Freeze Frame" or snapshot refers to a block of the vehicles environmental
conditions for a specific time when the fault first occurred. The information which is
stored is defined by SAE and is limited in scope. This information may not even be specific to the type of fault.
DTC Storage:
The table represents
the stored information
that would be available via an aftermarket scan tool if the
same fault occurred 5
times.
12
Engine Management Systems
Bosch Systems
initial fault
2 nd occurrence
3 rd occurrence
last occurrence
Aftermarket Scan Tool
SAE defined freeze frame conditions
n/a
n/a
n/a
Siemens Systems
initial fault
Aftermarket Scan Tool
SAE defined freeze frame conditions
Scan Tool Connection (to 6/00)
Starting with the 1995 750iL, and soon
after on all 1996 model year BMW vehicles, a separate OBD II Diagnostic Link
Connector (DLC) was added.
The DLC provides access for an aftermarket scan tool to all emission related control
systems (DME, AGS/EGS and EML). This
diagnostic communication link uses the
existing TXD II circuit in the vehicle through
a separate circuit on the DLC when the 20
pin cap is installed.
Scan Tool Display
Example: A fault was induced into a 1998
750iL by removing the wire connector from Air DTC
Mass Meter. Using an aftermarket scan tool ENGINE SPD
ECT
the following information can be displayed:
DIAG. TROUBLE
CODES
ECU:
Number of DTCs:
*P0100
ENTER =
$12 (Engine)
1
Manufacturer
controlled fuel and air
metering
FREEZE FRAME
VEHICLE SPD
ENGINE LOAD
FUEL STAT 1
FUEL STAT 2
ST FT 1
LT FT 1
ST FT 2
LT FT 2
P0100
905 RPM
160 F
0 MPH
3.9%
OL
OL
0.0%
1.6%
0.0%
3.1%
13
Engine Management Systems
20 PIN DIAGNOSTIC SOCKET DELETION
Model: E39,E46,E52,E53
Production Date: E46 from 6/00
E39,E52,E53 from 9/00
For model year 2001 the E39, E46 and E53 will eliminate the 20 pin diagnostic connector
from the engine compartment. The 16 pin OBD II connector located inside the vehicle will
be the only diagnosis port.
The E38 and Z3 will continue to use the 20 pin connector.
The 16 pin OBD II connector has been in all
BMWs since 1996 to comply with OBD II
regulations requiring a standardized diagnostic
port.
Previously before 2001, only emissions relevant
data could be extracted from the OBD II
connector because it did not provide access to
TXD (D-bus). The TXD line is connected to pin
8 of the OBD II connector on vehicles without
the 20 pin diagnostic connector.
The cap to the OBD II connector contains a
bridge that links KL 30 to TXD and TXD II. This
is to protect the diagnostic circuit integrity and
prevent erroneous faults.
The OBD II connector is located in the drivers
footwell to the left of the steering column of
E39, E46 and E53 vehicles.
14
Engine Management Systems
Diagnostics Via the OBD II Connector
DSC III
kjhsdfkhsdflkhsdlkfjhlkjghkg
lkdkfljdflkjdsfljdslfjldskjflkjdflk
ldsflsdfklhdsfhsdfhsdkhfkhsdf
kldjfkljdfkjdskfkjdskfjkljdfkldsfk
kjsdfkljsdfkdsfkjdsfkljsdfkjds
ldjsfklkjsdfkldsjfkdsjfkdsfkdfklk
DIS
BMW DIS
BMW
BMW DIS
DIS/MoDiC
CONNECTOR
OBD II
16 9
CONNECTOR
7
TXD
20
3
100
120 140
100
160
180
2
120
4
5
1/min
x1000
6
1
200
220
240
20
140
0
km/h
5030 20 15
12
1
KL 31
7
MPH
miles
BRAKE
ABS
IKE/KOMBI
AGS
I/K-BUS
TD (RPM)
KL 30
DME
+
80
60
40
11
4
DME
-
80
60
40
12
0
UNLEADED GASOLINE ONLY
5
TXD II
8
KL 15
DSC
15
Engine Management Systems
BMW FAULT CODE (DIS/MoDiC)
•
BMW Codes are stored as soon they occur even before the Check Engine Light (MIL)
comes on.
•
BMW Codes are defined by BMW, Bosch, and Siemens Engineers to provide greater
detail to fault specific information.
•
Siemens systems - (1) set of (4) fault specific environmental conditions are stored with
the first fault occurrence. This information can change and is specific to each fault code
to aid in diagnosing. A maximum of (10) different faults containing (4) environmental conditions can be stored.
•
Bosch Systems - a maximum of (4) sets of (3) fault specific environmental conditions are
stored within each fault code. This information can change and is specific to each fault
code to aid in diagnosing. A maximum of (10) different faults containing (3) environmental conditions can be stored.
•
BMW Codes also store and displays a "time stamp" when the fault last occurred.
•
A fault qualifier gives more specific detailed information about the type of fault (upper
limit, lower limit, disconnection, plausibility, etc.).
•
BMW Fault Codes will alert the technician of the current fault status. He will be advised
if the fault is actually still present, not currently present or intermittent. The fault specific information is stored and accessible through DIS or Modic.
•
BMW Fault Codes determine the diagnostic output for BMW DIS and Modic.
BMW Fault Code Storage:
The table below represents the information that would be available via the DIS tester if the
same fault occurred 5 times.
Bosch Systems
initial fault
2nd occurrence
3rd occurrence
last occurrence
Siemens Systems
initial fault
16
Engine Management Systems
DIS Tester Information
3 fault specific environmental conditions with time stamp,
counter, and if fault is currently present or intermittent
3 fault specific environmental conditions with time stamp,
counter, and if fault is currently present or intermittent
3 fault specific environmental conditions with time stamp,
counter, and if fault is currently present or intermittent
3 fault specific environmental conditions with time stamp,
counter, and if fault is currently present or intermittent
DIS Tester Information
4 fault specific environmental conditions with time stamp,
counter, and if fault is currently present or intermittent
SIEMENS ENGINE MANAGEMENT SYSTEM
This Siemens system is designated as MS42.0.
Siemens MS42.0 was developed to
meet the needs of Low Emission
Vehicle (LEV) compliancy and OBD
II. This system also includes control
of the Motor-driven Throttle Valve
(MDK).
The ECM uses a pc-board singleprocessor control unit in the new
SKE housing. Mounted in the E-Box
(next to brake master cylinder). The
MS 42.0 ECM is flash programmable as seen with previous systems.
ECM hardware includes:
Modular plug connectors featuring 5 connectors in the SKE housing with 134 pins.
•
•
•
•
•
Connector
Connector
Connector
Connector
Connector
1
2
3
4
5
=
=
=
=
=
Supply voltages and grounds
Peripheral signals (oxygen sensors, CAN, etc.)
Engine signals
Vehicle signals
Ignition signals
Special features:
• Flash EPROM which is adaptable to several
M52 LEV engines and has the capability to
be programmed up to 13 times
• Once a control unit is installed and coded to a vehicle it cannot be swapped with another vehicle for diagnosing or replacement (because of EWS 3.3). A new ECM must be
installed if necessary.
17
Engine Management Systems
MS 42.0 I-P-O
ECM RELAY
CONTROL
KL 15
FUEL PUMP RELAY CONTROL
MEMORY POWER
AC COMPRESSOR
RELAY CONTROL
AUX KL 31
MAIN KL 31
ECM
RELAY
OPERATING POWER
SECONDARY AIR INJECTION
AIR PUMP RELAY CONTROL
RADIATOR OUTLET
TEMPERATURE SENSOR
AIR
INJ.
SOL.
RUN
LOSS
SOL.
INTAKE VANOS SOLENOID
KNOCK
SENSORS
EXHAUST VANOS SOLENOID
M
IDLE CONTROL VALVE
SEQUENTIAL FUEL INJECTOR CONTROL (6X)
CAMSHAFT POSITION
SENSOR (2)
IGNITION COILS CONTROL (6X)
MFL BUTTON PAD
AIRMASS SIGNAL
INTAKE
AIR
TEMP
MDK
02 SENSOR HEATING
E46
M52 TU
MS42.0
THROTTLE
POSITION
CLUTCH SWITCH
BRAKE LIGHT SWITCH
BRAKE LIGHT TEST SWITCH
ENGINE TEMPERATURE
M
RESONANCE-TURBULENCE
INTAKE SYSTEM
CRANKSHAFT
POSITION SENSOR
I/O
P
PRECAT
(2X)
POSTCAT
(2X)
COMPRESSOR CLUTCH
OUTPUT STAGE
ELECTRIC FAN
INTAKE JET PUMP SOLENOID VALVE
PURGE VALVE CONTROL
OIL TEMP
SENSOR
80
CHECK
ENGINE
40
120140
100
160
80
180
60
12
0
20
2
4
1/min
x1000
5
120
6
1
200
40
11
3
100
60
IGNITION MONITOR
220
240
20
140
UNLEADED GASOLINE ONLY
0
km/h
50302015
12
7
MPH
CAN
E46
IHKA K-BUS
80
0
120140
100
160
80
180
60
20
2
5
6
1
220
240
20
UNLEADED GASOLINE ONLY
km/h
140
0
TCM
4
1/min
x1000
120
200
40
11
3
100
60
40
12
50302015
12
7
CAN
MPH
THROTTLE
POSITION
(DK)
ABS/
ASC
VEHICLE SPEED INPUT
ABS/
ASC
MDK
MOTOR DRIVEN THROTTLE VALVE
ROLLING CODE
MAP-CONTROLLED
HEATED THERMOSTAT
+ LEAKAGE DIAGNOSIS PUMP
2X
PRE & POST
CAT CONV.
O2 SENSOR
MONITORING
2X
+
LEAKAGE DIAGNOSIS
PUMP
DIAGNOSIS
DIS
OBD II
18
Engine Management Systems
SCOPE OF INPUT FUNCTIONS
BOSCH OXYGEN SENSORS
The MS42.0 system uses Bosch LSH 25 oxygen sensors that function basically the same
as previously used (in Bosch systems). The voltage range is between 0 - 800 mV.
pre O2 sensor
post O2 sensor
The location has changed, the pre-cat sensors are mounted on top of the exhaust manifolds. The catalysts are now integral with the exhaust manifolds.
PRE-CATALYST SENSORS
POST-CATALYST
SENSORS
19
Engine Management Systems
OXYGEN SENSOR SIGNAL INFLUENCE ON INJECTOR “OPEN” TIME
The ECM monitors the:
• Amplitude of the signal (highest voltage or range sensor is producing)
• Switching time of the signal (how fast from lean to rich)
• Frequency of complete cycles (how many within a period of time)
These characteristics provide info to the ECM that reflect the overall condition of the sensor.
POST CATALYTIC CONVERTER SENSOR SIGNAL
The post catalyst O2 sensors monitor the efficiency of the catalyst as a requirement of OBD
II. This signal also provides feedback of the pre-catalyst sensors efficiency and can cause
the ECM to “trim” the ms injection time to correct for slight deviations.
Bosh Systems:
Catalyst Monitoring
(Normal Condition)
6
Pre Cat. Sensor
Post Cat. Sensor
• If the catalyst is operating efficiently, most of the
remaining oxygen in the exhaust gas is burned
(lack of O2 - “constant lean signal”).
VOLTAGE
5
4
3
2
1
0
0
The sensor signal fluctuates slightly in the higher
end of the voltage scale.
0.5
1
1.5
2
2.5
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
Time
Catalyst Monitoring
(Catalyst Defective)
6
Post Cat. Sensor
Pre Cat. Sensor
5
4
Voltage
• If the post sensor shows excessive fluctuations
(which echo the scope pattern of the pre sensor),
this indicates that the catalytic converter is not
functioning correctly and cannot consume the O2
(fault set).
3
3
2
1
0
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
6.5
7
7.5
8
Time
• If the post sensor fluctuations move out of the normal voltage “window”, this indicates
that the pre sensor is not performing properly due to slight deterioration. These systems
can also “trim” the ms injection time to compensate for this.
The constantly changing oxygen sensor input to the ECM is needed to correct the ms
injection time to ensure that the ideal air/fuel ratio is maintained.
20
Engine Management Systems
CAMSHAFT SENSOR
-INTAKE AND EXHAUST CAMSHAFTS
The "static" Hall sensors are used so that the camshaft positions are recognized once ignition is “on” - even before the engine is started.
The function of the intake cam sensor:
•
•
•
•
Cylinder bank detection for preliminary injection
Synchronization
Engine speed sensor (if crankshaft speed sensor fails)
Position control of the intake cam (VANOS)
The exhaust cam sensor is used for position control of the exhaust cam (VANOS)
If these sensors fail there are no substitute values, the system will operate in the fail-safe
mode with no VANOS adjustment. The engine will still operate, but torque reduction will be
noticeable.
NOTE: Use caution on repairs as not to bend the impulse wheels
TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
MS42.0
ECM
SENSOR
KL 15
SOLENOID
SENSOR
VENT
KL 15
VENT
SOLENOID
MS42.0
ECM
TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY
OIL TEMP.
SENSOR
MS42.0
21
Engine Management Systems
CRANKSHAFT SENSOR
The crankshaft sensor is a dynamic Hall-effect sensor (mounted through the engine block),
the signal is sent the moment the crankshaft begins to rotate.
The pulse wheel is mounted directly to the crankshaft.
22
Engine Management Systems
MISFIRE DETECTION
As part of the CARB/OBD regulations the engine control module must determine if misfire
is occurring and also identify the specific cylinder(s) and the severity of the misfire event,
and whether it is emissions relevant or catalyst damaging. In order to accomplish these
tasks the control module monitors the crankshaft for acceleration losses during firing segments of each cylinder based on firing order.
Misfire Detection Example: M52 (6 Cyl.) with Siemens System
The misfire/engine roughness calculation is derived from the differences in the period duration (T) of individual increment gear segments. Each segment period consist of an angular
range of 120° crank angle that starts 78° before Top Dead Center (TDC).
Increment gear wheel segment period measurement:
120°CA
78°
before
TDC
TDC0
TDC1
TDC2
TDC3
TDC4
TDC5
TDC0
Tn-3
Tn-2
Tn-1
Tn
Tn+1
Tn+2
Tn+3
Threshold determination
• If the combustion process in all cylinders is functioning correctly, the period duration of
each segment will be identical (i.e. T0 = T1 = T2 = T3 = T4 = T5).
• If a misfire is encountered in a cylinder, the period duration (T) of that cylinder will be
extended by a fraction of a millisecond (i.e. T3 > T0, T1, T2, T4, T5).
• All measured values of T are evaluated within the DME, corrected based on sensor adaptation and compared to a set of predetermined values that are dependent on engine
speed, load and engine temperature.
If the expected period duration is greater than the permissible value a misfire fault for the
particular cylinder is stored in the fault memory of the DME. Depending on the level of misfire rate measured the control unit will illuminate the "Check Engine" light, may cut-off fuel
to the particular cylinder and may switch lambda operation to open-loop. All misfire faults
are weighted to determine if the misfire is emissions relevant or catalyst damaging.
23
Engine Management Systems
EMISSIONS RELEVANT:
During an interval of 1000 crankshaft revolutions the misfire events of all cylinders are
added and if the sum is greater than a predetermined value a fault will be set identifying the
particular cylinder(s). The Check Engine light will be illuminated during and after the second cycle if the fault is again present.
CATALYST DAMAGING:
During an interval of 200 crankshaft revolutions the misfire events of all cylinders are added
and if the sum is greater than a predetermined value a fault will be set identifying the particular cylinders(s). The “Check Engine” lamp:
• On vehicles with a Siemens Control Module (M52 engines) - the lamp will immediately go
to a steady illumination since fuel to the injector(s) is removed. Fuel cut-off to the cylinder will resume after several (>> 7) periods of decel if crankshaft sensor adaptation is successfully completed or the engine is shut-off and restarted.
• On vehicles with a Bosch Control Module (M44, M62 & M73 engines) - the lamp will blink
as long as the vehicle is operated within the specific criteria under which the fault
occurred. Fuel to the misfiring cylinder is not cut-off as long as the “Check Engine” light
is blinking.
In each case the number of misfire events permitted is dependent on engine speed, load
and temperature map.
The process of misfire detection continues well after the diagnostic drive cycle requirements
have been completed. Misfire detection is an on-going monitoring process that is only discontinued under certain conditions.
Misfire detection is only disabled under the following conditions:
REQUIREMENTS
STATUS/CONDITION
Engine Speed
Engine Load
Throttle Angle
Timing
< 512 RPM
Varying/Unstable
Varying/Unstable
Timing retard request active (i.e. knock
control - ASC, AGS)
Up to 5 seconds after start-up
Up to 0.5 seconds after A/C activation
Active
Active
Active
Engine Start-up
A/C
Decel fuel cut-off
Rough road recognition
ASC Control
24
Engine Management Systems
OBD II - Misfire Faults
FAILED
COMPONENT
POSSIBLE FAULT
MISFIRE
EFFECT/LOCATION
FAILED
COMPONENT
POSSIBLE FAULT
MISFIRE
EFFECT/LOCATION
Spark plug
electrode gap too small
electrodes missing
electrodes oil/fuel soaked
affected cylinders
affected cylinders
affected cylinders
Camshaft
broken
Piston
hole in piston crown/piston
seized in bore
defective: i.e. oil bore
restricted/blocked
engine oil pressure built up
too slow
fuel pump, pressure too low
most likely more than one
cylinder affected
on the affected cylinders
electrodes oil/feul soaked
fouled
spark plug ceramic broken
oil level too high
oil foaming
oil level too high, oil/fuel fouled
heat range too cold
crank case ventilation defective
Spark plug connector
Ignition Coil
Connectors ignition
Injection Valve
wet, water or moisture
broken
internal defect, arcing
corrosion
pin backed out
plug loose
loose wire from connector
metal filing
leaking
Injector connectors
Intake/Exhaust valve
burnt or damaged
overrev:intake or exhaust
valves leaking (bent)
25
Engine Management Systems
Intake manifold leaks
carbon fouled
dirty/contaminated
corrosion
pin backed out
plug loose
loose wire from connector
intake plenum, unmetere air
leak (i.e. injector seals)
carbon built up (intake)
Hydraulic lash adjusters
(HVA)
affected cylinders
most likely more than
one cylinder affected
Fuel pressure
fuel filter restricted/ blocked
most likely more than
one cylinder affected
most likely more than
one cylinder affected
affected cylinders
affected cylinders
one or more cylinders
one or more cylinders
one or more cylinders
one or more cylinders
on the affected
cylinders
on the affected
cylinders
one or more cylinders
one or more cylinders
one or more cylinders
one or more cylinders
one or more cylinders
one or more cylinders
most likely more than
one cylinder affected
on the affected
cylinders
most likely more than
one cylinder affected
fuel pump, pressure build up
too slow after start
leaking fuel feed lines
pressure regulator defective
(metal filing)
running loss valve defective
fuel tank empty
siphon jet pump and fuel
tank empty
water in fuel tank
Fuel
Oxygen sensor
Purge sytem
Crank sensor/increment
wheel
Catalyst damaged
DME
high content oxygenated
non anti carbon additives
excessive mixture deviation
excessive rich mixture due
to high ambient temperature
blocked fuel tank vent inlet
incorrect input signal for
misfire detection
increment wheel loose
increment wheel damaged
gap between sensor and
increment wheel
fly wheel damaged
exhaust back pressure on
the affected bank
final stage igntion/injectors
on the affected cylinders
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely cyl. 1-3 (front
cylinders)
most likely more than one
cylinder affected
one or more cylinders
one or more cylinders
only the affected bank
one or more banks
all cylinders
all cylinders
all cylinders
affected segment
affected segment
only the afftected bank
all cylinder
MASS AIR FLOW SENSOR HFM
The Siemens mass air flow sensor is functionally the same as on previous systems. The
new designation - 2 Type B simply indicates that it is smaller in design.
26
Engine Management Systems
SCOPE OF OUTPUT FUNCTIONS
VANOS CONTROL
With the introduction of double VANOS, the valve timing is changed on both the intake and
the exhaust camshafts.
Double VANOS provides the following benefits:
• Torque increase in the low to mid (1500 - 2000 RPM) range without power loss in the
upper RPM range.
• Less incomplete combustion when idling due to less camshaft overlap (also improves
idle speed characteristics).
• Internal exhaust gas recirculation (EGR) in the part load range (reduces NOx and postcombustion of residual gasses in the exhaust)
• Rapid catalyst warm up and lower “raw” emissions after cold start.
• Reduction in fuel consumption
Double VANOS consists of the following parts:
• Intake and exhaust camshafts with helical gear insert
• Sprockets with adjustable gears
• VANOS actuators for each camshaft
• 2 three-way solenoid switching valves
• 2 impulse wheels for detecting camshaft position
• 2 camshaft position sensors (Hall effect)
The “initial” timing is set by gear positioning (refer to the Repair Instructions for details) and
the chain tensioner. As with the previous VANOS, the hydraulically controlled actuators
move the helical geared cups to regulate camshaft timing. The angled teeth of the helical
gears cause the pushing movement of the helical cup to be converted into a rotational
movement. This rotational movement is added to the turning of the camshafts and cause
the camshafts to “advance” or “retard”. The adjustment rate is dependent oil temperature,
oil pressure, and engine RPM.
27
Engine Management Systems
NOTE: With extremely hot oil temperatures Vanos is deactivated (Powerloss). If the oil is
too thick (wrong viscosity) a fault could be set.
When the engine is started, the camshafts are in the “fail-safe” position (deactivated). The
intake camshaft is in the RETARDED position - held by oil pressure from the sprung open
solenoid. The exhaust camshaft is in the ADVANCED position - held by a preload spring in
the actuator and oil pressure from the sprung open solenoid.
After 50 RPM (2-5 seconds) from engine start, the ECM is monitoring the exact camshaft
position.
The ECM positions the camshafts based on engine RPM and the throttle position signal.
From that point the camshaft timing will be varied based on intake air and coolant temperatures.
The double VANOS system is “fully variable”. When the ECM detects the camshafts are in
the optimum positions, the solenoids are modulated (approximately 100-220 Hz) maintaining oil pressure on both sides of the actuators to hold the camshaft timing.
CAUTION: The VANOS MUST be removed and installed exactly as described in the Repair
Instructions!
NOTE: If the VANOS camshaft system goes to the fail-safe mode (deactivated) there will
be a noticeable loss of power. This will be like driving with retarded ignition or starting from
a stop in third gear.
TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
MS42.0
ECM
SENSOR
KL 15
SOLENOID
SENSOR
VENT
KL 15
VENT
SOLENOID
MS42.0
ECM
TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY
OIL TEMP.
SENSOR
MS42.0
28
Engine Management Systems
DEACTIVATED
EXHAUST: Advanced
piston moved in
EXHAUST
TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
MS42
ECM
INTAKE
SENSOR
KL 15
INTAKE: Retard piston
moved out
SOLENOID
SENSOR
VENT
KL 15
VENT
SOLENOID
MS42.0
ECM
TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY
OIL TEMP.
SENSOR
MS42.0
ACTIVATED
EXHAUST: Advanced
piston moved out
EXHAUST
TWO POSITION PISTON
HOUSING WITH
INTERNAL/EXTERNAL
HELICAL GEAR CUP
MS42
ECM
INTAKE
SENSOR
KL 15
SOLENOID
INTAKE: Retard piston
moved in
SENSOR
VENT
KL 15
VENT
SOLENOID
MS42.0
ECM
TWO POSITION PISTON HOUSING
WITH INTERNAL/EXTERNAL
HELICAL GEAR CUP
ENGINE
OIL SUPPLY
OIL TEMP.
SENSOR
MS42.0
29
Engine Management Systems
The dual VANOS in conjunction with the variable intake manifold provides an additional
emission control feature.
Because of the improved combustion, the camshaft timing is adjusted for more overlap.
The increased overlap supports internal exhaust gas recirculation (EGR) which reduces
tailpipe emissions and lowers fuel consumption.
During the part load engine range, the intake camshaft overlap opens the intake valve. This
allows limited exhaust gas reflow the intake manifold.
The “internal” EGR reduces the cylinder temperature thus lowering NOx. This feature provides EGR without the external hardware as seen on previous systems.
OUTLET-VANOS
(228/80-105)
INLET-VANOS
(228/80-120)
SECONDARY
AIR
INJECTION
(AIR FILTER)
MDK
INT. EGR
INLET
TURBULENCE
IDLE AIR
CONTROL VALVE
CATALYST
CLOSE TO
ENGINE
30
Engine Management Systems
ELECTRIC FAN
The electric cooling fan is controlled by the ECM. The ECM uses a remote power output
final stage (mounted on the fan housing)
The power output stage receives power from a 50 amp fuse (located in glove box above
the fuse bracket). The electric fan is controlled by a pulse width modulated signal from the
ECM.
The fan is activated based on the ECM calculation (sensing ratio) of:
•
•
•
•
•
Coolant outlet temperature
Calculated (by the ECM) catalyst temperature
Vehicle speed
Battery voltage
Air Conditioning pressure (calculated by IHKA
and sent via the K-Bus to the ECM)
POWER
OUTPUT STAGE
MS42.0
Activation of the electric fan:
When the vehicle is first started the fan is activated briefly (20% of maximum speed), then
it is switched off. This procedure is performed for diagnostic purposes.
The voltage generated by the fan when it slows down (it becomes a generator at this time)
must meet the power output stages programmed criteria. This will confirm the RPM of the
fan, if this is not met the signal wire from the output stage is switched to ground and a fault
is set in memory.
NOTE: If the ECM indicates a fault check the fan for freedom of movement
After the initial test has been performed, the fan is brought up to the specified operating
speed. At 10% (sensing ratio) the fan runs at 1/3 speed. At a sensing ratio of between 9095% the fan is running at maximum speed. Below 10% or above 95% the fan is stationary.
The sensing ratio is suppressed by a hysteresis function, this prevents speed fluctuation.
When the A/C is switched on, the electric fan is not immediately activated.
After the engine is switched off, the fan may continue to operate at varying speeds (based
on the ECM calculated catalyst temperature). This will cool the radiator down form a heat
surge (up to 10 minutes).
31
Engine Management Systems
RUNNING LOSSES
The fuel circuit changeover (running losses) has not changed in
operation from the previous system. The attached fuel pressure
regulator no longer controls fuel
pressure influenced by vacuum
supply.
The ECM now determines the fuel
quantity compensation for manifold vacuum changes. This is
based on throttle position sensor,
air mass meter, load, etc. for precise compensation.
The maintained fuel pressure at the fuel distribution rail is a constat 3.5 Bar.
the vacuum line no longer connects to intake manifold vacuum, but is routed to the
crankcase cyclone separator ( in case of regulator diaphragm leakage).
32
Engine Management Systems
SECONDARY AIR INJECTION
This ECM controlled function remains unchanged from
the previous Siemens MS 41.1 system, however there
is a hardware change.
The Air Injection Inlet Valve mounts directly to the cylinder head, with a passageway machined through the
head. This eliminates the external Air Injection manifold
distribution pipes to the exhaust manifolds.
SECONDARY AIR INJECTION MONITORING
In order to reduce HC and CO emissions while the engine is warming up, BMW implemented the use of a Secondary Air Injection System. Immediately following a cold engine
start (-10 - 40°C) fresh air/oxygen is injected directly into the exhaust manifold. By injecting oxygen into the exhaust manifold:
• The warm up time of the catalyst is reduced
• Oxidation of the hydrocarbons is accelerated
The activation period of the air pump can vary depending on engine type and operating
conditions.
Conditions for Secondary Air Pump Activation:
REQUIREMENTS
STATUS/CONDITION
M52 & M44
STATUS/CONDITION
M73
Oxygen sensor
Oxygen sensor heating
Engine coolant temperature
Engine bad
Engine speed
Fault Codes
Open Loop
Active
-10 to 40ºC*
Predefined Range
Predefined Range
No Secondary Air Faults
“currently present”
Open Loop
Active
-10 to 40ºC* Stage
Predefined Range
Predefined Range
No Secondary Air Faults
“currently present”
*NOTE: Below -10°C the air injection pump is activated only as a preventive measure to
blow out any accumulated water vapor that could freeze in the system.
33
Engine Management Systems
The Secondary Air Injection System is monitored via the use of the pre-catalyst oxygen sensor(s). Once the air pump is active and is air injected into the system the signal at the oxygen sensor will reflect a lean condition. If the oxygen sensor signal does not change within a predefined time a fault will be set and identify the faulty bank(s). If after completing the
next cold start and a fault is again present the "Check Engine" light will be illuminated.
Example: Secondary Air Injection Monitoring (Siemens System)
During a cold start condition air is immediately injected into the exhaust manifold and since
the oxygen sensors are in open loop at this time the voltage at the pre catalyst sensor will
reflect a lean condition) and will remain at this level while the air pump is in operation. Once
the pump is deactivated the voltage will change to a rich condition until the system goes
into closed loop operation.
System Operation:
The pump draws air through its own air filter and delivers it to both exhaust manifolds
through a non-return (shutoff valve). The non-return valve is used to:
1. Control air injection into the exhaust manifold - A vacuum controlled valve will open the
passageway for air to be injected once a vacuum is applied.
2. Prevent possible backfires from traveling up the pipes and damaging the air pump when
no vacuum is applied.
The control module activates the vacuum vent valve whenever the air pump is energized.
Once the vacuum vent valve is energized a vacuum is applied to the non-return valve which
allows air to be injected into the exhaust manifold. A vacuum is retained in the lines, by the
use of a check valve, in order to allow the non-return valve to be immediately activated on
cold engine start up. When the vacuum/vent valve is not energized, the vacuum to the
non-return valve is removed and is vented to atmosphere.
34
Engine Management Systems
FUEL INJECTOR VALVES
The fuel injectors which are supplied by Siemens
Inject at an angle (dual cone spray pattern). The tip
of the injector is fitted with a directional angle "plate"
with dual outlets. The lower portion of the injector
body is now jacketed in metal. The ECM control of
the injectors remains unchanged from the previous
Siemens MS41.1 system.
ENGINE/VEHICLE SPEED
LIMITATION
For engine/vehicle speed limitation, the ECM will
deactivate injection for individual cylinders, allowing
a smoother limitation transition. This prevents overrev when the engine reaches maximum RPM (under
acceleration), and limits top vehicle speed (approx.
128 mph).
MS42.0
CONTROL
MODULE
35
Engine Management Systems
RZV IGNITION SYSTEM
The Siemens MS42.0 system uses a multiple spark ignition function. The purpose of multiple ignition is:
• Provide clean burning during engine start up and while idling (reducing emissions).
• This function helps to keep the spark plugs clean for longer service life (new BMW
longlife plugs).
MS42.0
CONTROL
MODULE
INTAKE
CAMSHAFT
POSITION
SENSOR
Multiple ignition is active up to an engine speed of approximately 1350 RPM (varied with
engine temperature) and up to 20 degrees after TDC.
Multiple ignition is dependent on battery voltage.
When the voltage is low, the primary current is
also lower and a longer period of time is required
to build up the magnetic field in the coil(s).
• Low battery voltage = less multiple ignitions
• High battery voltage = more multiple ignitions
The 240 ohm shunt resistor is still used on the
MS42.0 system for detecting secondary ignition
faults and diagnostic purposes.
* 1 cylinder shown
36
Engine Management Systems
RESONANCE/TURBULENCE INTAKE SYSTEM
On the M52 TU, the intake manifold is split into 2 groups of 3 (runners) which increases low
end torque. The intake manifold also has separate (internal) turbulence bores which channels air from the idle speed actuator directly to one intake valve of each cylinder (matching
bore of 5.5mm in the cylinder head).
Routing the intake air to only one intake valve causes the intake to swirl in the cylinder.
Together with the high flow rate of the intake air due to the small intake cross sections, this
results in a reduction in fluctuations and more stable combustion.
MAIN MAINIFOLD
RAM TUBE
MS-42
RESONANCE TUBE
MAGNETIC
VALVE
MDK
HFM
VACUUM
UNIT
RESONANCE
FLAP
IDLE AIR CONTROL VALVE
(ZWD)
RESONANCE MANIFOLD
CRANKCASE VENTILATION
TURBULENCE MANIFOLD
TURBULENCE BORE 0:5.5mm
37
Engine Management Systems
RESONANCE SYSTEM
The resonance system provides increased engine torque at low RPM, as well as additional power at high RPM. Both of these features are obtained by using a resonance flap (in
the intake manifold) controlled by the ECM.
During the low to mid range rpm, the resonance flap is closed. This produces a long/single intake tube for velocity, which increases engine torque.
During mid range to high rpm, the resonance flap is open. This allows the intake air to pull
through both resonance tubes, providing the air volume necessary for additional power at
the upper RPM range.
When the flap is closed , this creates another “dynamic” effect. For example, as the intake
air is flowing into cylinder #1, the intake valves will close. This creates a “roadblock” for the
in rushing air. The air flow will stop and expand back (resonance wave back pulse) with the
in rushing air to cylinder #5. The resonance “wave”, along with the intake velocity,
enhances cylinder filling.
The ECM controls a solenoid valve for resonance flap activation. At speeds below 3750
RPM, the solenoid valve is energized and vacuum supplied from an accumulator closes
the resonance flap. This channels the intake air through one resonance tube, but increases the intake velocity.
When the engine speed is greater than 4100 RPM (which varies slightly - temperature influenced), the solenoid is de-energized. The resonance flap is sprung open, allowing flow
through both resonance tubes, increasing volume.
38
Engine Management Systems
#1 Cylinder Intake Valve open
Low to Mid Range RPM
(<3750 RPM)
#1 Cylinder Intake Valve closes
#5 Intake Valve Opens
=> Intake Air Bounce Effect
Low to Mid Range RPM
(<3750 RPM)
39
Engine Management Systems
#1 Cylinder Intake Valve open Intake air drawn from both
resonance tubes.
Mid to High Range RPM
(>3750 RPM)
#5 Cylinder Intake Valve open Intake air drawn from both
resonance tubes.
Mid to High Range RPM
(>3750 RPM)
40
Engine Management Systems
IDLE SPEED CONTROL
The ECM determines idle speed by controlling an idle speed actuator (dual winding rotary
actuator) ZWD 5.
The basic functions of the idle speed control are:
• Control the initial air quantity
(at air temperatures <0 C,
the MDK is simultaneously
opened)
MAIN MAINIFOLD
RAM TUBE
MS-42
RESONANCE TUBE
MAGNETIC
VALVE
• Variable preset idle based on
load and inputs
MDK
HFM
VACUUM
UNIT
• Monitor RPM feedback for
each preset position
RESONANCE
FLAP
• Lower RPM range intake air
flow (even while driving)
IDLE AIR CONTROL VALVE
(ZWD)
RESONANCE MANIFOLD
CRANKCASE VENTILATION
TURBULENCE MANIFOLD
• Vacuum limitation
TURBULENCE BORE 0:5.5mm
• Smooth out the transition from acceleration to deceleration
Idle speeds will vary (idle speed stabilization):
• During the warm up phase
• When Air conditioning is activated
• When a drive gear is selected
• When heating the passenger compartment
• At all electric fan speeds
• If nominal RPM is modified (idle speed increase) by
DIS service function (if applicable)
Emergency Operation of Idle Speed Actuator:
If a fault is detected with the idle speed actuator, the ECM will initiate fail-safe measures
depending on the effect of the fault (increased air flow or decreased air flow).
If there is a fault in the idle speed actuator/circuit, the MDK will compensate to maintain idle
speed. The EML lamp will be illuminated to inform the driver of a fault.
If the fault causes increased air flow (actuator failed open), VANOS and Knock Control are
deactivated which noticeably reduces engine performance.
41
Engine Management Systems
CRUISE CONTROL
Cruise control is integrated into the ECM because of the MDK operation.
Cruise control functions are activated directly by the multifunction steering wheel to the
ECM. The individual buttons are digitally encoded in the MFL switch and is input to the ECM
over a serial data wire.
The ECM controls vehicle speed by activation of the Motor Driven Throttle Valve (MDK)
The clutch switch disengages cruise control to prevent over-rev during gear changes.
The brake light switch and the brake light test switch are input to the ECM to disengage
cruise control as well as fault recognition during engine operation of the MDK.
Road speed is input to the ECM for cruise control as well as ASC/MSR regulation. The vehicle speed signal for normal engine operation is supplied from the ABS module (right rear
wheel speed sensor). The road speed signal for cruise control is supplied from the ABS
module. This is an average taken from both front wheel speed sensors, supplied via the
CAN bus.
42
Engine Management Systems
INTAKE (VACUUM) JET PUMP
The intake jet pump function is controlled by the MS42 ECM. The purpose is to provide sufficient vacuum for the brake booster in all operating conditions.
The additional vacuum compensation is activated by the ECM when the idle speed actuator is regulated for:
• A/C compressor "ON"
• Drive gear engaged (if the transmissions in fail-safe, the jet pump will always be operating)
• Engine warm up <70ºC
The ECM controls the Intake Jet Pump by activating the Solenoid Control Valve. Additional
Vacuum Enhancement is applied to the brake booster when the control circuit is "deactivated" (solenoid sprung open). Vacuum Enhancement is limited to the brake booster when
the control circuit is "activated" (solenoid powered closed).
43
Engine Management Systems
PURGE VALVE
The purge valve (TEV) is activated at 10 Hz by the ECM to cycle open, and is sprung
closed. The valve is physically different, but purge control functions are the same as the previous Siemens MS41.1 system.
VAPORS TO INTAKE
MANIFOLD
44
Engine Management Systems
TORQUE INTERFACES
If torque reduction or increase is required for ASC/DSC/MSR/AGS, the ECM will regulate
engine power in the following manner:
• If less torque is required, the ignition timing is reduced (fast intervention), the idle speed
actuator and MDK reduce intake air.
• If increased torque is required (MSR), the idle speed actuator and MDK increase intake
air.
The data required for engine torque manipulation is relayed via the CAN bus.
45
Engine Management Systems
LEAKAGE DIAGNOSIS PUMP (LDP)
The location of the LDP and charcoal canister have changed. This combination assembly
is located under the right rear trunk floor.
EVAPORATIVE FUEL SYSTEM PRESSURE LEAK DIAGNOSIS MS42.0
The LDP is capable of detecting a leak as small as 0.5 mm.
The LDP is a unitized component that contains the following:
•
•
•
•
Vacuum chamber
Pneumatic pump chamber
DME activated vacuum solenoid
Reed switch providing a switched voltage feedback signal to the DME
The LDP assembly is only replaceable as a complete unitized component, however, it is
separate from the charcoal canister.
* Location - under right rear trunk floor
46
Engine Management Systems
LDP OPERATION
During every engine cold start, the following occurs:
•
The LDP solenoid is energized by the ECM
•
Engine manifold vacuum enters the upper chamber of the LDP to lift up the spring
loaded diaphragm pulling ambient air through the filter and into the lower chamber of
the LDP through the one way valve.
MS42.0
CONTROL
MODULE
•
The solenoid is then de-energized, spring pressure closes the vacuum port blocking the
engine vacuum and simultaneously opens the vent port to the balance tube which
releases the captive vacuum in the upper chamber.
•
This allows the compressed spring to push the diaphragm down, starting the “limited
down stroke”.
47
Engine Management Systems
•
The air that was drawn into the lower chamber of the LDP during the upstroke is forced
out of the lower chamber and into the evaporative system.
•
This electrically controlled repetitive up/down stroke is cycled repeatedly building up a
total pressure of approximately +25mb in the evaporative system.
MS42.0
CONTROL
MODULE
•
After sufficient pressure has built up (LDP and its cycling is calibrated to the vehicle), the
leak diagnosis begins and lasts about 100 seconds.
•
The upper chamber contains an integrated reed switch that produces a switched highlow voltage signal that is monitored by the ECM. The switch is opened by the magnetic
interruption of the metal rod connected to the diaphragm when in the diaphragm is in
the top dead center position.
•
The repetitive up/down stroke is confirmation to the ECM that the valve is functioning.
48
Engine Management Systems
The ECM also monitors the length of time it takes for the reed switch to open, which is
opposed by pressure under the diaphragm in the lower chamber. The LDP is still cycled,
but at a frequency that depends upon the rate of pressure loss in the lower chamber.
•
If the pumping frequency is below parameters, there is no leak present.
•
If the pumping frequency is above parameters, this indicates sufficient pressure can not
build up in the lower chamber and evaporative system, indicating a leak.
MS42.0
CONTROL
MODULE
A fault code can be recorded by each ECM indicating an evaporative system leak. Upon
test completion, the ECM releases the ground path to the LDP and the internal spring pushes the diaphragm for the “full down stroke”.
At bottom dead center, the diaphragm rod opens the canister vent valve. This allows for
fresh air intake from the filter for normal purge system operation.
The LDP is diagnosable with the DIS including a service function activation test.
49
Engine Management Systems
The chart represents the diagnostic leak testing time frame in seconds. When the ignition
is switched on, the ECM performs a “static check” of circuit integrity to the LDP pump
including the reed switch.
•
On cold engine start up, the pump is activated for the first 27 seconds at
approximately 1.6 - 2.0 Hz. This pumping phase is required to pressurize the
evaporative components.
•
Once pressurized, the build up phase then continues from 27-38 seconds. The ECM
monitors the system through the reed switch to verify that pressure has stabilized.
•
The measuring phase for leak diagnosis lasts from 38-63 seconds. The pump is activated but due to the pressure build up under the diaphragm, the pump moves slower.
If the pump moves quickly, this indicates a lack of pressure or a leak. This registers as
a fault in the ECM’s.
•
From 63-100 seconds the pump is deactivated, allowing full down stroke of the
diaphragm and rod. At the extreme bottom of rod travel, the canister vent valve is
pushed open relieving pressure and allowing normal purge operation when needed.
50
Engine Management Systems
MOTOR DRIVEN THROTTLE VALVE
The MDK control function
has been integrated into the
ECM. The purpose is for precision throttle operation,
OBD II compliant for fault
monitoring, ASC/MSR control, and cruise control. This
integration reduces extra
control modules, wiring, and
sensors.
The MDK control function is integrated into the Siemens MS42.0 ECM. The ECM carries
this function out by regulating the engine throttle valve.
The engine throttle valve performs the following functions:
• Precision intake air control
• ASC control
• MSR control
• Cruise control
• Preset position during engine start up (if temperature is < 0ºC)
The new engine throttle valve (MDK) differs from the familiar EML in the following points:
• The accelerator pedal potentiometer (PWG) is now integrated in the MDK housing.
• A throttle cable is used to actuate the throttle potentiometers and also serves as a backup to open the throttle plate (full control) if the MDK system is in fail-safe.
51
Engine Management Systems
The throttle cable (foot pedal controlled) is connected to a pulley on the side of the MDK/
The pulley is linked by springs to one end of the throttle shaft, the MDK electric motor is
attached to the other end of the throttle shaft.
With the pulley linked by springs to the throttle shaft, this allows ASC intervention to override the driver’s set throttle position.
As the pulley and shaft are rotated, the twin potentiometers (integral in the MDK housing,
driver’s wish) are sensing the requested load. A twin potentiometer is used for back up
redundancy (fail-safe).
The MS42.0 ECM will actuate the MDK motor pulse width modulated in both directions at
a basic frequency of 600 Hz) which positions the throttle plate.
The second twin potentiometers feedback the actual throttle plate position, allowing the
ECM to verify correct throttle position. Again, twin potentiometers are used for back up
52
Engine Management Systems
MDK EMERGENCY OPERATION
If a fault is detected in the system, the following modes of operation are:
• Emergency operation 1 - Faults which do not impair safety, but which adversely affect
the functioning of the MDK.
• Emergency operation 2 - Applies when faults are encountered which might impair safe
driving operation.
• Emergency operation of idle speed actuator.
EMERGENCY OPERATION 1
• Activation of the EML warning lamp.
• MDK is deactivated, the throttle valve is opened mechanically by the springs and throttle cable.
• To maintain vehicle control, the MDK opening is compensated for by closing the idle
speed actuator and retarding the ignition (engine power reduction).
• Engine power is further limited by fuel injector cutout.
Emergency operation 1 limits the dynamic operation if one or more of the potentiometers
fail. The engine can slowly reach maximum speed with limited power. The EML light will
be illuminated to alert the driver of a fault.
EMERGENCY OPERATION 2
If another fault is encountered in addition to emergency operation 1 or if the plausibility is
affected, emergency operation 2 is activated by the ECM.
An example of plausibility fault would be that the pulley position does not match the MDK
position and the associated airflow.
Emergency operation 2 can also be initiated by simultaneously pressing both the accelerator pedal and the brake pedal, or if a fault is encountered in the brake light switch diagnosis.
53
Engine Management Systems
When in emergency 2 operation mode, there is an engine speed limitation (slightly above
idle speed) in addition to the measures for emergency operation 1.
In emergency operation 2, the engine speed is always limited to 1300 RPM if the brake is
not applied, and approximately 1000 RPM if the brake is applied.
The vehicle speed is limited to approximately 20-25 mph. The reason for limiting the vehicle speed is if the MDK is wide open, the vacuum assist is insufficient for the brakes.
The emergency operation functions are inactive when:
• Ignition is switched off, main relay is deactivated, and engine is started again
• A fault is not detected
• Brake pedal is not depressed
• The throttle valve is in the idle speed setting
FURTHER SAFETY CONCEPTS
The MDK safety concept can detect a jammed or binding throttle valve as well as a broken link spring. This fault is detected by the ECM monitoring the feedback potentiometers
from the MDK in relation to the pulse width modulation to activate the MDK motor.
Emergency operation functions if the throttle valve is jammed:
• Engine speed limitation depending on driver’s wish potentiometers and the MDK position.
• Limited vehicle speed if MDK is wide open.
• The ECM will alternate between 0 - 100% sensing ratio to “shake” the MDK loose.
In the event of a fault, the DIS or MODIC must be used to interrogate the fault memory, and
clear the fault once the proper repair has been performed.
54
Engine Management Systems
INTAKE AIR FLOW CONTROL
Under certain engine parameters, the MDK throttle control and the idle speed actuator
(ZWD) are operated simultaneously.
The ECM detects the driver’s wish from the twin potentiometers monitoring the cable/pulley position.
This value is added to the idle speed control value and the total is what the ECM uses for
MDK activation. The ECM then controls the idle speed actuator to satisfy the idle air “fill”,
in addition, the MDK will also be activated = pre-control idle air charge. Both of these
functions are utilized to maintain idle RPM.
The MDK is electrically held at the idle speed position, and all of the intake air is drawn
through the idle speed actuator. Without a load placed on the engine (<15% load), the
MDK will not open until the extreme upper RPM range.
If the engine is under load (>15%), the idle speed actuator is open and the MDK will also
open.
In the upper PWG range (approximately >60%), the MDK is switched off. The throttle
valve is opened wider exclusively by the pulley via the spring linkage.
At the full throttle position, “kickdown” is obtained by depressing the accelerator pedal
fully. This will overwind the pulley, but the spring linkage will not move the throttle plate
past 90 degrees of rotation.
NOTE: If the MDK is defective, it is replaced as a unit and is not internally serviceable.
55
Engine Management Systems
56
Engine Management Systems
MAIN MAINIFOLD
RAM TUBE
MS42.0
RESONANCE TUBE
MAGNETIC
VALVE
MDK
HFM
VACUUM
UNIT
IDLE AIR CONTROL VALVE
(ZWD)
RESONANCE MANIFOLD
TURBULENCE MANIFOLD
TURBULENCE BORE 0:5.5mm
Subject
Page
Leakage Diagnosis Pump (LDP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Motor Driven Throttle Valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Intake Air Flow Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
SIEMENS MS 43.0 ENGINE CONTROL SYSTEM. . . . . . . . . . . . . . . . . . . . . .57
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
MS 43.0 New Functions
Electronic Throttle Control (EML). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Accelerator Pedal Sensor (PWG). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Electronic Throttle Valve (EDK). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
Main Relay Monitor. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Engine Optimized ignition Key Off. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Diagnosis Module Tank Leakage (DM-TL). . . . . . . . . . . . . . . . . . . . . . . . 67
DM-TL Function. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .69
DM-TL Test Procedure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
SIEMENS MS 43.0 ENGINE CONTROL SYSTEM
Model: E46 equipped with M54 Engine
Production Dates: M54 B30: from 6/00, M54 B25: from 9/00
Objectives
After completing this module you should be able to:
• Identify the changes that have occurred to the MS 43 system compared to the MS 42.
• Describe the operation DMTL fuel system leakage pump.
• Describe the operation of the electronic throttle motor.
• Discuss which new components/subsystems relate directly to ULEV compliancy.
57
Engine Management Systems
This new generation Siemens system is designated as MS 43.0.
Siemens MS 43.0 is a newly developed engine management system to meet the needs of
Ultra Low Emission Vehicle (ULEV) compliancy for the 3.0 liter variant, and continue with
LEV compliancy for the 2.5 liter version. This system also includes control of the Electric
Throttle Valve (EDK).
The ECM uses a pc-board dual-processor control unit in the SKE housing configuration.
The MS 43.0 ECM is flash programmable as seen with previous systems.
ECM hardware includes:
Modular plug connectors featuring 5 connectors in the SKE housing with 134 pins.
• Connector 1 = Supply voltages and grounds
• Connector 2 = Peripheral signals (oxygen
sensors, CAN, etc.)
• Connector 3 = Engine signals
• Connector 4 = Vehicle signals
• Connector 5 = Ignition signals
Special features:
• The Flash EPROM has the capability to be programmed up to 13 times.
• Once a control unit is installed and coded to a vehicle it cannot be swapped with another vehicle for diagnosing or replacement (because of EWS 3.3).
58
Engine Management Systems
SYSTEM OVERVIEW I-P-O
134 PIN
Service
Engine
Soon
59
Engine Management Systems
MS 43 NEW FUNCTIONS
ELECTRONIC THROTTLE SYSTEM - EML
The M54 engine with MS 43 engine control uses an electronic throttle control system
adopted from the ME 7.2 system on the M62 engine. The system incorporates an electric
throttle valve (EDK) and pedal position sensor (PWG) for engine power control.
The MS 43 control module monitors the PWG input and activates the EDK motor based on
the programmed maps for throttle control. The MS 43 module self checks the activation of
the EDK via feedback potentiometers motor on the EDK motor.
Additional functions of the EML system include:
• Cruise control function
• DSC throttle interventions
• Maximum engine and road speed control
60
Engine Management Systems
MS 43 NEW FUNCTIONS
ACCELERATOR PEDAL SENSOR
The accelerator pedal sensor is similar to the PWG used on the ME 7.2 system. It is integrated into the accelerator pedal housing. Two hall sensors are used to provide the driver’s
input request for power.
The hall sensors receive power (5 volts) and ground from the MS 43 control module and
produce linear voltage signals as the pedal is pressed from LL to VL.
PWG SENSOR 1 = 0.5 to 4.5 V
HS
PWG SENSOR 2 = 0.5 to 2.0 V
HS
The MS 43 control module uses the
signal from sensor 1 as the driver’s
request and the signal from sensor 2
as plausibility checking.
SIGNAL 1
SIGNAL 2
1 2
3
4
5
HALL SENSOR
POWER
MS 43.0
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
61
Engine Management Systems
MS 43 NEW FUNCTIONS
ACCELERATOR PEDAL SENSOR
PWG SIGNAL MONITORING & PWG FAILSAFE OPERATION:
•
As a redundant safety feature the PWG provides two separate signals from two integral
angle hall sensors (HS #1 and HS #2) representing the driver’s request for throttle activation.
•
If the monitored PWG signals are not plausible, MS 43.0 will only use the lower of the
two signals as the driver’s pedal request input providing failsafe operation. Throttle
response will be slower and maximum throttle position will be reduced.
•
When in PWG failsafe operation, MS 43.0 sets the EDK throttle plate and injection time
to idle (LL) whenever the brake pedal is depressed.
•
When the system is in PWG failsafe operation, the instrument cluster matrix display will
post “Engine Emergency Program” and PWG specific fault(s) will be stored in memory.
_____________________________________________________________________________
_____________________________________________________________________________
62
Engine Management Systems
MS 43 NEW FUNCTIONS
EDK THROTTLE POSITION FEEDBACK SIGNALS
The EDK throttle plate is monitored by two integrated potentiometers. The potentiometers
provide linear voltage feedback signals to the control module as the throttle plate is opened
and closed.
Feedback signal 1 provides a signal from 0.5 V (LL) to 4.5 V (VL).
Feedback signal 2 provides a signal from 4.5 V (LL) to 0.5 V (VL)
Potentiometer signal 1 is the primary feedback signal of throttle plate position and signal 2
is the plausibility cross check through the complete throttle plate movement.
63
Engine Management Systems
MS 43 NEW FUNCTIONS
EDK THROTTLE POSITION FEEDBACK SIGNALS
EDK FEEDBACK SIGNAL MONITORING & EDK FAILSAFE OPERATION:
•
The EDK provides two separate signals from two integral potentiometers (Pot 1 and Pot
2) representing the exact position of the throttle plate.
•
EDK Pot 1 provides the primary throttle plate position feedback. As a redundant safety feature, Pot 2 is continuously cross checked with Pot 1 for signal plausibility.
•
If plausibility errors are detected between Pot 1 and Pot 2, MS 43.0 will calculate the
inducted engine air mass (from HFM signal) and only utilize the potentiometer signal that
closely matches the detected intake air mass.
-
The MS 43.0 uses the air mass signalling as a “virtual potentiometer” (pot 3) for a
comparative source to provide failsafe operation.
-
If MS 43.0 cannot calculate a plausible conclusion from the monitored pots (1 or 2
and virtual 3) the EDK motor is switched off and fuel injection cut out is activated
(no failsafe operation possible).
•
The EDK is continuously monitored during all phases of engine operation. It is also
briefly activated when KL 15 is initially switched on as a “pre-drive check” to verify it’s
mechanical integrity (no binding, appropriate return spring tension, etc). This is accomplished by monitoring both the motor control amperage and the reaction speed of the
EDK feedback potentiometers. If faults are detected the EDK motor is switched off and
fuel injection cut off is activated (no failsafe operation possible). The engine does however continue to run extremely rough at idle speed.
•
When a replacement EDK is installed, the MS 43.0 adapts to the new component
(required amperage draw for motor control, feedback pot tolerance differences, etc).
This occurs immediately after the next cycle of KL 15 for approximately 30 seconds.
During this period of adaptation, the maximum opening of the throttle plate is 25%.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
64
Engine Management Systems
MS 43 NEW FUNCTIONS
MAIN RELAY MONITOR
The MS 43.0 system incorporates a new monitoring feature for terminal 87 (KL 87) of the
main relay. The relay is monitored internally for the voltage level at KL 87. Five seconds after
the ignition key is switched on, and the voltage at the KL 15 input is greater than 9 volts,
the control module checks the voltage at KL 87.
If the voltage difference between the two terminals is greater than 3 volts, a fault will be
stored in the ECM.
_____________________________________________________________________________
_____________________________________________________________________________
_____________________________________________________________________________
65
Engine Management Systems
MS 43 NEW FUNCTIONS
EMISSION OPTIMIZED - IGNITION KEY OFF
“Emission Optimized Ignition Key Off” is a programmed feature of the MS 43 DME. After
the DME detects the key being switched OFF, the ignition stays active (main relay/voltage
supply) for two more individual coil firings. This means that just two cylinders are fired - not
two revolutions.
This feature allows residual fuel, injected into the cylinders as the ignition key is switched
off, to be burned as the engine runs down.
The unloader relay, previously used in the MS 42.0 system for ignition coil KL 15 supply, is
now supplying voltage to the injection valves. The ignition coils’ KL15 voltage is provided
by the DME main relay.
When KL 15 is switched off, the DME operating voltage is removed. The DME will maintain a ground to the main relay for a few seconds to maintain ignition coil supply voltage.
66
Engine Management Systems
MS 43 NEW FUNCTIONS
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
The M54 engine with the Siemens MS43.0 engine control system uses the DMTL system
for fuel system leakage monitoring. The pump is manufactured by Bosch for use with the
Siemen’s control system.
67
Engine Management Systems
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
FUNCTIONAL OVERVIEW:
The DM-TL is located next to the charcoal canister on the E46.
1. In it’s inactive state, filtered fresh air enters the evaporative system through the sprung
open valve of the DM-TL.
2. When the DME activates the DM-TL for leak testing, it first activates only the pump
motor. This pumps air through a restrictor orifice (1.0 or 0.5 mm) which causes the electric motor to draw a specific amperage value. This value is equivalent to the size of the
restrictor.
3. The solenoid valve is then energized which seals the evap system and directs the pump
output to pressurize the evap system.
The evap system is detected as having a large leak if the amperage value is not realized, a
small leak if the same reference amperage is realized or no leak if the amperage value is
higher than the reference amperage.
1
68
Engine Management Systems
2
3
DM-TL (DIAGNOSIS MODULE - TANK LEAKAGE)
FUNCTION
The DC Motor LDP ensures accurate fuel system leak detection for leaks as small as
0.5mm (.020”). The pump contains an integral DC motor which is activated directly by the
engine control module. The ECM monitors the pump motor operating current as the measurement for detecting leaks.
The pump also contains an ECM controlled change over valve that is energized closed during a Leak Diagnosis test. The change over valve is open during all other periods of operation allowing the fuel system to “breath” through the inlet filter (similar to the full down
stroke of the current vacuum operated LDP).
69
Engine Mangement Systems
LEAK DIAGNOSIS TEST PRECONDITIONS
The ECM only initiates a leak diagnosis test every second time the criteria are met. The criteria is as follows:
•
Engine OFF with ignition switched OFF.
•
Engine Control Module still in active state or what is known as “follow up mode” (Main
Relay energized, control module and DME components online for extended period after
key off).
•
Prior to Engine/Ignition switch OFF condition, vehicle must have been driven for a minimum of 20 minutes.
•
Prior to minimum 20 minute drive, the vehicle must have been OFF for a minimum of 5
hours.
•
Fuel Tank Capacity must be between 15 and 85% (safe approximation between 1/4 3/4 of a tank).
•
Ambient Air Temperature between -7OC & 35OC (20OF & 95OF )
•
Altitude < 2500m (8,202 feet).
•
Battery Voltage between 11.5 and 14.5 Volts
When these criteria are satisfied every second time, the ECM will start the Fuel System Leak
Diagnosis Test. The test will typically be carried out once a day i.e. once after driving to
work in the morning, when driving home in the evening, the criteria are once again met but
the test is not initiated. The following morning, the test will run again.
70
Engine Management Systems
LEAK DIAGNOSIS TEST
PHASE 1 - REFERENCE MEASUREMENT
The ECM activates the pump motor. The pump pulls air from the filtered air inlet and passes it through a precise 0.5mm reference orifice in the pump assembly.
The ECM simultaneously monitors the pump motor current flow . The motor current raises
quickly and levels off (stabilizes) due to the orifice restriction. The ECM stores the stabilized
amperage value in memory. The stored amperage value is the electrical equivalent of a 0.5
mm (0.020”) leak.
71
Engine Mangement Systems
PHASE 2 - LEAK DETECTION
The ECM energizes the Change Over Valve allowing the pressurized air to enter the fuel system through the Charcoal Canister, The ECM monitors the current flow and compares it
with the stored reference measurement over a duration of time.
Once the test is concluded, the ECM stops the pump motor and immediately de-energizes
the change over valve. This allows the stored pressure to vent thorough the charcoal canister trapping hydrocarbon vapor and venting air to atmosphere through the filter.
72
Engine Management Systems
TEST RESULTS
The time duration varies between 45 & 270 seconds depending on the resulting leak diagnosis test results (developed tank pressure “amperage” / within a specific time period).
However the chart below depicts the logic used to determine fuel system leaks.
73
Engine Mangement Systems
Review Questions
1. List the components that are required to be monitored under OBD II regulations.
2. What type of faults will cause the Check Engine (MIL) lamp to illuminate immediatly?
In most situations how many times must a fault be registered before the light will
come on?
3. What occured to the 20 pin diagnostic connector after 6/00 production?
4. Describe the signal produced by the camshaft position sensors. What does the ECM
use this information for? What would be the result if one of the sensors failed? Why?
5. What is the reason that the crankshaft position sensor is mounted in the crankcase?
6. What input would inform the ECM that the coolant returning from the radiator is too
hot? What output control does the ECM have to assist in cooling the engine?
7. Explain how the ignition coils are controlled in the MS 42.0 and MS 43.0 system.
74
Engine Management Systems
8. How is the idle valve bypass air channeled to the intake valves?
9. How many CAN lines are present at the ECM? Why?
10. How does the LDP pump help the MS 42.0 ECM determine that the fuel tank is free of
leaks? Compare this to the operation of the DMTL in the MS 43.0.
11. On an engine using an MDK, where is the PWG signal produced? What is the purpose
of the throttle cable?
12. What type of signal is produced by the PWG Hall sensors used in the MS43.0 system?
What is the result if one of those signals is not received by the ECM?
75
Engine Management Systems
Table of Contents
AUTOMATIC TRANSMISSIONS
Subject
Page
A5S 360R GM 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
System and Components Overview
Components
Case and Pan . . . . . . . . . . . . . . . .
Torque Converter . . . . . . . . . . . . . .
Vane Pump . . . . . . . . . . . . . . . . . .
Electro/Hydraulic Valve Body . . . . .
Accumulator Chambers . . . . . . . . .
Multi plate Drive and Brake Clutches
Free Wheel Clutches . . . . . . . . . . .
Planetary Gearset . . . . . . . . . . . . .
Transmission Fluid Heat Exchanger .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.6
.6
.7
.8
.9
10
11
12
14
A5S 360R Power Flow . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
GS 20 Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
GS 20 IPO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
GS 20 Input Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
GS 20 Output Control Signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
CAN Bus Communication . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
GS 20 Program Features Overview
AGS (Adaptive Transmission Control)
Non AGS Functions . . . . . . . . . . . . .
Adaptive Hydraulic Pressure Control .
Emergency Program . . . . . . . . . . . .
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
.
22
22
25
26
Service Information
Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Checking Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Service & Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Subject
Page
Diagnosis & Programming
Fault Codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Basic Troublshooting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
A5S 325Z 5HP 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
Converter Clutch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Oil Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Clutches. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Transmission Diagram. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Planetary Gear Set. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
Oil Pan. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Transmission Weight. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Position of Selector lever and Steptronic Function. . . . . . . . . . . . . . . . . . 43
Modifications to Electro-hydraulic Control System. . . . . . . . . . . . . . . . . . 43
Solenoid Valve and Clutch Logic. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
Electronic Control Unit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .46
Recording Turbine Speed. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Programming. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
Modifications to the Adaptive Transmission Control. . . . . . . . . . . . . . . . . 50
System Overview with Steptronic for E46. . . . . . . . . . . . . . . . . . . . . . . . 51
Service Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
Transmission Application Chart. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
A5S 360R GM 5
Model: E46 All Versions
Production Dates: 323i/Ci/Cic : 6/98 to 3/00, 323it: 1/00 to 3/01,
328i/Ci/Cic: 6/98 to 6/00, 330Xi: from 6/00,
325Xi: from 9/00
Objectives
After completing this module you should be able to:
•
List the electronic solenoids used in the valve body of the transmission.
•
Explain the purpose of the accumulator chambers.
•
Describe the installed location and operation of the range selector switch.
•
Identify the communication between the AGS and other modules in the vehicle.
•
Describe the features of the AGS driving programs.
•
Recognize the symptoms of a vehicle in the transmission emergency program.
•
Know how to check and fill the transmission fluid.
•
Understand the scope of repairs possible on the A5S 360R transmission.
INTRODUCTION
The E46 introduces a new 5 speed automatic transmission manufactured by General
Motors Powertrain division of Strasbourg, France. The transmission is designated:
•
•
A5S 360R - BMW Designation
5 L40-E: GM Designation
The transmission will be available as an option in both the 323i and 328i models from start
of production. The A5S 360R will also be available in the 1999 528i (9/98 production).
SYSTEM OVERVIEW
The A5S 360R transmission offers the following features and benefits:
•
The A5S 360R’s has a maximum torque rating of 360Nm.
•
Designed and manufactured to provide maintenance free lifetime operation,
•
Transmission fluid is designated as “sealed for life”.
•
Gradual torque converter lock up providing a controlled degree of clutch slippage and
smooth transition to full lock.
•
Torque converter variable lock up control can occur in 3rd, 4th and 5th gears.
•
New GS 20 control system designed and manufactured via a joint effort with BMW,
Siemens and GM.
•
AGS shift program logic controlled,
•
Transmission diagnostics improved due to the new E46 diagnostic concept,
•
Drivetrain management system communication via CAN
• Emergency Program (Safety Mode) activates if certain faults are present
4
Automatic Transmissions
OVERVIEW OF COMPONENTS
The A5S 360R is an assembly of the following:
•
Four case housing design (Torque converter bell housing, pump cover plate, main and
extension cases)
•
Single piece sump pan
•
Replaceable oil filter unit
•
Four element torque converter assembly with variably controlled lock up clutch.
•
Vane type oil pump.
•
Four multi-plate drive clutches with single sided friction plates
•
Five multi-plate brake clutches with single sided friction plates,
•
Four Free Wheel One Way Clutches (sprag type)
FW1
CD
CC1
CR
FW3
C1
COD
FW4
CI
FW2
LBC
CC2
C2
•
One Planetary Gearset Assembly
•
One Valve Body with solenoids for pressure regulation, shift control, torque converter
regulated lock up and reverse lock out (combined function).
5
Automatic Transmissions
COMPONENTS
Transmission Cases and Pan:
Made of aluminum alloy, the cases are light weight. The single piece oil pan is made of single wall sheet metal. It includes a drain plug on the bottom surface at the rear .
The oil pan is mounted to the main case by 20 bolts. Oil pan sealing integrity is ensured
by a controlled compression gasket. Cross tightening is required to ensure an even seal.
Final torque of pan bolts is 10-12 Nm.
Torque Converter:
The 4 element torque converter consists of the Turbine, Rotor,
Stator with one way clutch and Lock up clutch. Similar in
function to previous torque converters, this unit’s lock up
clutch is:
•
•
•
Fully disengaged
Variable engagement providing precise slippage,
Fully engaged (locked)
The various clutch application hydraulic pressures are regulated by the control module activated torque converter lock up
solenoid.
The torque converter is manufactured specifically for the
model it is installed in and is part number specific.
6
Automatic Transmissions
Vane Pump:
The A5S 360R uses a vane pump to provide the transmission main line oil supply for operation and cooling requirements. The pump rotor is mechanically driven by the torque converter oil pump drive tangs at 1:1 engine speed rotation providing pump operation.
PIVOT PIN
SLIDE
The rotor with 13 vanes is located in a recess on
the rear surface of the bell housing covered by the
pump cover plate. The rotor and vanes are
placed inside a slide mechanism. As the rotor
spins, the vanes “sweep” the oil from the pump
intake to the output along the mating surface of
the vane ends and the interior surface of the slide.
The slide is mounted on a pivot pin. As it pivots, it
changes the eccentricity of the rotor to slide mating
surface changing the pump output volume.
ROTOR &
VANES
CALIBRATED SPRING
The slide’s position is influenced by a calibrated
spring and hydraulic input pressure from the main
pressure regulator solenoid in the valve body.
The benefit of changing the slide position is to optimize pump output volume to meet the
needs of the operating conditions.
•
Max volume during
engine startup. This
condition provides a
fast priming action
of the pump for
immediate lubrication and hydraulic
pressure for operation.
•
Regulated output
volume for varied
driving conditions.
Maximum volume is
not required at all
times.
The GS 20 regulates the pump output volume as well as main line pressure regulation
7
Automatic Transmissions
Electro/Hydraulic Valve Body:
Located in the oil sump, the valve body is the electro/hydraulic control center for regulating
and distributing pressurized transmission fluid for activating the various clutches, torque
converter variable lock up, and regulation of main line oil pressures.
Sub components of the valve body assembly include:
•
Manual valve
•
One main pressure regulator solenoid (Pressure Regulator Force Motor Solenoid - "GM
term")
•
One torque converter regulator solenoid (also serves the Reverse Lock out function)
•
Three MV shift solenoids (When activated in a coded sequence provide shifts for 1-2,23,3-4,4-5)
•
The spool valves and springs for controlling apply pressures, activating shifts, regulating torque converter lock up, etc.
•
Four accumulator chambers for "cushioning" the transmission fluid apply pressure during upshifts 1-2, 2-3, 3-4, 4-5.
TORQUE CONVERTER
LOCKUP REGULATOR
SOLENOID
MANUAL VALVE
SHIFT
VALVE
"C"
SHIFT
VALVE
"B"
SHIFT
VALVE
"A"
MAIN PRESSURE REGULATOR
8
Automatic Transmissions
ACCUMULATORS
DO NOT REMOVE THESE
TWO SCREWS WHEN REMOVING
VALVE BODY FROM TRANSMISSION
Accumulator Chambers:
The accumulator chambers are similar in function to "fluid dampers". The accumulators are
used to improve shift quality by absorbing apply pressures on the multiplate clutches providing a cushioned clutch engagement.
Clutch apply fluid pressure
directed to an accumulator
piston and helped by a
spring force opposes an
accumulator fluid line pressure creating an action
similar
to
a
shock
absorber.
BLEED
LINE PRESSURE
FROM OIL PUMP
NO PRESSURE
FROM SHIFT VALVE
The apply pressure pushes the clutch piston
against the steel/friction plates causing initial engagement.
NO PRESSURE
TO CLUTCH
Once the clearance between the clutch plates is taken up by the piston travel and the
plates begin complete engagement the fluid pressure builds very rapidly.
The accumulator is connected to the clutch
apply circuit which at this
point starts to absorb the LINE PRESSURE
FROM OIL PUMP
rapidly building pressure.
BLEED
APPLY PRESSURE
FROM SHIFT VALVE
The accumulator piston
moves upward accommodating the high pressure
fluid causing a delayed
complete engagement.
SOFTENED APPLY
PRESSURE TO CLUTCH
9
Automatic Transmissions
Multi plate Drive and Brake Clutches:
Located in the main case are four drive
and five brake clutches. When cushioned hydraulic control pressure is
applied, the clutches engage smoothly
with a slight delay.
CLUTCH HOUSING
FRICTION DISC
CLUTCH HUB
APPLY PISTON
The valve body activates the various
drive and brake clutches in a coded
sequence to transmit engine drive
torque to the planetary gear set providing the various output shaft ratios.
OIL PASSAGE
The clutches are multiplate units with
both steel and friction plates. The friction plates are single sided.
RELEASE SPRING
INPUT SHAFT
CLUTCH RELEASED
CLUTCH
HOUSING
CLUTCH DISCS SEPERATED
APPLY
PISTON
OIL PASSAGE
CLUTCH APPLIED
ALL CLUTCH DISCS FORCED TOGETHER
OIL FORCES
PISTON TO
APPLY CLUTCH
10
Automatic Transmissions
PRESSURIZED OIL FOR APPLY
STEEL DISC
Free Wheel Clutches (Sprag Type):
Free wheel clutches spin freely in one
direction and lock in the opposite
direction.
SPRAGS
They consist of an inner race, an
outer race and the sprag assembly.
The sprag assembly contains individual, asymmetrically shaped wedges
(sprags).
•
•
When the inner race is driven, the
sprags allow free wheel rotation.
There is no effect on the outer
race.
END BEARING
RETAINER RING
When the outer race is driven, the
(OUTER RACE)
sprags wedge between the inner SPRAG RACE ASSEMBLY
and outer races causing them to
lock. The inner race is then driven
by the outer race.
A
Free wheel clutches are used to:
B
•
hold components stationary,
•
drive components when driven
•
SPRAG CAGE
free wheel, allowing power to spin ASSEMBLY
the inner or outer race without an
output reaction.
(INNER RACE)
INPUT SUN GEAR
The A5S 360R utilizes four Free Wheel clutches to perform various shifting and component
holding functions during the delayed, cushioned multi plate clutch engagement preventing
an interruption in the power flow during upshifts.
The clutches are identified as FW1, FW2, FW3 and FW4.
11
Automatic Transmissions
Planetary Gearset (Ravigneaux)
Based on the Ravigneaux design, the A5S 360R planetary gearset is made up of two sections; front & rear. It functions as a single integral assembly with a common planetary carrier and a set of common long planetary gears. It consists of the following components:
•
•
•
•
•
•
Two separate ring gears,
Two separate input sun gears (one front, one rear)
One set of three long planetary gears common to both sections (front-rear).
One set of three short planetary gears (rear)
One set of three short planetary gears (front)
One common planetary carrier.
The gearset has three possible torque inputs:
1. Planetary carrier
2. Front input sun gear
3. Rear input sun gear
Three possible reaction components:
1. Planetary carrier
2. Front ring gear
3. Front input sun gear
and one torque output:
1. Rear ring gear.
Planetary Gearset “Input - Reaction - Output” Chart
Gear
Input
Reaction
Output
Ratio
First
Rear Input Sun Gear
Planetary Carrier
Rear Ring Gear
3.45:1
Second
Rear Input Sun Gear
Front Ring Gear
Rear Ring Gear
2.21:1
Third
Rear Input Sun Gear
Front Input Sun Gear
Rear Ring Gear
1.59:1
Fourth
Rear Input Sun Gear
& Planetary Carrier
None
Rear Ring Gear
1.00:1
Fifth
Planetary Carrier
Front Input Sun
Rear Ring Gear
0,76:1
12
Automatic Transmissions
LONG PINION
FRONT INPUT SUN
REAR INPUT SUN
FRONT SHORT PINION
REAR SHORT
PINION
RING GEAR FRONT
RING GEAR REAR
FRONT VIEW
REAR VIEW
REAR PLANETARY PINION
(SHORT)
RING GEAR FRONT
PLANETARY CARRIER
FRONT PLANETARY PINION
(SHORT)
PLANETARY PINION
(LONG)
INPUT SUN FRONT
INPUT SUN REAR
OUTPUT SHAFT GEAR
13
Automatic Transmissions
Transmission Fluid Heat Exchanger:
A transmission fluid heat exchanger is
located on the bottom edge of the radiator.
Transmission fluid inlet and outlet hose
fittings are located on the driver’s side of
the transmission.
The heat exchanger provides two functions:
•
After initial start up, the transmission
fluid is warmed up by the engine
coolant as it passes through the heat
exchanger. The heat exchanger is
controlled by an integral thermostat
which regulates the transmission fluid
flow into the radiator exchanger. In
this state the heat exchanger acts as
a transmission oil heater.
•
During operation at higher temperatures, the hot transmission fluid loses heat to the
engine coolant when it passes through the heat exchanger and into the core of the radiator.
14
Automatic Transmissions
A5S 360R POWER FLOW
The GS 20 module controls the hydraulic valve body through electrical activation of the various solenoids. Electrical activation is based on a programmed operation map and transmission operating conditions (vehicle speed, engine load, throttle position, range selection,
AGS program logic, etc).
Engine torque is transferred by the various drive clutches when activated. The various
torque paths enter the planetary gearset as input. Simultaneously, the planetary gearset
is provided with reactionary input (held components) from the various brake clutches and
Free Wheel clutches.
The output result is five forward drive gears with progressive ratios and a single reverse
gear.
TORQUE CONVERTER
LOCK UP CLUTCH
TORQUE
CONVERTER
CI COD
LBC C2 CC2
TRANSMISSION CASE
CC1
C1
CD
CR
FRONT RING
FW4
REAR RING
SMALL
FRONT
PLANET
FW2
PLANETARY
CARRIER
LARGE COMMON
PLANET GEAR
FW3
FRONT INPUT SUN
PUMP
SMALL
REAR
PLANET
FW1
ONE WAY
CLUTCH
REAR INPUT SUN
INPUT
Range
OUTPUT
Gear Ratio
Clutches
Free Wheels
C1 C2 CI CD COD CC1 LBC CC2 CR
D/4/3/2
1
3.45:1
X
X
2
2.21:1
X
X
D/4/3
3
1.59:1
X
X
X
D/4
4
1.00:1
X
X
X
X
D
5
0.76:1
X
X
X
X
P/N
/
/
X
X
X
X
1
2
3
X
X
X X
X
X
X
X
X
Solenoids
4
A
B
C
X
TCC
OFF
ON
ON
NO
ON
ON
ON
NO
ON
OFF
ON
Y/N
OFF
OFF ON
Y/N
OFF
OFF OFF
Y/N
OFF
ON
OFF
15
Automatic Transmissions
TRANSMISSION CONTROL SYSTEM (GS 20)
The A5S 360R automatic transmission is
controlled by the GS 20 control module.
The acronym (GS) comes from the German
word "Getriebesteurung", meaning
Gearbox Control.
GS 20
CONTROL
The design, program development and
manufacturing of the GS 20 control system
is the result of the combined efforts of
BMW, Siemens and GM.
The GS 20 control module is located in the
E box in the engine compartment. It utilizes
the 134 pin, "SKE" (standard shell construction), modular connector, enclosure.
BMW PRODUCTION LINE LABEL
IDENTIFICATION LABEL:
•
•
•
•
•
•
•
BMW Part Number
Version Identification
Software Level
Production Date
Serial Number
Siemens Part Number
GM Part Number
Its blue connector color designates it a Transmission Control Module. The GS 20 utilizes 3
of the 5 modular connectors.
Connector 1: (X70001) 9 pins
= Power and ground connections.
Connector 4: X70004, 40 pins = Input and output control signal connections to transmission components in
the transmission and CAN to MS 42.0.
Connector 3: (X70003) uses 26 of the 52 pins = Input and output control signal connections to
components in interior compartment (shift lock, EWS interface, brake light switch).
16
Automatic Transmissions
ENGINE CONTROL POWER KL 87
BACK UP LIGHTS
CONTROL RELAY
TCM
(GS 20)
TO BACK UP LIGHTS
& REVERSE SIGNAL
(PDC, NAV, Electrochromatic rearview mirror)
SHIFT LOCK
KICK DOWN
MK20
EI
MS42
CAN
BRAKE LIGHT
SWITCH
BRAKE TEST
SWITCH
P/N SIGNAL
TO EWS 3.3
20
SHIFT VALVE "A" (MV1)
10
SHIFT VALVE "B" (MV2)
9
SHIFT VALVE "C" (MV3)
3
VALVE BODY POWER
HSD2
MoD
iC
DIAGNOSIS &
PROGRAMMING
DIS
MoDiC
+
RANGE
SELECTION
SWITCH
TC LOCK UP
REGULATOR
SUPPLY
+
TRANS.
INPUT
SPEED
C
6
S
11
8
B
VALVE BODY
A
MAIN
PRESSURE
REGUALTOR
TRANS.
OIL TEMP.
TRANS.
OUTPUT
SPEED
S
17
Automatic Transmissions
GS 20 INPUT SIGNALS
Power Supply and Grounds:
The GS 20 receives:
•
•
•
•
KL 30 (constant battery power),
KL 15 (terminal 15 of the ignition switch)
KL 87 (operating power from the Engine Control Main Relay)
KL 31 (ground connection for the control module electronics and peripheral component
operation)
The GS 20 monitors the power/ground inputs for shorts (B+ and B-), open circuits and battery voltage levels (high and low).
Range Selector Switch:
The switch is mounted inside the transmission main case on the driver’s side. This location provides precise monitoring of the Manual
valve position and is sheltered from the harsh environment under the
vehicle external of the main case. Adjustment is not required.
The range selector switch has 6 wires. The GS 20 provides the switch with 12 volts on one
wire (pin 2 of connector X70004).
X70004
Depending on the range selector posi- Park
tion, the switch provides coded high Reverse
signals over five wires to the GS 20. Neutral
The addition of the fifth wire (pin 1) is Drive
4
new compared with previous four wire
3
range selectors providing a redundant
2
P/N signal circuit.
Pin 1
X
Pin 14
X
X
X
X
X
Pin 15
X
X
X
X
Pin 16
Pin 17
X
X
X
X
X
X
X
X
X = High Signal
Electronic Brake and Brake Test Switch:
The GS 20 monitors the brake pedal position to activate sport mode, down hill recognition
and for the shift lock operation. The control module receives both the brake and brake test
hall effect sensor signals. When pressed;
· the brake light switch pulls a standing voltage in the GS 20 low,
· the brake test switch provides a high signal to a circuit monitor in the GS 20.
18
Automatic Transmissions
Kick Down Switch:
When the throttle pedal is pressed fully to
the floor, the kick down switch closes providing a ground signal to the GS 20.
The GS 20 recognizes the ground as a
request to provide an immediate down shift
and to switch to the AGS sport mode shifting program.
Transmission Fluid Temperature Sensor:
Located in the transmission oil sump, the NTC oil temperature sensor’s
ohmic value decreases as the temperature increases. The GS 20 monitors
the fluid temperature by sensing the voltage drop across the sensor causing a standing monitor voltage to "bleed" to ground. Rise and fall of the
standing voltage value is a direct correlation of the fluid temperature.
Detection of high fluid temperature modifies the torque converter regulation control and
modifies the shift program to aid in reducing transmission fluid temperature.
If the signal becomes impaired, the GS 20 applies a substitute temperature value based on
Engine Temperature via CAN and stores a specific fault code.
Transmission Input and Output Speed Sensors:
The transmission speed sensors (turbine and output shaft) are analog inductive sensors that produce an AC sine wave similar to an ABS/ASC wheel
speed sensor. The AC signal frequency is proportional to the rotation speed
of the monitored components .
•
The turbine speed sensor scans a pulse wheel attached to the forward clutch housing.
•
The output shaft speed sensor scans a pulse wheel attached to the rear ring gear.
The GS 20 monitors these signals along with the engine speed signal (CAN) to calculate
transmission slip ratio for plausibility and for the adaptive pressure control function.
The sensors are monitored for plausible signals, opens and shorts. Specific fault codes are
stored for defects with these sensors.
19
Automatic Transmissions
GS 20 OUTPUT CONTROL SIGNALS
Valve Body Solenoid and Pressure Regulator Control
The GS 20 activates the 3 shift solenoids by individual switched
ground output control signals.
The Main Oil Pressure and Torque Converter Lock up regulators are
controlled by a Pulse Width Modulated (PWM) control to ground.
PWM control modulates the hydraulic control pressures based on the
current AGS shift program and maintains adaptive pressure control.
Shift Lock Solenoid Control:
The shift lock feature prevents the unintentional movement of the shifter from Park or
Neutral.
When KL 15 is switched on, the shift lock is
engaged, when the brake pedal is pressed,
the GS 20 releases the ground control circuit of the shift lock solenoid unlocking the
shift gate. Additionally, above 2500 RPM,
the selector lever remains locked in Park
even if the brake pedal is applied.
P/N Signal:
As an output function, the GS 20 provides the EWS 3.3 with a switched high/low signal for
P/N status.
•
•
P or N = high
all other ranges = low.
The EWS 3.3 provides the P/N safety feature preventing the starter motor from operating
unless the shifter is in P/N (high signal).
Back Up Light Relay Control:
As an output function, the GS 20 provides a switched ground to activate the control circuit
of the back up light relay when the range selector is in R. The Back Up Light Relay provides power directly to the back up lights. The lighting circuit is also used as a high signal
indicating Reverse status for PDC, NAV and the electro chromatic rearview mirror systems.
20
Automatic Transmissions
CAN BUS COMMUNICATION:
The E46 utilizes the now familiar “twisted pair” CAN bus wiring configuration for drivetrain
and instrument cluster communication interface. The MS 42.0 to GS 20 link is a dedicated CAN circuit. The MS 42.0 is the gateway for data exchange between the GS 20 and
Mark 20 EI (traction control) and the Instrument cluster.
80
100
12
0
20
2
120 140
160
180
80
60
4
5
1/min
x1000
120
6
1
200
40
11
3
100
60
40
220
240
20
UNLEADED GASOLINE ONLY
km/h
140
0
50 30 20 15
7
12
MPH
CAN bus data exchange for the GS 20
includes:
•
•
•
•
•
•
•
•
•
•
•
•
Engine Speed (input),
Engine Temperature (input),
Accelerator pedal position and rate of
application (input),
Engine intervention signalling (input and
output)
Shift delay for traction control and warm
up phase (input)
Active shift program (output)
Cruise control requirements (input)
Turn recognition (input)
Current Range and program selection (output)
Torque Converter lock up signalling (output)
Transmission fault indication lamp (output)
etc..
21
Automatic Transmissions
GS 20 Program Features Overview
AGS (ADAPTIVE TRANSMISSION CONTROL)
The GS 20 adaptive transmission control feature automatically selects suitable shifting programs based on driving style, selected range, monitored signal activity and road/environmental conditions. Advantages to the AGS shift control include:
•
•
•
•
Shift points adapted to the driving style
Improved safety - no unwanted up shifting while in a tight curve,
Automatic determination and selection of the winter program for better driveaway traction and reduced shift activity.
Improved comfort - Starting in second gear in stop and go traffic.
The AGS can be divided into two functional groups:
1. Driver influenced features
2. Features that react automatically to the driving style and environmental conditions.
DRIVER INFLUENCED FEATURES OF AGS
The adaptive drive program is based primarily on throttle input from the MS 42.0 control
module via the CAN bus. The calculated rate of pedal position change influences the selection of the shift points.
Moderate movement
causes moderate
downshifts while a
quick application of
the throttle initiates a
downshift.
The GS 20 also
monitors braking
and kickdown
request.
Economical driving: Shifter in D. Drive with slow application of throttle. This provides low
and comfortable shift points providing high fuel efficiency.
Quick accelerator pedal activity automatically leads the GS 20 into the intermediate power
mode. Based on this input data, the AGS automatically selects a sporty shift strategy.
Sport: Shifter in "D", shift points are higher to take advantage of the full engine performance. The sport program is also immediately activated by a kick down request or excessive braking.
22
Automatic Transmissions
The AGS driving programs are not adapted on a long term basis - nor is it stored
in the GS 20 control module memory when the ignition key is switched off.
The GS 20 continuously monitors the driving style and adapts to meet the current
driver requirements.
AGS FEATURES THAT REACT TO OPERATING CONDITIONS
Stop and Go Driving: This feature is activated by a defined sequence of shifts which are
as follows:
•
Upshift from first to second - followed by a downshift from second to first - followed by
another upshift from first to second. This is then followed by the vehicle coming to a
complete stop.
After this sequence, the transmission will stay in second gear. The GS 20 AGS program
has recognized stop and go driving and this function prevents excessive shifting during
heavy traffic conditions. The second gear start is cancelled when:
•
•
The throttle pedal movement exceeds limits (quick step on the pedal)
The range selector is moved to P, N or R.
Curve Recognition: This feature is activated when the GS 20 detects a variation of front
wheel speeds via the CAN bus. The Mark 20 EI control module broadcasts the wheel
speed sensor signals and their speed variations for any control module programmed to
monitor this condition. When curves are recognized, the GS 20 inhibits up shifting until the
front wheel speed signals equalize indicating the vehicle is driving straight ahead. This feature enhances the vehicle handling characteristics when cornering at higher speeds.
Winter Drive Program: Wheel slip is calculated by the GS 20 based on wheel rotation
data provided by the traction control system via CAN bus. The GS 20 modifies shift characteristics to match winter mode for better traction. When active, the transmission will
start in second gear and the shift points are lowered. The purpose of this program is to
improve the drivability of the vehicle with slippery road conditions.
Cruise Control Program: When cruise control is activated, the MS 42.0 control module
communicates this status via the CAN bus. The GS 20 activates a program suitable for
active cruise control operation preventing pendulum locking/unlocking of the torque converter and minimizes up/down shifting. Additionally, the MS 42.0 can request a downshift if
the vehicle speed exceeds the set speed limit when coasting downhill.
Hill Recognition Program: The GS 20 activates this feature when it detects a high engine
load condition at lower road speeds. When the vehicle is traveling up hill the shift points
are raised to prevent repetitive up/down shifting.
23
Automatic Transmissions
NON AGS FUNCTIONS
The following features are part of the GS 20 automatic control system - but not AGS specific control features.
Manually Selected Extra Sport Program: Longer delay shift pattern with higher engine
RPM. This program is similar to the AGS detected sport program but requires the driver to
move the range selector from D to 4th gear or lower.
This program automatically returns to AGS shift program selection when the shifter is
returned to the D position.
Engine Warm Up Cycle: Based on the detected engine coolant temperature (CAN), the
shift points are raised during cold engine operation. This is implemented to speed up the
warm up cycle of the catalytic converter.
Downshift protection: If the driver moves the range selector to a lower gear at higher
vehicle speeds, the GS 20 delays the down shift until the road speed drops below a programmed value. This feature protects the powertrain from unnecessary loads ensuring long
life operation.
24
Automatic Transmissions
ADAPTIVE HYDRAULIC PRESSURE CONTROL:
The GS 20 monitors engine speed via the CAN bus along with the transmission input and
output speed signals simultaneously to determine the slip ratio and slip time during a shift.
Slip ratio and slip time are influenced by production related differences between transmissions and by aging.
The comparison of target & real slip allow the GS 20 to perform the adaptive pressure control function by modifying the PWM control of the main pressure regulator solenoid increasing the clutch apply pressures to compensate for internal slip. The adaptive pressure control function optimizes the shift quality and increases the life span of the clutch plates.
The adaptive pressure control feature is not an AGS function.
Clearing adaptation values with the DIS or
MoDiC only clears this pressure control
adaptation values. Clearing these values
can lead to bad shift quality until the shift
pressure is again optimized by the adaptation.
25
Automatic Transmisions
EMERGENCY PROGRAM (SAFETY MODE)
If a malfunction causes the GS 20 to activate the Emergency Program, the
transmission fault indicator and the Check Engine Light in the instrument cluster
both illuminate (CAN signal activation) and electronic control terminates.
The transmission shifts manually in the following sequence:
•
•
•
For range selector lever positions D, 4, 3 or 2, Fifth gear is immediately activated (no
electrical control). P, R and N positions operate normally.
Torque converter lock up clutch is not functional
Reverse lock out is also not functional.
If the vehicle is stopped and restarted with this condition, the vehicle drives normally until
the condition that initially caused the Emergency Program activation is once again detected.
If the initial problem was a power down of the GS 20 control module, the transmission will
shift manually in the following sequence:
•
•
•
For range selector lever position D, 4, 3 or 2, Fourth gear is immediately selected. P, R
and N positions operate normally.
Torque converter lock up clutch is not functional
Reverse lock out is also not functional.
26
Automatic Transmissions
SERVICE INFORMATION
TRANSMISSION FLUID:
•
Initial production transmissions are factory filled with DEXRON III.
•
Later production transmissions will be factory filled with Texaco ETL-7045 lifetime oil.
When the transition occurs, the fluid type will be noted by a label change on the transmission pan indicating the actual fluid type in the transmission.
Transmissions filled with Texaco 7045 Dexron III can be "topped off" with the Texaco ETL7045 oil if required after performing the oil level checking procedure with the DIS/MoDiC.
Fill Capacity:
Approximately 7 liters (not including torque converter)
Approximately 8 liters (including torque converter)
CHECKING TRANSMISSION FLUID LEVEL:
The Drain and Fill plugs are located as
shown:
Checking the transmission fluid level
requires the fluid temperature be
between 30OC and 50OC.
•
Connect the DIS or MoDiC to the 20 pin
diagnostic connector of the vehicle.
•
From the diagnosis start screen identify
the vehicle and press the continue arrow.
•
From the vehicle identification screen
press the continue arrow.
•
From the Fault Symptom Selection Menu press the "Function Selection" button on the
bottom left of the screen.
•
From the "Operations" column, select "Service Functions", then "Drive", then "Electronic
transmission control"
•
Then select "Oil Level Check" from the Components list on the right side of the screen
and press the "Test Schedule" button.
•
From the Test Schedule listing, select "Oil Level Check" and press the continue button.
•
Select 1. Oil Level Check by pressing the #1 button. Follow the instructions on screen
to carry out the oil level check procedure.
27
Automatic Transmissions
SERVICE AND REPLACEMENT PARTS
For a severely malfunctioning A5S 360R transmission, the service procedure is to exchange
it with a replacement core once an authorization has been obtained. However, there are
replacement parts available for Limited Service Repairs.
Transmission Identification:
As with all BMW transmissions, an identification plate is attached to the transmission housing. The plate provides a two character alpha code signifying identification.
Refer to the alpha code when ordering a replacement transmission. This code must be
checked against the parts system verifying the code is correct for the specific vehicle and
for possible code/part number supersession.
The ID plate of the A5S 360R provides the following data:
TWO CHARACTER
ALPHA CODE
BMW PART NUMBER
GM PART NUMBER
SERIAL NUMBER
TRANSMISSION CONTROL
CALIBRATION CODE
Alpha codes for the E46 as introduced are
“SW” for the 328i and “SX” for the 323i.
28
Automatic Transmissions
SW
Limited Service Repairs:
Minor electrical and mechanical repairs can be performed on the A5S 360R. The following
are included in the repair scope of the A5S 360R:
Service Parts: Oil Filter unit, Pan Gasket, Oil Filler and Drain plugs with seals.
Oil Leaks: Radial Seals and Gaskets
Mechanical Faults: Torque converter core replacement, Parking Pawl mechanism,
Hydraulic control faults - Valve Body Replacement
Electrical Faults - Shift Solenoids. Torque converter pressure regulator and Main Line oil
pressure regulator, Wiring harness (fluid temperature sensor), Range Selector Switch,
Turbine and output speed sensors.
29
Automatic Transmissions
DIAGNOSIS AND PROGRAMMING
The E46 diagnostic concept provides an minimization of Fault Symptom selections based
on areas of selection. Follow the test schedule provided by the DIS / MoDiC. The test
schedule is based on the selected fault symptom and stored fault codes.
FAULT CODES: The GS 20 monitors the A5S 360R and interfacing systems. When
faults are detected, the GS 20 stores the following fault codes
Fault Codes
BMW Code
30
Automatic Transmissions
Description
DTC
Hex code
61
None
3D
96
P1750
60
System Voltage Low
96
P1751
60
System Voltage High
Transmission Fluid Over Temperature
80
P1749
50
TCM Memory RAM/ROM/Programming fault
81
P1748
51
TCM NVM not Copied to RAM at Startup
60
P0705
3C
Position Switch Assembly
(Range Switch signal not plausible or faulted)
34
None
22
Fluid temperature Sensor Circuit Voltage Low/High
33
P0715
21
Transmission Input Speed Sensor Circuit
32
P0720
20
Transmission Output Speed Sensor circuit
150
P0727
96
CAN - Engine Speed Signal
50
P0731
32
Incorrect 1st Gear Ratio
52
P0732
34
Incorrect 2nd Gear Ratio
53
P0733
35
Incorrect 3rd Gear Ratio
54
P0734
36
Incorrect 4th Gear Ratio
55
P0735
37
Incorrect 5th Gear Ratio
48
P0740
30
Torque Converter Clutch System - Mechanical
0
None
1
Main Pressure Control solenoid circuit
129
P1747
81
CAN Time out DME / TCM
CAN Time out Instrument Cluster
131
None
83
130
None
82
CAN Time out ASC
144
P1747
90
CAN BUS ERROR Protocol
145
None
91
CAN Torque Reduction Signal
146
None
92
CAN Engine Torque Signal
19
None
13
Shift Lock Control Solenoid/Circuit
147
P1765
93
CAN Throttle Position Signal
148
None
94
CAN Engine Coolant Temperature Signal
CAN Wheel Speed
149
None
95
151
None
97
CAN Brake Switch
113
None
71
Kickdown switch circuit malfunction
83
P1746
53
Shift Lock Power Control Solenoid Circuit High
84
P1746
54
TCC/Shift Solenoid Power Control Circuit High
16
P0753
10
Shift Solenoid ‘A’ Control Circuit Low/High Voltage
17
P0758
11
Shift Solenoid ‘B’ Control Circuit Low/High Voltage
4
P0743
4
Torque Converter Clutch PWM Solenoid Control
Circuit
18
P0763
12
Shift Solenoid ‘C’ Control Circuit Low/High Voltage
GS 20 PROGRAMMING:
The control module must be programmed to update resident program data in an existing
or after replacing a defective GS 20 control module. As with previous systems, the fault
memory must be cleared and the system fully functional.
Connect a battery charger to the vehicle prior to programming to ensure adequate voltage
supply during the programming procedure. When programming is completed, clear the
system adaptation values using the DIS or MoDiC.
Always make sure the programming software is the latest version.
31
BASIC TROUBLESHOOTING
• Always personally verify the customer complaint.
•
Always verify that the complaint is truly a system malfunction.
• Perform a Quick Test to determine if the vehicle systems have logged fault codes.
•
Call up the faulted system or appropriate test schedule to verify the correct control
module is installed in the car.
•
Follow the Diagnostic Information System (DIS) on screen instructions and perform all
tests as specified.
•
Use the DIS and fault symptom diagnostic procedures as trained.
•
Follow the appropriate test module procedures for systems that malfunction but fail to
set faults in memory.
•
To get a thorough understanding of automatic transmission issues, a GM or ZF
Technical Specialist must be contacted whenever a vehicle is brought into the workshop
with an automatic transmission related concern. Always have the printouts of fault
codes stored in the DME and EGS and the transmission serial number available when
calling.
•
If there is no Service Information Bullitin published which addresses the specific
complaint, do not make any repairs to a 5 speed automatic transmission prior to
contacting a GM or ZF Technical Specialist. Contacts may be made by calling the
BMW Technical Hotline: 1-800 472-7222
32
Automatic Transmissions
A5S 325Z 5HP 19 ZF TRANSMISSION
Model: E46 All Versions
Production Dates: 323i/Ci/Cic : 3/00 to 8/00, 323it: from4/01,
330i/Ci/Cic: from 6/00, 325i/Ci/Cic: from 9/00
Objectives
After completing this module you should be able to:
•
Recognize the differences between the torque converters used in the 323i/325i and
the 330i.
•
Understand the purpose of overlap shifts.
•
Describe the method used to program the control unit.
•
Know how to check and fill the transmission fluid.
1. A5S325Z Automatic Transmission
1.1 Automatic
Transmission
A5S325Z
The A5S325Z automatic transmission was jointly designed
by BMW and ZF for BMW six-cylinder models with a power
output of up to 150 kW/204 bhp. It has electronic-hydraulic
control and operation, as is usual for BMW. In addition, it is
fitted with an adaptive transmission control system of the
kind used, for instance, in the A5S440Z.
The new automatic transmission offers:
-
Better shifts
Enhanced dynamics
Improved fuel economy
Quieter operation
KT-2352
Fig. 1: A5S325Z Automatic Transmission
34
Automatic Transmissions
3
5
7
6
8
9
11
12
13
10
14
1
4
2
3
15
22
21
2019
18 1716
KT-2507
Fig. 2: A5S325Z Transmission
1
Torque converter housing
12
Clutch G
2
Turbine
13
Clutch F
3
Impeller
14
Output flange
4
Torque converter clutch
15
Output speed sensor
5
Transmission case
16
Single planetary gear set
6
Clutch C
17
Oil filler plug in side of oil pan
7
Clutch B
18
Oil pan
8
Clutch E
19
Turbine speed sensor
9
Clutch A
20
Oil filter
10
Planetary gear set
21
Drain plug
11
Clutch D
22
Shift unit
35
4
Automatic Transmissions
Technical Data:
Transmission
type
automatic passenger-car transmission with five
gears as standard.
Torque capacity
max. torque
300 Nm at
3500 rpm
max. output
150 kW/204 bhp at
6000 rpm
Torque converter
Transmission
ratios
2.8 lt.
W254 with double CTC
2.5 lt.
W254 with single CTC
2.0 lt.
W254 with single CTC
first gear
3.67
second gear 2.00
third gear
1.41
fourth gear
1.00
fifth gear
reverse
4.10
0.74
Selector
positions
P-R-N-D and Steptronic
Control
electronic-hydraulic with adaptive control
Weight
On tow
transmission
61.7 kg
torque
converter
10.4 kg
oil
06.9 kg
total approx.
79.0 kg
200 km at 70 km/h
36
Automatic Transmissions
5
1.2
Converter
clutch
As in all automatic transmissions, power is transmitted via
the torque converter with converter clutch and via the drive
and brake clutches to the planetary gear and on to the
output flange.
The basic functions of the torque converter and the torque
converter clutch are described in the training manual "BMW
Automatic Transmission: Design and Function".
The features in which the torque converter and torque
converter clutch differ from the A5S310Z are as follows.
- The weight of the torque converter has been reduced and
the converter clutch has no torsion dampers, so the mass
moment of inertia has been optimised.
- No torsion damper in the torque converter clutch, further
optimising the mass moment of inertia.
- This transmission permits oil flow to continue when the
torque converter clutch closed. This reduces the oil
temperature in the torque converter.
The torque converter clutch linings have small ducts to
permit this flow of oil.
- The torque converter clutch is closed in third, fourth and
fifth gears. As in the A5S440Z, clutch closure is slipcontrolled.
Control is in the speed range from approximately
25 km/h to approximately 120 km/h, depending on the
load situation. The torque converter clutch is always
closed at speeds in excess of 120 km/h.
- The torque converter clutch for the 2.8 litre has two
linings (as in the A5S440Z). The version for 2.5 litre and
2.0 litre models has only one lining. This lining is on the
torque converter housing, not (as in the A5S310Z) on the
clutch.
KT-2506
KT-2510
Fig. 3: Torque converter clutch 2.5 litre (left) and 2.8 litre (right)
37
Automatic Transmissions6
1.3
Oil pump
The basic clutch functions are described in the training
manual "BMW Automatic Transmission: Design
and Function".
The delivery rate of the oil pump has been increased from
16 cm per revolution to 24 cm per revolution. This higher
delivery rate means that a controlled converter clutch can
be used.
The pump draws in oil via a filter and discharges the pressurized oil via a flow control valve which returns excess oil
not needed at high engine speeds to the pump intake side.
The flow control valve directs the pressurized oil via the
main pressure valve in the hydraulic shift unit. This valve
regulates the oil pressure and returns excess oil to the
intake duct, releasing energy to increase pressure on the
intake side in the same way as the flow control valve. This
increase in pressure prevents cavitation and reduces noise.
5
7
KT-2487
Fig. 4: Oil pump
1
Retaining ring
6
Needle bearing
2
Shaft seal
7
Impeller
3
Round seal
8
Centring pin
4
Pump housing
9
Corrugated washer
5
Pump ring gear
38
Automatic Transmissions
7
1.4
Clutches
The basic clutch functions are described in the training
manual "BMW Automatic Transmission: Design
and Function".
The ring-type multi-disc clutches A-B-E and F are drive
clutches which transmit engine power to the planetary gear
set. Clutches C-D and G are brake clutches which brace the
torque against the transmission case.
Shifts from first to second gear are assisted by a freewheel.
In these shifts, therefore, there is no clutch overlap.
Shifts from second to third, from third to fourth and from
fourth to fifth are overlap shifts. This means that one clutch
must continue to transmit drive at reduced main pressure
until the other clutch engages.
The transmission dispenses with brake bands, which has
led to improved shift quality.
39
Automatic Transmissions
8
3
2
1
5
4
7
6
KT-2493
Fig. 5: A5S325Z clutches
1
Clutch A
5
Clutch E
2
Clutch B
6
Clutch F
3
Clutch C
7
Clutch G
4
Clutch D with freewheel
Tolerance limits for the dished-spring forces were reduced
for all clutches, so fill-pressure tolerance is down. The gap
is now set by the snap ring so fill volume tolerances are
narrower. The increase in wear reserves boosts operational
dependability and transmission durability.
40
Automatic Transmissions
9
1.5
Transmission
diagram
D
CTC
C
G
F
B
A
E
KT-2381
Fig. 6: A5S325Z transmission diagram
Closed shift elements:
Gear
Clutch
A
B
Brake
C
1
●
2
●
●
3
●
●
4
●
❍
E
F
❍
●
G
1
●
●
●
●
●
5
R
D
Freewheel
●
●
●
●
●
= depending on operating status
41
10
Automatic Transmissions
1.6
Planetary
gear set
The basic functions of the planetary gear set are described
in the training manual "BMW Automatic Transmission:
Design and Function".
As in the A5S310Z, the A5S325Z transmission uses a
Ravigneau planetary gear set.
The bearings of the planetary gears have been improved in
this transmission (e.g. double bearings for short planet
gears and cage bearings for long planet gears). These
design modifications reduce gear noise and improve driving
characteristics.
Tail planetary gear set
The tail planetary gear set consists of a sun gear with its
four planet gears, a planet spider and a ring gear.
KT-2488
Fig. 7: Planetary gear set with tail planetary gear set
The planetary gear set consists of the following
components:
-
Ring gear
Small sun gear
Large sun gear
Planetary gears
The tail planetary gear set consists of the following
components.
-
Ring gear
Planetary gears
Spider
Sun gear
42
Automatic Transmissions
11
1.7
Oil pan
As in the A5S440Z, the A5S325Z has a flat gasket for the oil
pan. This modification maximizes the sealing properties.
In order to enhance accessibility for maintenance
personnel, the oil filler plug is in the side of the oil pan.
1.8
Transmission
weight
At approximately 79.0 kg, the A5S325Z is about 5 % lighter
than the A5S310Z. This increases fuel economy.
1.9
Position of
selector lever
and Steptronic function
The position of the selector lever and the Steptronic
function are the same as in the A5S310Z.
1.10 Modifications
to electronichydraulic
control
system
The basic functions of the electronic-hydraulic control
system are described in the training manual
"BMW Automatic Transmission: Design and Function".
Hydraulic shift unit
The A5S325Z has three solenoid valves and four electrical
pressure control valves to control the shift unit. Two of the
pressure control valves are for gear shifts. One controls the
modulation pressure and one operates the torque converter
clutch. Controlled converter clutch operation would not be
possible without a pressure control valve.
43
12
Automatic Transmissions
D
B
A
E
C
F
G
HV-G
HV-C
KV-G
D-EDS3
SV-2
KV-C
D-EDS2
1
RG-V
SV-3
ZS-V
ZV 5-4
SV-1
MOD-V
F1
SCHM.-V
DR-V2
MV 1
MV 2
D-EDS1
ZV 4-5
MV 3
2
HD-V
EDS-1
WD-V
SV-WD
EDS-2
WS
WK-V
DR-V1
EDS-3
F1
D
N
R
3
P
EDS-4
5
D-EDS4
6
4
7
1 23DNR P
KT-2619
Fig. 8: Hydraulic system
Key
1
Clutch valve with damper
2
Torque converter
3
Oil cooler
4
Lubrication
5
Electronic control unit
6
Pump
7
Position switch
Key to abbreviations
MV
Solenoid valve
EDS
Pressure switch
WS
Selector lever
D-EDS
Damper for pressure actuator
HV
Retaining valve
KV
Clutch valve
SV
Shift valve
ZS
Thrust/coasting valve
ZV
Thrust valve
MOD-V
Modulation valve
SCHM.-V
Lube-oil valve
RG-V
Valve for reverse lockout
DR-V
Pressure relief valve
HD-V
Main valve
WD-V
Torque converter pressure valve
WK-V
Torque converter clutch valve
Breather
Restrictor
Baffle
Branch
44
13
Automatic Transmissions
1.11 Solenoid
valve and
clutch logic
A5S325Z
SOLENOID VALVE LOGIC
POS/
GEAR
MV
CLUTCH LOGIC
EDS
Clutch
Freewheel
Brake
1
2
3
1
2
3
4
A
B
E
F
C
D
G
1g
R=
Reverse
★
-
-
★
-
★
-
-
★
-
-
-
★
★
-
N = Neutral
★
★
-
★
-
★
-
-
-
-
-
-
-
★
-
D, 1st gear
★
★
-
★
-
★
-
★
-
-
-
-
-
★
★
D, 2nd gear
★
★
-
★
★
★
-
★
-
-
-
★
-
★
-
D, 3rd gear
-
★
-
★
★
-
(★)
★
-
-
★
★
-
-
-
D, 4th gear
-
-
-
★
-
-
(★)
★
-
★
★
-
-
-
-
D, 5th gear
★
-
★-★
★
★
-
(★)
-
-
★
★
★
-
-
-
2, 1st gear
★
-
-
★
-
★
-
★
-
-
-
-
★
★
(★)
D, 5-4 drive
★
-
★
★
★
-
(★)
✪
-
★
★
✪
-
-
-
TC
-
-
-
-
-
-
★
-
-
-
-
-
-
-
-
45
14
Automatic Transmissions
1.12 Electronic
control unit
A new control unit is used for A5S325Z transmissions. This
control unit has also been fitted to A5S440Z transmissions
since model year '98. The new control unit has a modular
plug-in system with five chambers. Not all the plug modules
are used in the automatic transmission control unit. The
ground connections in module 1 are longer. This ensures
that these pins are the first to make contact when the plug
is pushed onto the control unit.
M1
M2
M3
M4
M5
KT-1468
Fig. 9: Plug
Key
M1
Module 1
M4
Module 4, automatic transmission
M2
Module 2
M5
Module 5
M3
Module 3, body
1
Pins used
2
Pins not used
These new high-end standard control units have shorter
access times on account of a new, more powerful 32-bit
processor with 256 k memory and a program run time of
approx. 10 ms. The old control units had an 8-bit processor
with 64 k memory and a run time of approx. 24 ms.
The new control units exclude the possibility of skip downshifts, for example from fifth to third. Downshifts can only be
sequential through the gears.
The control units optimise shift quality. The transmission
reacts faster to load changes when, for example, the driver
allows the car to coast and then immediately presses the
accelerator pedal to the floor. Under these conditions, the
A5S310Z transmission shifted up a gear and then shifted
back down. The A5S325Z transmission cancels the upshift,
so the transmission remains in the original gear. Shift
transition control, too, has been improved, and clutch
draining and filling are better matched. These measures
have considerably enhanced levels of shift comfort.
46
Automatic Transmissions
15
①
②
KT-2490
Fig. 10: Shift transition
Key
1
Gear signal
2
Turbine speed
3
Clutch opening under pressure
4
Clutch closing under pressure
5
Slip speed
6
Synchronization point
①
Controlled load transfer (CLT)
②
Controlled load shift (CLS)
47
16
Automatic Transmissions
1.13 Registering
turbine speed
A Hall sensor (1) registers turbine speed (spider speed) in
the A5S325Z transmission. The magnetic pole wheel (3) at
cylinder A (4) rotates at turbine speed and generates a pulse
frequency. This pulse frequency is registered by the Hall
sensor through the non-magnetic bowl (2).
This innovation enables speed to be measured much more
accurately than was the case with the A5S310Z transmission.
Synchronisation, in turn, can be calculated to a much finer
degree of precision. Shift quality benefits accordingly.
to EGS
Distance a
KT-2354
Fig. 11: Registering turbine speed
Key
1 Hall sensor
4
Cylinder A, rotating at
turbine speed
2 Non-magnetic bowl
5
Turbine speed
3 Magnetic ring with 18 pole pairs
uniformly spaced around the
circumference
6
Bowl speed
48
Automatic Transmissions
17
1.14 Programming
Flashcode programming is the same as that used for the
GS 8.55 control unit for the A5S440Z automatic transmission. The programming procedure is largely an adaptation of digital engine management programming with
features tailored to electronic transmission control. As in
digital engine management, flashcode control units can be
programmed 14 times.
Note:
The adaptation values always have to be
deleted once the electronic transmission
control unit has been programmed. The control
unit has to re-adapt after the adaptation values
have been deleted. The control unit adapts
automatically when the car is on the road.
It is, however, advisable to perform a test run
covering upshifts and downshifts through all
the gears.
The CAN bus is interrupted during programming, with the result that a CAN error
is stored in the control units connected
(ABS/ASC, DME etc.). Programming should
always be followed by diagnosis to clear
the fault memories of all the control units
connected to the CAN bus.
49
18
Automatic Transmissions
1.15 Modifications
to adaptive
transmission
control
How adaptive transmission control for A5S325Z transmissions differs from the implementation for A5S310Z
transmissions.
The basic function of adaptive transmission control is
described in the training manual "Adaptive transmission
control unit".
Adaptive transmission control is the same as that implemented for the A5S440Z transmission. This transmission,
therefore, has two adaptation modes for the A and S programs.
A program
Basic shift characteristic XE and shift characteristic E
are selected in the A program.
It is not possible to switch to the S or XS shift
characteristics.
S program
Basic shift characteristic S and performance-oriented
shift characteristic XS are selected in the S program.
It is not possible to switch to the XE or E shift
characteristics.
50
Automatic Transmissions
19
1.16 System
overview
with Steptronic for E46
KT-2351
Fig. 12: System overview with Steptronic for E46
Key
1
Ignition
11
Solenoid valves
2
DME master relay
12
Pressure regulator
3
Starter motor
13
Hall sensor
4
Electronic immobiliser
14
Inductive sensor
5
Shift lock
15
Temperature sensor
6
Selector lever and Steptronic
16
Selector lever switch
7
Auto down
17
Reversing light in E46
8
Manual gate
18
Instrument cluster
9
Auto up
19
ASC
10
Transmission control unit
20
DME
51
20
Automatic Transmissions
2
Service
Information
INFORMATION
5HP19 for M52B25 Specifications
Transmission Type
Transmission Torque Capacity
Torque Converter
Transmission Weight
Transmission Ratio
Transmission Oil
Filler plug torque
Drain plug torque
5 speed automatic, AGS 8.60.4 adaptive transmission control
Torque(max) at 3500 RPM = 300NM
254 mm dia. with slip controlled lock-up clutch
78.9 kg (with oil)
1st gear
3.67
2nd gear
2.00
3rd gear
1.41
4th gear
1.00
5th gear
0.74
Reverse
4.10
Lifetime Fill – Esso ATF LT 71141
BMW P/N 83 22 9 407 807
35NM
30NM
Fluid checking procedure is the same as A5S560Z, A5S440Z or A5S310Z. Refer to SIB 24 07 98.
The 5HP19 can be identified by the “ribbed” pan(1).
Drain plug location (2).
The 5HP19 identification tag (1) is located on the left
rear of the transmission.
The filler plug (2) is located on the left-rear side
(driver-side) of the transmission.
52
Automatic Transmissions
Transmission Application Chart
Trans.
Model
4HP 24 E9
A4S 310R
Vehicle
750iL (E32)
850i, Ci
525i (E34)
M50,
M50 TU
M50
M50 TU
M42
M52
M52/TU
M52
M44
M52/TU
M52TU
M54
M54
M54
M52TU
M54
M54
1997-99
1999-2000
9/00-3/01
200120019/99-9/00
9/00-3/00
2001-
A5S 360R
390R
A5S 310Z
530i, it, (E34)
M3
M3
323i (E46)
325i/330i (E46)
525i/530i (E39)
840Ci (E31),
540i (E39),
740i/iL (E38)
X5 4.4i
740i/iL (E32)
540i (E34)
840Ci
740i/iL (E38)
M60
S50 US
S52
M52TU
M54
M54
M62
M62/TU
M62/TU
M62TU
M60
1994-95
1995
1996-99
3/00-9/00
6/003/019/96-End prod.
19971/97-2001
20001993-94
1994-1995
1994-1995
1995-1996
A5S 325Z
A5S 440Z
A5S 560Z
750iL (E38)
M73/TU
1995-2001
840Ci (E31)
M62
1996-8/96
850Ci (E31)
M73
1995-End prod.
318i,is,ic (ti 95)
328i,(is,ic, -97)
Z3 2.3/2.8
323is,ic
318i,(is,ic, -97),ti,
Z3 1.9
528i (E39)
323i/328i (E46)
325it (E46)
325xi/it/330xi (E46)
Z3 2.5/3.0
528i (E39)
525i/530i (E39)
X5 3.0i (E53)
M70
Model Year
1988-94
1990-94
1990-92
1993-95
1992
1993-95
1992-95
1996-98
1997-2000
1998-99
1996-99
325i,is,ic
A4S 270R
Engine
M60
53
Automatic Transmissions
Review Questions
1. How does the vane pump of the A5S 360R transmission regulate fluid volume?
2. What type of signal is used to control the pressure regulator solenoid? What happens
to the fluid pressure if the control signal is switched off?
3. Describe how the transmission fluid heat exchanger operates.
4. How can the AGS/TCM module be distinguished from the DME/ECM?
5. Why does the AGS module monitor the brake pedal switch?
6. If no repairs are performed to the transmission, why is clearing the adaptation values not
recommended?
7. What steps must be performed before determining a transmission needs to be
replaced?
8. What is the difference between the torque converter lockup clutch between the two
engine displacements?
54
Automatic Transmissions
Table of Contents
E46 TRACTION AND STABILITY CONTROL
SYSTEMS
Subject
Page
MK20 EI ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Corner Braking Control (CBC). . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Electronic Brake Proportioning (EBV). . . . . . . . . . . . . . . . . . . . . . 6
Diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
DSC III MK20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
System Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
DSC Control Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Components
Control Module/Hydraulic Unit. . . . . . . . . . . . . . . . . . . . . . 11
Wheel Speed Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . .12
Brake Light Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Brake Fluid Level Switch. . . . . . . . . . . . . . . . . . . . . . . . . . 13
DSC Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Steering Angle Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . .14
CAN Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
Rotation Rate Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lateral Acceleration Sensor. . . . . . . . . . . . . . . . . . . . . . . . 17
I.P.O.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Hydraulic System Components
Charge Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
Master Cylinder/Fluid Resevoir. . . . . . . . . . . . . . . . . . . . . .20
Pressure Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
DSC Hydraulic Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
Diagnosis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
TEVES DSC III MK60. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
System Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Control unit/Hydraulic unit . . . . . . . . . . . . . . . . . . . . . . . . 27
CAN Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Tandem Master Brake Cylinder. . . . . . . . . . . . . . . . . . . . . 30
Subject
Page
Expansion Tank and Brake Fluid Level Switch. . . . . . . . . . .30
Brake Pressure Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . 31
Wheel Speed Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Rotation Rate Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Steering Angle Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Transverse Acceleration Sensor. . . . . . . . . . . . . . . . . . . . . 37
DSC Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Instrument Cluster Warning Indicators. . . . . . . . . . . . . . . . 39
Principle of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
ABS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
DSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Bosch DSC III 5.7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
System Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Control unit/Hydraulic unit . . . . . . . . . . . . . . . . . . . . . . . . 61
CAN Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
Tandem Master Brake Cylinder. . . . . . . . . . . . . . . . . . . . . 63
Expansion Tank and Brake Fluid Level Switch. . . . . . . . . . .63
Pre-charge Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Brake Pressure Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Brake Light Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Wheel Speed Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Integrated Rotation and Transverse Acceleration Sensor. . . 67
Steering Angle Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
DSC Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Instrument Cluster Warning Indicators. . . . . . . . . . . . . . . . 69
Principle of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
ABS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
DSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Traction and Stability Control Systems Application Chart. . . . . . . . 85
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
MK20 EI ASC
Model: E46/4
Production Dates: 6/98 to 6/99
Objectives
After completing this module you should be able to:
•
Identify the communication link between ASC and DME.
•
Understand the CBC function of ASC.
•
Understand the EBV function of ASC.
MK20 EI ASC
ASC was standard equipment on both the 1999 323i and 328i Models. The Teves Mark 20 EI system is used for the E46. The theory/operation of the slip control system is
unchanged from the previous ASC system. The major changes of the Mark 20 El are:
• The electronic control module is integrated into
the hydraulic unit.
• The throttle reduction operation is carried out
through the DME activation of the MDK motor.
• The ASC control module communicates with the AGS and DME control modules over
the CAN Bus.
4
E46 Traction and Stability Control Systems
The Mark 20 EI system includes the Cornering Brake Control (CBC) utilized in the Bosch
ASC 5 system. This feature reduces pressure build-up on the inside rear brake circuit
while cornering, if the threshold values for activation are exceeded.
5
E46 Traction and Stsbility Control Systems
ELECTRONIC BRAKE PROPORTIONING (EBV)
A new feature of the Mark 20 EI system is the Electronic distribution of the braking force
(EBV). This feature will adjust the braking force to the rear wheels based on the vehicle’s
loading to maximize the braking force at all wheels.
The control module monitors the wheel speed sensor inputs, when the brakes are applied,
to determine vehicle loading. The control module compares the rate at which the front and
rear axles are slowing down.
If the rear axle is slowing at a rate similar to the front it indicates that the vehicle is loaded
and more braking force can be applied to the rear calipers to stop the vehicle.
If the decel rate of the rear wheels is far less than the front, it indicates a lightly loaded vehicle. At this point, if the same braking force were applied to the front and rear axles, the vehicle would become unstable.
If this difference exceeds the threshold values programmed in the control module, EBV is
activated. The control module will cycle the inlet valves to the rear brakes to regulate the
braking force.
DIAGNOSIS
Diagnosis of the slip control system is carried out with the DIS or MoDiC using the fault
symptom driven troubleshooting procedures.
6
E46 Traction and Stability Control Systems
DSC III MK20
Model: E46 all versions except all-wheel drive
Production Dates: 6/99 to 9/00
Objectives
After completing this module you should be able to:
•
List the components used in the DSC III system.
•
Explain the intervention the DSC III can execute to control oversteer or understeer.
•
Describe the calibration required when replacing a steering angle sensor.
•
Explain the reason why a pre-charge pump is necessary.
INTRODUCTION
The DSC III system was introduced for the E46, beginning with Model Year 2000 production (E46/2: 6/99, E46/4: 9/99). The system is similar to the DSC III used on the E38 and
E39 vehicles, however it is manufactured by Teves for use in the E46.
The system incorporates all of the features of the previous Teves slip control system and
adds the lateral dynamic control of the DSC III system already installed on the E38/E39s.
The Teves DSC system is designed to maintain the lateral locating forces for the following:
• ABS braking control
• ASC +T traction control
• DSC - Dynamic Stability Control for oversteer and understeer conditions
SYSTEM OVERVIEW
The E46 DSC III system consists of the following components:
•
•
•
•
•
•
•
•
•
•
•
•
Control module/Hydraulic Unit (combined)
Four wheel speed sensors
Charge pump
Tandem Brake Master Cylinder
Steering Angle Sensor
Yaw Rate Sensor
Lateral Acceleration Sensor
Two Brake Pressure Sensors
Brake Fluid Level Switch
DSC Button
DSC Warning Indicator
CAN Interface (DME/AGS)
8
E46 Traction and Stability Control Systems
DSC CONTROL OVERVIEW
The Teves DSC system maintains the lateral location forces during all phases of operation
through;
• ABS - Hydraulic intervention preventing the wheels from locking during hard braking
• ASC +T - Engine drive torque reduction and/or hydraulic intervention on the drive
wheels to ensure straight line traction (acceleration - driving and deceleration)
• DSC - Engine drive torque reduction and/or hydraulic intervention on any wheel
brake during cornering to minimize oversteer and understeer conditions
DSC control can aid the driver in controlling the vehicle while driving but can not overcome
the laws of physics if the vehicle is being driven beyond the range of DSC control.
UNDERSTEER/OVERSTEER CONDITIONS
9
E46 Traction and Stability control systems
10
E46 Traction and Stability Control Systems
COMPONENTS
CONTROL MODULE/HYDRAULIC UNIT
The control module is installed in the engine compartment, on the right side, in the battery
well.
Both the control module and the hydraulic unit are replaceable as separate components.
All processing functions for ABS/ASC or DSC regulating functions are carried out in the one
control module. The module is linked to the CAN bus for communication with the DME and
AGS control modules. Additionally the CAN bus is used for communication with the steering angle sensor and for illumination of the ABS and DSC indicator lamps in the instrument
cluster.
The hydraulic unit consists of the following:
•
•
•
•
Four inlet solenoids
Four outlet solenoids
Two changeover solenoids
Two charge solenoids
11
E46 Traction and Stability control systems
WHEEL SPEED SENSORS
The E46 DSC III system uses the same inductive wheel speed sensors from the ASC
system.
BRAKE LIGHT SWITCH
The brake light input signal is used by the control module to interrupt an ASC regulation
control if the driver steps on the brakes during its operation.
This interruption does not take place during DSC regulation.
12
E46 Traction and Stability Control Systems
BRAKE FLUID LEVEL SWITCH
Fluid level switch is incorporated into the brake master cylinder reservoir. If the fluid level is
correct, the switch provides a ground signal to the DCS control module.
If the fluid level drops below the specified level, the switch opens and the ASC/DSC functions are switched off.
DSC BUTTON
The DSC system comes on every time the vehicle is switched on. The DSC button can be
used to switch the system off. The warning indicator lamp comes on when the system is
manually switched off
13
E46 Traction and Stability control systems
STEERING ANGLE SENSOR
The steering angle sensor is mounted at the bottom of the steering column, in front of the
flexible coupling. It utilizes two potentiometers to determine steering angle and the rate of
steering change. These signals are processed in the steering angle sensor and a digital output signal is passed over the CAN bus to the DSC control module.
The sensor requires calibration after repairs to the steering or suspension system. The sensor is calibrated using the DIS or MoDiC. Once calibrated, the sensor sends an ID number
to the DSC control module. The ID provides confirmation to the module that the angle sensor is properly calibrated.
Installing a new sensor or exchanging sensors with another vehicle will require that this calibration procedure is carried out.
14
E46 Traction and Stability Control Systems
CAN INTERFACE
The DSC control module communicates over the CAN line for the following:
•
•
•
•
Steering angle from the steering angle sensor
Engine control module for engine intervention
Transmission control module for shift intervention
Instrument cluster for illumination of the warning indicator lamps
15
E46 Traction and Stability control systems
ROTATION RATE SENSOR
The rotational rate sensor is mounted under the driver's seat. It provides a signal to the DSC
control module that corresponds to the vehicle's rotational speed around its axis (yaw
speed).
The sensor receives its operating power (5 volts) from the DSC control module and provides an output voltage of approx. 0.25 to 4.65 volts depending on the amount of yaw
exerted on the vehicle.
The sensor operates on the Coriolis effect to produce the output voltage. The element of
the sensor is a micromechanical double quartz tuning fork. A frequency of 11 Hertz is
applied to one side of the fork and as the vehicle turns on its axis, vibrations are induced
into the tips at the other end.
The sensor processes the signals produced by the fork and produces an analog voltage
signal that is proportional to the amount of yaw.
Based on the control module's programming parameters, the DSC will activate a DSC regulation cycle to ensure that the vehicle remains stable under all driving conditions.
16
E46 Traction and Stability Control Systems
LATERAL ACCELERATION SENSOR
The lateral acceleration sensor is mounted in the left "A" pillar. The sensor provides the DSC
control module with an input signal that corresponds to the degree of lateral acceleration
("G" forces) acting on the vehicle.
The sensor is a capacitive type with two capacitive plates (one fixed and one moving).
Under the effect of lateral acceleration, the one plate moves in relation to the fixed plate.
This results in a voltage signal being produced in proportion to the degree of lateral acceleration.
The voltage signal output of the sensor to the DSC control module ranges from 0.5 to 4.5
volts. When the vehicle is stationary, The standing voltage from the sensor is approximately 1.8 volts.
This signal is used in conjunction with the yaw sensor input to determine the degree of DSC
regulation required to maintain the vehicle's stability.
17
E46 Traction and Stability control systems
18
E46 Traction and Stability Control Systems
HYDRAULIC SYSTEM COMPONENTS
PRE-CHARGE PUMP
The pre-charge pump is installed between the master cylinder and the brake fluid reservoir.
During DSC controlled regulations that involve brake intervention, the pump ensures that
the required volume of fluid is available for the hydraulic unit.
When activated, the pre-charge pump draws fluid from the reservoir and delivers it to the
master cylinder at a pressure of 10 Bar.
19
E46 Traction and Stability control systems
MASTER CYLINDER/FLUID RESERVOIR
The master cylinder contains the central valves in both the front and rear brake circuits,
Similar to the Bosch DSC system. The central valves allow fluid to transfer during DSC controlled interventions.
The brake fluid reservoir has internal baffles that minimize fluid foaming during controlled
interventions. The charge pump pick up is mounted low on the reservoir to prevent air from
entering the system during regulation. The fluid level switch will signal the control module to
cancel DSC regulation if the fluid is below the safety margin level.
PRESSURE SENSORS
Two pressure sensors are installed on the master cylinder in the outlet ports for the front
and rear brake circuits. The sensors provide the DSC control module with an analog voltage signal in proportion to the brake pressure in the master cylinder.
20
E46 Traction and Stability Control Systems
DSC HYDRAULIC OPERATION
Based on the programming of the DSC control module, hydraulic intervention can be activated at any wheel brake as follows:
• ABS regulation for any wheel that is in danger of locking - causing the wheel to
skid.
• ASC regulation for either or both rear wheels to ensure that the optimum traction
is applied to the drive wheels
• DSC regulation for any wheel to correct for dynamic forces that are causing the
vehicle to become unstable. The DSC intervention only takes place on one wheel
of a corresponding axle.
Depending on the hydraulic intervention required, the charge pump, return pump, change
over valves, charging valves, inlet and outlet solenoids are activated to provide:
• Pressure build up for brake application
• Pressure hold to slow or stop the wheel
• Pressure release to allow the wheel to turn
21
E46 Traction and Stability control systems
DIAGNOSIS
Troubleshooting the E46 TEVES DSC system is carried out using the DIS or MoDiC.
The fault indicators in the instrument panel will illuminate when there is a fault and the system is off line.
Follow the diagnostic procedures as outlined with the tester to troubleshoot the E46 Teves
DSC system.
22
E46 Traction and Stability Control Systems
TEVES DSC III MK60
Model: E46 (except M3 and Xi) and E36/7
Production Date: From 9/00
Objectives
After completing this module you should be able to:
•
Identify the changes of the MK60 over the previous MK20EI system.
•
Understand the operation of the new wheel sensors.
•
Review the operating principles of ABS, ASC and DSC.
•
Describe the new ADB and DBC functions.
23
E46 Traction and Stability Control Systems
Purpose of the system
DSC III MK60 is supplied by Continental Teves and supersedes the Teves DSC III MK20 EI
system. The MK60 includes all of the features of the previous MK20 EI system and incorporates two additional functions:
•
DBC function
•
Modified ADB function
The most important changes from the MK20 EI are:
•
Reduction in size of the control unit/hydraulic Unit.
•
Installation of the hydraulic unit close to the master cylinder.
•
Elimination of a pre-charge pump.
•
Magneto resistive wheel speed sensors.
The Teves MK60 system is designed to maintain the vehicles stability during:
•
ABS braking regulation
•
ASC+T traction control
•
DSC for oversteer and understeer control
Additional features are also programmed into the control module to enhance driver safety
and comfort. These features are:
•
CBC Corner Brake Control
•
EBV
•
MSR
•
ADB
•
DBS Dynamic Brake System
Electronic Brake Proportioning
Engine Drag Torque Regulation
Automatic Differential Brake
24
E46 Traction and Stability Control Systems
ABS LAMP
KL 30
KL 15
ABS
DME
MAIN
RELAY
POWER SUPPLY
KL 15
POWER SUPPLY
DSC SWITCH
DSC
PUMP
LF
INLET (4X)
WHEEL
OUTLET (4X)
RF
MK60
HYDRAULIC
UNIT
CHANGEOVER (2x)
INTAKE (2x)
SPEED
LR
SENSORS
DSC III
MK 60
RR
BRAKE
PRESSURE
SIGNAL X2
BRAKE
PRESSURE
SENSORS
SIGNAL VOLTAGE
ROTATION
RATE SENSOR
POWER SUPPLY
ROTATION
RATE SENSOR
GROUND
47 PIN
REFERENCE
VOLTAGE
BRAKE
PRESSURE
SENSORS
POWER
GROUND
LATERAL
ACCELERATION SENSOR
STEERING
ANGLE SENSOR
CAN
1 2
80
3
4
1 2
5
3
4
5
60
SIGNAL VOLTAGE
40
12
DME
AGS
LATERAL
ACCELERATION SENSOR
UNLEADED GASOLINE ONLY
80
3
100
120 140
100
160
180
60
2
120
220
240
20
4
5
1/min
x1000
6
1
200
40
20
140
0
km/h
MPH
5030 20 15
12
7
!
BRAKE
BRAKE
ABS
ABS
miles
SERVICE
ENGINE
SOON
+
RIGHT REAR
EML
MK III
!
LEFT REAR
BRAKE
X
PROCESSED WHEEL SPEED
TO LSZ
DSC LAMP
GENERAL BRAKE
WARNING LAMP
WHEEL SPEED SENSOR REFERENCE VOLTAGE X 4
M
oD
SPLICE TO KOMBI
DIS
DIAGNOSIS
BMW DIS
BMW
BRAKE FLUID
LEVEL SWITCH
iC
PARK BRAKE
SWITCH
BMW DIS
BRAKE LIGHT
SWITCH
11
0
25
E46 Traction and Stability Control Systems
System Components
The Teves DSC III MK60 consists of the following components:
•
Integrated Control unit/Hydraulic unit with CAN Interface
•
Tandem Master Brake Cylinder
•
Brake Expansion Tank with Fluid Level Reed Contact in Cap
•
2 Brake Pressure Sensors
•
Brake Light Switch
•
4 Wheel Speed Sensors (active)
•
Rotation Rate Sensor (yaw)
•
Steering Angle Sensor (LEW)
•
Transverse Acceleration Sensor
•
DSC Button (part of SZM)
•
Instrument cluster Warning indicators
•
Hand brake Switch
•
Wiring Harness
26
E46 Traction and Stability Control Systems
Control Unit/Hydraulic Unit
The MK60 control unit/hydraulic unit is located
in the engine compartment on the left side
under the brake master cylinder.
Both the control unit and the hydraulic unit are
replaceable as separate components.
The pre-charge pump used on previous
systems is no longer required. Rapid pressure
build up is possible because of the close
proximity of the hydraulic unit to the master
cylinder and improvements in the design of the
return pump.
The control unit/hydraulic unit itself is 20%
smaller and lighter than the previous MK20 EI.
All processing functions for ABS, ASC or DSC are performed by the combined control
unit/hydraulic unit. The MK 60 control unit is also responsible for processing the wheel
speed signals and providing them to other control units.
The MK60 control unit for MY 2002 incorporates the RDW function into its scope of
control, making a separate RDW control unit unnecessary. The operating principle
continues to be based on the analysis of wheel speed.
27
E46 Traction and Stability Control Systems
MK60 Hydraulic Unit
REAR AXLE BRAKE CIRCUITS
FRONT AXLE BRAKE CIRCUITS
The hydraulic unit consists of an aluminum block containing 12 solenoid valves, 2 pressure
accumulators and the return pump.
•
4 inlet solenoid valves (N/O)
•
2 changeover solenoid valves (N/O)
•
4 outlet solenoid valves (N/C)
•
2 Intake solenoid valves (N/C)
The solenoid valving ensures that normal braking is possible in the event of a defective
control unit.
In ABS regulation the pump returns fluid back to the master cylinder circuits. In ASC/DSC
regulation with brake intervention, the pump is responsible for building up the brake
pressure required for the front and rear hydraulic circuits.
Note:
N/O= Normally Open
N/C= Normally Closed
28
E46 Traction and Stability Control Systems
CAN Interface
The MK60 is connected to the CAN bus for communication with the AGS, DME control
module, Steering Angle Sensor and the Instrument Cluster.
The CAN bus allows all of the connected control modules to send and receive information
and commands.
Communication with the MK60 includes:
•
DME - The DME sends current engine torque. MK60 commands the DME to reduce
(ASC/DSC) or raise (MSR) engine torque.
•
AGS - The MK60 commands the AGS to suppress shifts during regulation.
•
LEW - The MK60 receives steering angle information.
•
KOMBI - The MK60 commands the instrument cluster to activate or deactivate the
warning lamps.
•
All four wheels speed signals are sent over the CAN bus for use by other modules.
INSTRUMENT
CLUSTER
80
GS 20
60
MS 43.0
40
12
0
20
3
100
120 140
100
160
180
60
2
4
5
1/min
x1000
120
6
1
200
40
11
UNLEADED GASOLINE ONLY
80
220
20
240
140
0
km/h
5030 20 15
7
12
MPH
Mmiles
1 2
3
4
5
CAN BUS
SPLICE CONNECTIONS
FOR TWISTED PAIR CAN
LEW
MK 60
29
E46 Traction and Stability Control Systems
Tandem Master Brake Cylinder
The MK60 system uses a tandem master brake
cylinder fitted with central valves as in other DSC
master cylinders. The central valves allow fluid
to be drawn through the master cylinder during
ASC and DSC regulation. The hydraulic circuit is
divided front/rear.
An inlet for pre-charge pressure is no longer
used since the charge pump has been
eliminated from the MK60.
Both brake pressure sensors are mounted on
the master cylinder.
Expansion Tank and Brake Fluid Level Switch
The brake fluid expansion tank
has internal baffles that reduce
foaming during return pump
operation.
The expansion tank includes a
pick-up tube for clutch master
cylinder fluid supply.
The brake fluid level switch is
incorporated into the cap. The
switch is a reed contact switch.
If the brake fluid is at a sufficient
level, the switch is closed and
switched to ground.
If the fluid level drops below a specified level , the reed contacts open and the MK 60
responds by switching off the ASC/DSC functions.
Normal braking and ABS operation is unaffected.
30
E46 Traction and Stability Control Systems
Brake Pressure Sensors
Two brake pressure sensors are mounted on the master cylinder below the outlet ports for
the front and rear brake circuits. The sensors are provided a 5V reference voltage by the
MK 60 control unit.
The sensor provides the control unit with an analog signal proportional to brake pressure.
Voltage increases with increasing brake pressure.
Plausibility with BLS
The signal input from the brake
light switch is compared with the
pressure sensor values.
The pressure sensors must not
detect more that 5 bar when the
BLS is not actuated.
Both signals are used to form a
redundant BLS input which is
constantly monitored.
Note: Refer to the Workshop Hints for instructions on initializing the brake pressure sensors.
Brake Light Switch (BLS)
The brake switch is an input to the MK 60 to inform it that the brakes are being applied. If
the signal is received during an ASC regulation then brake regulation is interrupted.
31
E46 Traction and Stability Control Systems
Wheel Speed Sensors (active)
With the introduction of the Teves DSC III MK60, active wheel speed sensors that operate
on the principle of magnetoresistive effect are used for the first time on BMW vehicles.
The sensor element and evaluation module are two separate components within the
sensor housing.
1
6
5
4
8
3
7
10
2
1.
2.
3.
4.
5.
Metal pulse wheel
Magnet
Sensor element
Evaluation module
Support for sensor element
9
6.
7.
8.
9.
10.
Sensor wiring with weather boot
Ground contact ring
Fastening element
Sensor housing
Pick-up surface
Principle of operation of the magnetoresistive sensor
The active sensing of the magnetoresistive sensor is particularly suitable for advanced
stability control applications in which sensing at zero or near zero speed is required.
A permanent magnet in the sensor produces a magnetic field with the magnetic field stream
at a right angle to the sensing element.
The sensor element is a ferromagnetic alloy that changes its resistance based on the
influence of magnetic fields.
32
E46 Traction and Stability Control Systems
As the high portion of the pulse wheel approaches the sensing element, a deflection of the
magnetic field stream is created. This causes the resistance to change in the thin film
ferromagnetic layer of the sensor element.
1
4
5
3
2
1.
2.
3.
4.
5.
Metal pulse wheel
Magnet
Sensor element
Evaluation circuit
Magnetic field
The sensor element is affected by the direction of the magnetic field, not the field strength.
The field strength is not important as long as it is above a certain level. This allows the
sensor to tolerate variations in the field strength caused by age, temperature or
mechanical tolerances.
The resistance change in the sensor element affects the voltage that is supplied by the
evaluation circuit. The small amount of voltage provided to the sensor element is monitored
and the voltage changes (1 to 100mV) are converted into current pulses by the evaluation
module.
•
Signal High-14mA
•
Signal Low-7mA
The sensor evaluation circuit is supplied 12V by the MK60 control unit. Output voltage from
the sensor is approximately 10V. The control unit counts the high and low current pulses
to determine the wheel speed signal.
Front sensors are three wire because they have a separate ground wire.
Rear sensors are two wire and use the sensor case as a ground point.
33
E46 Traction and Stability Control Systems
Different sensors are used on the left and right side
front axle of the vehicle. The difference comes in the
length of the harness.
The connectors are blue to distinguish them apart
from the grey connectors used for sensors on the
MK20 EI.
The DSC III MK60 uses the same metal pulse
wheels used with the MK20 inductive sensors.
Front axle E46/Z3
Rear axle Z3
Rear axle E46, short
There are two types of sensors used in the rear axle of the E46:
•
The short sensor is used on the 325i (any transmission) and 330i automatic.
•
The long sensor is used on the 330i manual transmission version.
The Z3 uses the same sensors for the rear axle, left or right.
34
E46 Traction and Stability Control Systems
Rotation Rate Sensor
The Rotation Rate Sensor is mounted on a metal bracket under the drivers seat. The
sensor provides information to the MK60 concerning the vehicles speed around its main
axis (yaw).
The sensor has a three pin connector with the following connections:
•
•
•
5V reference
Signal
Ground
The sensor receives a reference voltage of 5V from the MK60 control unit and provides a
signal output of approximately 0.25 to 4.65V depending on the amount and direction of
yaw. If the sensor is defective a constant voltage will be sent to the MK60.
The sensor element is a micro-mechanical double quartz tuning fork. A frequency of 11
Hertz is applied to one side of the fork and as the vehicle turns on it’s axis, vibrations are
induced on the other end.
The sensor analyzes the signal produced by the fork and produces an analog voltage
signal that is proportional to the amount of yaw.
The rotation (yaw) rate is compared to the signal from the Steering Angle Sensor and the
Transverse Acceleration Sensor. If physical limits are beginning to be exceeded, the MK60
DSC will begin regulation by engine and brake intervention to attempt to stabilize the
vehicle. This is referred to as a GMR regulation.
Rotation Rate
Sensor
MK60 DSC III
The MK60 DSC III for M.Y. 2002 incorporates a combined Rotation rate and Transverse
Acceleration Sensor. The Sensor is connected to the MK60 control unit by the CAN bus.
The Z3 version will retain separate sensors until the E36/7 is replaced by the E46/6.
35
E46 Traction and Stability Control Systems
Steering Angle Sensor (LEW)
The Steering Angle Sensor is mounted towards the lower end of the steering column,
above the flexible coupling. The LEW consists of a potentiometer and a built in
microprocessor. The potentiometer has two pickups offset at 900 to one another. The raw
potentiometer signal is processed and converted into a digital signal that is transmitted over
the CAN bus to the MK60 DSC III control unit.
Po
te
nt
io
m
et
er
2
Po
te
nt
io
m
et
er
1
High signal
3600
2700
1800
900
00
90
0
1800
2700
3600
The sensor requires initialization in order to create a zero point default. Once initialized the
LEW sends an ID number to the DSC control unit. The ID provides confirmation that the
LEW is properly initialized.
The total steering wheel angle is determined by combining the CAN telegram signal, the
stored zero point default and the actual number of turns to the wheel. In order to prevent
the LEW from loosing count, KL 30 is provided to the sensor and it continues to record
even after the ignition has been switched off.
The MK60 DSC III calculates the drivers desired rate of turn from the steering angle signal.
POTENTIOMETER
HOUSING
Pin 1. KL 30
Pin 2. KL 87
6
PINBUS
CONNECTOR
CAN
CONNECTOR
(5 WIRES)
Pin 3. CAN high
Pin 4. CAN low
Pin 5. KL 31
CAN BUS MICROPROCESSOR
Pin 6. TXD
Note: Refer to the Workshop Hints for instructions on coding and initializing the sensor.
36
E46 Traction and Stability Control Systems
Transverse (Lateral) Acceleration Sensor
The Transverse Acceleration Sensor is
mounted in the left “A” pillar behind the driver’s
foot rest. The sensor provides the MK60 DSC
control unit with a signal that corresponds to
the degree of transverse acceleration (G forces)
acting on the vehicle.
The sensor is a capacitive sensor with two
plates. One plate is rigidly mounted, the other
plate is mounted on a spring. Under the effect
of transverse forces acting on the sensor the
distance between the plates changes.
This change of distance between the plates affects the capacitance of the sensor. The
evaluation circuitry converts the signal into an analog voltage that is transmitted to the
control unit.
The output signal of the sensor is between the range of 0.5 to 4.5 Volts. This corresponds
to -1.5 to 3.5g respectively. When the vehicle is stationary the output is 1.8V.
The transverse acceleration signal is used in the MK60 DSC III control unit along with the
rotation rate and steering angle signal to determine if DSC regulation is required to maintain
the vehicles stability.
Note: Refer to Workshop Hints for instructions on initializing sensor.
37
E46 Traction and Stability Control Systems
DSC Button
The DSC button is located on the SZM, however the SZM provides no processing, it is
simply a housing for the button which is hardwired to the MK60 control unit.
The DSC Button features two functions that can be set by varying the time the button is
held down for:
Button activation Function
Display
Short press
<2.5s
DSC light illuminated
Only the yaw control of the DSC is deactivated.
The ADB and DBC functions remain active.
A higher slip ratio is allowed up to 42 mph for the
purpose of improving traction in slippery
conditions. ASC uses different thresholds.
Long press
>2.5s
All ASC, ADB, DSC, GMR (yaw control) and DBC
control functions are deactivated.
DSC light and general
brake warning light
(yellow ABL) illuminated.
Used for service and use on dynamometers.
Pressing the button again returns the system to normal status. It is not possible to go
directly from one function to the next without first returning to normal status.
DSC
38
E46 Traction and Stability Control Systems
Instrument Cluster Warning Indicators
80
40
12
11
0
20
3
100
60
120 140
100
160
80
180
60
200
40
220
240
20
2
6
1
140
0
5030 20 15
7
12
!
Mmiles
SERVICE
ENGINE
SOON
5
120
km/h
MPH
4
1/min
x1000
BRAKE ABS
EML
Three warning indicator lamps are arranged in the instrument cluster:
•
DSC lamp: Indicates fault in DSC or system disabled by the switch.
•
ABS lamp: Indicates a fault in the ABS system.
•
ABL“BRAKE” lamp: This lamp is a general brake warning and illuminates two different
colors.
• Red indicates low brake fluid or hand brake engaged.
• Yellow indicates DSC/ABS fault or system disabled by the switch.
The DSC and yellow ABL lamp are controlled by the MK60 DSC III control unit via the CAN
bus. The ABS lamp is controlled directly by the MK60 via hardwire.
Hand brake Switch
The hand brake switch is an input to the MK60 DSC to cancel MSR regulation.
39
E46 Traction and Stability Control Systems
Principle of Operation
The scope of control for the MK60 DSC III is comprised of three systems:
•
•
•
ABS
ASC+T
DSC
Based on signals coming from the various sensors, the MK60 DSC III will determine which
system is best suited to maintain control of the vehicle.
In addition to the three basic systems, there are several sub-functions which are activated
during very specific circumstances. The sub-functions are:
•
CBC
•
EBV
CBC
EBV
ABS
ASC
ADB
MSR
• MSR
• ADB
• DBC
•
MBC
MBC
DSC
DBC
System: Anti-Lock Braking System (ABS)
The ABS system can prevent wheel lock when braking by comparing the four active wheel
speed sensors to the average vehicle speed. If a wheel is locking during braking or has
dropped below a speed threshold programmed in the control unit ABS braking will begin.
ABS braking is possible when vehicle speeds are above 12 kph (7mph).
ABS regulation has three phases:
•
•
•
Pressure Build
Pressure Hold
Pressure Release
40
E46 Traction and Stability Control Systems
Pressure Build already occurs during normal braking, so when ABS first intervenes it will
start holding pressure by energizing the Inlet Valve. For example, if the right rear wheel is
locking up, both Inlet Valves will be energized, regulating both wheels together. This logic
is known as Select Low. Front wheels can be regulated individually as needed to prevent
lockup.
Energizing the Inlet Valve closes the brake fluid passage to the calipers and traps the fluid
at the current pressure, thus not allowing the brake pressure to rise any further.
If the wheel speed does not increase the Pressure Release phase begins.
CUITS
FRONT AXLE BRAKE CIRCUITS
Pressure Release occurs when the control unit energizes the Outlet Valve while continuing
to hold the Inlet Valve closed. The trapped brake fluid is released out of the calipers,
reducing braking pressure.
At the same time, the pump is switched on which draws in the released brake fluid and
pumps it back into the pressure-build circuit restoring the volume of brake fluid again in
front of the Inlet valve.
Depending on conditions the ABS system may cycle between these three phases from 3
to 12 times a second to prevent wheel lock.
41
Teves DSC III MK 60
ABS Sub-functions
Corner Brake Control (CBC)
CBC can occur if the vehicle is cornering and ABS regulation is not taking place.
If the control unit detects transverse acceleration in excess of 0.6g and the brakes are
applied, CBC prevents a build up in brake pressure to the inside rear wheel. This prevents
the vehicle from entering into an unstable situation that can lead to Oversteer.
The MK60 accomplishes this by closing the Inlet Valve, thus not allowing brake pressure to
increase at the brake caliper.
The difference in braking force between the two rear wheels creates a yaw force that
opposes the oversteer and allows the vehicle to handle neutrally.
Weight of the
vehicle
Brake pressure
allowed to increase
42
E46 Traction and Stability Control Systems
Brake Pressure
Held
Electronic Brake Force Distribution (EBV)
EBV will adjust brake pressure to the rear axle based on the rate of slow-down of the rear
wheels, ensuring even brake force between the front and the rear of the vehicle.
The control unit monitors the wheel speed when the brakes are applied and compares the
deceleration of the front and rear axle to determine required regulation.
If the vehicle is moderately to fully loaded, the rear axle will take longer to slow down, rear
wheel brakes can then be applied at a higher pressure .
If a vehicle was lightly loaded, a similar brake pressure would be too great and result in an
unstable situation.
If EBV control intervention is required, the control unit cycles the inlet valve on the rear brake
calipers to prevent further build-up.
Benefits of EBV are:
•
•
•
Enhanced braking due to even distribution of brake force.
Rear wheel brake size can be increased.
Front and rear brakes wear at a similar rate.
43
E46 Traction and Stability Control Systems
Automatic Stability Control (ASC+T)
Based on input from the wheel speed sensors, the MK60 control unit determines if the
vehicle is loosing traction due to excessive longitudinal (straight line) wheel slip. An ASC
regulating sequence is initiated if the wheel slip exceeds the control units stored allowable
values.
A critical slip ratio of up to 5% between the wheels will cause the traction control regulation
to begin. This slip ratio is established when the system detects a wheel spin difference of
2MPH or greater.
ASC regulation is cancelled at any time if the brake pedal is applied.
44
E46 Traction and Stability Control Systems
The MK60 can control longitudinal wheel slip by two means:
•
•
Engine Intervention
Brake Intervention (ADB, drive wheels only)
Engine Intervention
Engine torque may be reduced by:
•
•
•
Reducing the throttle opening angle
Retarding the ignition
Canceling individual cylinders by fuel injection cutout.
The MK60 DSC III control unit determines the amount of torque reduction that is
necessary and sends the request for regulation to the DME via the CAN bus.
Brake Intervention (ADB)
Brake intervention is applied to the individual drive wheel which is loosing traction by
regulating the brake calipers in three phases:
•
•
•
Pressure Build
Pressure Hold
Pressure Release
When brake intervention is necessary, the front wheels must be isolated from the Pressure
Build sequence in the hydraulic unit.
Here is an example of an ASC brake intervention at the left rear wheel:
•
The Changeover Valve for the rear brake circuit, the right rear and both front Inlet Valves
are energized and closed.
• The rear brake circuit Intake Valve is energized and opened.
• The Return/Pressure pump is activated and draws brake fluid through the open Intake
Valve from the Master Cylinder (via the Central Valve) and delivers the pressurized fluid to
the open Inlet Valve braking the left rear wheel.
• Pressure Hold and Pressure Release are done by cycling the Inlet and Outlet Valves
similar to the ABS sequence described previously.
The control unit decides which regulation method should take place based on input
criteria and chooses from two regulating principles:
•
•
Select-High
Select-Low
45
E46 Traction and Stability Control Systems
Select-High Regulation
In a Select-High regulation, the MK60 control unit selects the drive wheel with the highest
amount of traction and uses it as the basis for evaluation.
•
•
Engine torque is reduced slightly by request to the DME.
The wheel with the least amount of traction is braked. This allows a torque transfer to
the wheel with the higher amount of traction (similar to a locking differential).
Select-High is used if the vehicle speed is below 40 kph (25 mph).
Select-Low Regulation
In a Select-Low regulation, the MK60 control unit selects the drive wheel with the lowest
amount of traction and uses it as the basis for evaluation.
•
•
Engine torque is reduced until the wheel slip is no longer present.
Brake regulation is not carried out.
Select-Low is used if the vehicle speed is above 40 kph (25 mph).
ASC Sub-functions
Engine Drag Torque Reduction (MSR)
If the vehicle is driven in low gear when coasting down hill, or if there is a sudden shift to a
lower gear, the wheels may be slowed by the engine’s braking effect too rapidly. This could
result in an unstable situation.
If the front wheels are turning faster than the rear wheels, the MK 60 control unit signals the
DME via the CAN bus to raise the engine torque. DME cancels fuel cut-off and allows the
engine speed to increase, this allows the drive wheels to accelerate to match the speed of
the non-driven wheels.
MSR regulation is cancelled if the brake pedal or hand brake are applied.
46
E46 Traction and Stability Control Systems
Modified ADB function (2-wheel drive vehicles equipped with MK60)
The ADB is an automatic differential lock that improves traction. The slipping wheel is
braked by pressure built up in the hydraulic unit. The drive torque can be transferred to the
wheel with the greater traction, which can transmit drive power to the road. This function
takes the place of a limited slip differential.
The MK60 DSC III system incorporates two methods of ADB based on the DSC switch
input to the control unit. With the system “on” the ADB works with engine intervention at
a threshold of below 40kph(24 mph).
Tapping the DSC switch (<2.5 s) increases the slip threshold of the ADB up to
approximately 70 kph (42 mph) for the purpose of increasing traction.
BMW
This feature is also helpful for example when rocking a vehicle out of mud or snow.
BRAKE
APPLIED
Low
High
Coefficient of friction
47
E46 Traction and Stability Control Systems
Dynamic Stability Control (DSC)
With the introduction of DSC systems, lateral dynamics were taken into account for the first
time. The MK60 DSC III system will initiate a DSC regulation sequence if the control unit
detects a difference between the drivers desired turning angle and the actual rotation angle
of the vehicle. The control unit determines vehicle stability based on:
•
•
•
•
Steering wheel angle
Wheel speed
Transverse acceleration forces
Rotation angle and speed (yaw)
Once the control unit determines that the vehicle is in an unstable situation, it also
identifies whether it is oversteering or understeering. This distinction is important because
it determines which control strategy should be used to help stabilize the vehicle.
DSC regulation consist of :
•
•
•
Engine intervention
Engine and brake intervention (any wheel)
Brake intervention
Oversteer Detected:
• Engine Torque Reduction.
• Brake applied to outside
wheels.
Understeer Detected:
• Engine Torque Reduction
• Brake applied to inside
rear wheel.
Comparison of
Steering Angle
and Wheel
Lateral
Acceleration
Value
Determination of
Drivers Desired
Turning Rate
Rotation (yaw)
Angle
Value
Determination of
Vehicle Actual
Turning Rate
Establish the Difference
Between Actual and Desired
Determination of Oversteer or Understeer
and Decide on Corrective Action
48
E46 Traction and Stability Control Systems
Understeer
Understeer occurs when the driver wishes to turn a corner but despite the front wheels
being turned in the direction of the curve the vehicle continues its track forward. This
occurs when the front wheels no longer have sufficient lateral locating force (traction).
The MK60 DSC III can identify the situation and initiate a corrective action based on engine
torque reduction followed by a controlled brake intervention sequence if needed.
Engine torque reduction is carried out by the DME from a request by the DSC via the CAN
bus. The DME telegrams the torque reduction confirmation back to the DSC.
Brake intervention is carried out by the MK60 hydraulic unit if the driver is not actively
braking. An example of a brake intervention at the inside rear wheel is as follows:
•
•
•
•
All Inlet Valves are closed except for the right rear inlet.
Intake Valve for rear circuit is opened.
Both Changeover Valves are closed.
Return pump operated.
UNDERSTEER CORRECTION
3. VEHICLE
COMES OUT
OF TURN
SUCCESFULLY
WITH DSC III
3
WITHOUT
DSC III
1. VEHICLE APPROACHES TURN:
- Driver steers into turn
- Brakes are applied
2. DSC III detects an Understeer
Condition based on vehicle speed,
wheel speed differential,
turning angle, lateral acceleration forces
and yaw angle.
- Engine torque reduction active
- Inside rear wheel brake regulate
1
2
- regulated brake slows
wheel down (and helps to
reduce vehicle speed). Wheel on
outside of curve speeds up due to power transfer thru differential.
Vehicle pivots in favor of curve. Combined, this forces the vehicle into the turn.
49
E46 Traction and Stability Control Systems
Just as an ASC regulation, DSC brake intervention carries out:
•
•
•
Pressure Build
Pressure Hold
Pressure release
REAR AXLE BRAKE CIRCUITS
50
E46 Traction and Stability Control Systems
FRONT AXLE BRAKE CIRCUITS
Oversteer
Oversteer occurs when the driver wishes to turn a corner and the tail of the vehicle slides
outward leading the turn. This is caused by the rear tires loosing traction and not being able
to hold against the centrifugal force acting upon the vehicle.
The MK60 DSC III can identify the situation and initiate a corrective action based on engine
torque reduction followed by a controlled brake intervention sequence if needed.
Engine torque reduction is carried out by the DME from a request by the DSC via the CAN
bus. The DME sends the torque reduction confirmation back to the DSC.
OVERSTEER CORRECTION
3. VEHICLE COMES
OUT OF TURN
SUCCESFULLY
1. VEHICLE APPROACES TURN AT HIGH RATE OF SPEED:
- Driver steers into turn and applies brakes to slow down.
WITH DSC III
WITHOUT
DSC III
1
3
2A. Lateral locating forces are
diminished on rear wheels
due to high speed and
centrifugal force of
vehicle in turn.
2
2D. The torque reduction and rear brake regulation
should stabilize the vehicle at this point. If not
the left front wheel has a high degree of lateral
locating force and is momentarily regulated.
This action deliberately causes the wheel to shed
a calculated degree of it's locating force. This
counteracts oversteer yaw at this wheel and also
aids in slowing the vehicle down to correct it.
2B. Driver tries to compensate by oversteering which
diminishes lateral locating force even further.
Simultaneously, rear of car starts to slide out.
2C. DSC III determines an OVERSTEER condition.
Engine torque is reduced via CAN Bus signalling.
Outside rear wheel is momentarily regulated to
counteract severe yaw angle (also helps to reduce
drive torque further.)
51
E46 Traction and Stability Control Systems
Brake intervention is carried out by the MK60 hydraulic unit if the driver is not actively
braking. An example of a brake intervention at the left outside wheel is as follows:
•
•
•
•
All Inlet Valves are closed except for the left rear inlet.
Intake Valve for rear circuit is opened.
Both Changeover Valves are closed.
Return pump operated.
REAR AXLE BRAKE CIRCUITS
52
E46 Traction and Stability Control Systems
FRONT AXLE BRAKE CIRCUITS
DSC Sub-functions
Dynamic Brake System (DBS)
DBS is designed to assist the driver in emergency braking situations by automatically
increasing pressure to the vehicles brake system. This allows the vehicle to stop in the
shortest distance possible. DBS was first available in 1999 Bosch DSC III 5.7 systems. It
is available on a Continental Teves system for the first time with MK60 DSC III.
The DBS system contains two functions: Dynamic Brake Control and Maximum Brake
Control. DBS functions are programmed into the MK60 control unit and require no additional hardware over conventional DSC.
Dynamic Brake Control (DBC)
The DBC function is designed to provide an increase in braking pressure up to the ABS
threshold during rapid (emergency) braking situations. The MK60 control unit monitors the
inputs from the brake light switch and the brake pressure sensors on the master cylinder.
The triggering criteria for activation of DBC is, how rapidly is the brake pressure increasing
with an application of the brake pedal. The triggering conditions are:
•
•
•
•
•
•
•
Brake light switch on.
Brake pressure in the master cylinder above threshold.
Brake pressure build-up speed above threshold.
Vehicle road speed above 3mph (5kmh).
Pressure sensor self test completed and sensors not faulted.
Vehicle traveling forward.
Not all of the wheels in ABS regulation range.
If the threshold for DBC triggering is achieved, the MK60 control unit will activate a
pressure build-up intervention by activating the return pump. The pressure at all wheels is
increased up to the ABS regulation point. This ensures that the maximum brake force is
applied to the vehicle.
During DBC the rear axle is controlled with Select-Low logic and the front wheels are
regulated individually. DBC will continue until:
•
•
•
The driver releases the brake pedal.
Brake pressure falls below threshold.
Vehicle road speed below 3mph.
DBC will also be switched off if a fault occurs in with any of the necessary input sensors.
A fault in DBC will illuminate the “BRAKE” (ABL) lamp yellow to warn the driver, depending
on the type of failure the DSC lamp may be illuminated as well.
53
E46 Traction and Stability Control Systems
Maximum Brake Control (MBC)
The MBC function is designed to support driver initiated braking by building up pressure in
the rear brake circuit when the front wheels are already in ABS regulation.
The additional braking pressure is applied to bring the rear wheels up to the ABS
regulation point shortening the stopping distance. The MBC function is triggered when the
brakes are applied more slowly than the threshold needed for a DBC regulation. The triggering conditions are:
•
•
•
•
•
Both front wheels in ABS regulation.
Vehicle road speed above 3mph (5kmh).
DBC and pressure sensor initialization test successful.
Vehicle traveling forward.
Rear wheels not in ABS regulation.
If the threshold for MBC triggering is achieved, the MK60 control unit will activate a
pressure build-up intervention by activating the return pump. The pressure at the rear
wheels is increased up to the ABS regulation point. This ensures that the maximum brake
force is applied to the vehicle.
The MBC function will be switched off if:
•
•
•
•
Front wheels drop out of ABS regulation.
The driver releases the brake pedal.
Brake pressure falls below threshold.
Vehicle road speed below 3mph.
MBC will also be switched off if a fault occurs in with any of the necessary input sensors.
A fault in MBC will illuminate the “BRAKE” (ABL) lamp yellow to warn the driver, depending
on the type of failure the DSC lamp may be illuminated as well.
54
E46 Traction and Stability Control Systems
Workshop Hints
Diagnosis
Diagnosis of the MK60 DSC III is carried out using the DISplus or MoDiC
Control Unit Functions:
Expert mode diagnosis available
at any time during troubleshooting. To enter: press the Control
Unit Functions button at the
right lower corner of the screen.
The contents are:
• Identification
• Delete Fault Memory
• Read Fault Memory
• Component Activation
• Status queries (requests)
Service Functions:
Provides access to specialized test modules
used as post repair procedures. To enter:
• Function Selection
• Service Functions
• Chassis
• Dynamic Stability Control MK60
The contents are:
• Connection Speed Sensor: A test to
verify the proper wiring to the wheel
speed sensors
• Connection Brake Lines: A test to
verify the proper brake pipe connections
to the hydraulic unit.
• Adjustment Functions: Test modules
to initialize certain components after
repair work is performed
• Steering Angle Sensor
• Lateral Acceleration Sensor
• Pressure Sensors
Test Modules: Faults with the MK60 system can be diagnosed using fault or symptom driven test
modules. To begin diagnosis:
• Perform the Quick Test.
• Select Vehicle Symptom from the Symptom Selection page.
• Select Test Module from Test Plan page.
• Press the Test Schedule Button.
Test Modules are configured in the E46 diagnosis concept.
55
E46 Traction and Stability Control Systems
Coding
Coding must be performed after replacement
of the MK60 control module or the steering
angle sensor. ZCS coding is found in the
Coding and Programming selection from the
start screen or when pressing the Change
button. Follow on-screen instructions for
initialization of components after completing
the coding process.
Print
Change
End
Services
BMW Coding/programming SELECTION
1
2
3
4
5
6
CAR MEMORY
KEY MEMORY
ZCS CODING
PROGRAMMING
ALIGNMENT EWS-DME
ALIGNMENT EWS-DDE
Note
Adjustment Functions
Adjustment (initialization) is required when:
• Replacing the MK60 Control Unit.
• Replacing/Re-coding the Steering Angle Sensor.
• Replacing one or both Brake Pressure Sensors.
• Replacing Lateral Acceleration Sensor.
Steering Angle Sensor
The steering angle sensor requires an offset adjustment after the sensor has been replaced,
coded or after repairs to the steering or suspension system. The offset adjustment informs
the steering angle sensor processor of the straight ahead position of the front wheels.
The adjustment is performed by completing the Test Module found in Service Functions.
Once the adjustment is complete the sensor sends an identification number over the CAN
bus to the DSC control unit. The ID provides confirmation that the steering angle sensor is
coded and has successfully completed the adjustment procedure.
Special Tools
Special Tools available for the Teves DSC III MK60 consist of:
47 Pin V-Cable 34 5 250
56
E46 Traction and Stability Control Systems
60 Pin Break-Out-Box
Subject
Page
Expansion Tank and Brake Fluid Level Switch. . . . . . . . . . .30
Brake Pressure Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . 31
Wheel Speed Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Rotation Rate Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Steering Angle Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
Transverse Acceleration Sensor. . . . . . . . . . . . . . . . . . . . . 37
DSC Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Instrument Cluster Warning Indicators. . . . . . . . . . . . . . . . 39
Principle of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
ABS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .44
DSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Bosch DSC III 5.7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
Purpose of the System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
I.P.O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .59
System Components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
Control unit/Hydraulic unit . . . . . . . . . . . . . . . . . . . . . . . . 61
CAN Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .62
Tandem Master Brake Cylinder. . . . . . . . . . . . . . . . . . . . . 63
Expansion Tank and Brake Fluid Level Switch. . . . . . . . . . .63
Pre-charge Pump. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Brake Pressure Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Brake Light Switch. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Wheel Speed Sensors. . . . . . . . . . . . . . . . . . . . . . . . . . . .65
Integrated Rotation and Transverse Acceleration Sensor. . . 67
Steering Angle Sensor. . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
DSC Button. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Instrument Cluster Warning Indicators. . . . . . . . . . . . . . . . 69
Principle of Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
ABS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
ASC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .74
DSC. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .77
Workshop Hints. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Traction and Stability Control Systems Application Chart. . . . . . . . 85
Review Questions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .86
BOSCH DSC III 5.7
Model: E46/16
Production Date: 330xi 6/00, 325xi 9/00
Objectives
After completing this module you should be able to:
•
Identify functions of the DSC 5.7 that are specific to All-Wheel Drive.
•
Identify the components used in the system.
•
Understand the operating principles of ABS, ASC and DSC.
57
E46 Traction and Stability Control Systems
Purpose of the System
The Bosch DSC III 5.7 is used in the E46/16 in place of the DSC III MK 60 used on 2wd
vehicles. The DSC system is the same as used in the E53. HDC is not a feature on 2001
Xi models.
Functions that are specific for the All-Wheel Drive system are:
•
Modified ABS function.
•
ASC+T (All-Wheel Drive version).
•
Four wheel ADB function.
The Bosch DSC III 5.7 system is designed to maintain the vehicle’s stability
during:
•
ABS braking regulation
•
ASC+T traction control
•
DSC for oversteer and understeer control
Additional features are also programmed into the control module to enhance driver safety
and comfort. These features are:
•
CBC Corner Brake Control
•
EBV
•
MSR Engine Drag Torque Reduction
•
DBS
Electronic Brake Proportioning
Dynamic Brake System
58
E46 Traction and Stability Control Systems
KL 30
KL 15
ABS LAMP
ABS
DME
MAIN
RELAY
KL 15
DSC
DSC SWITCH
POWER SUPPLY
POWER SUPPLY
LF
PUMP
WHEEL
INLET (4X)
RF
OUTLET (4X)
SPEED
LR
PRE-LOAD (2x)
SENSORS
DSC III
5.7
PRE-CHARGE
PUMP
CONTROL
ROTATION
RATE SENSOR
STEERING ANGLE
SENSOR
P
SIGNAL VOLTAGE
:00
HW
14
1 093
822
BM
80
4
1 2
5
3
4
ROTATION
RATE SENSOR
:00 37
HW W
CAN
3
SIGNAL VOLTAGE
078
60
1 2
Made in Germany
GROUND
SENSOR TEST
BOSCH
0000083
0 265 005 215
34 52 1 165 292
98300
219
078
BOSCH
0 265 005 215
34 52 1 165 292
98300
219
REFERENCE VOLTAGE
POWER SUPPLY
B
BRAKE
PRESSURE
SENSOR
42 Pin
Made in Germany
BRAKE PRESSURE
SIGNAL
0000083
RR
B
DSCIII 5.7
HYDRAULIC
UNIT
CHANGEOVER (2x)
5
40
12
11
0
AGS
DME
UNLEADED GASOLINE ONLY
20
80
200
40
220
240
20
3
100
120 140
100
160
180
60
2
120
5
6
0
km/h
MPH
4
1/min
x1000
1
140
5030 20 15
12
7
!
BRAKE ABS
BRAKE
ABS
ABS
miles
SERVICE
ENGINE
SOON
+
RIGHT REAR
MK III
X
TO LSZ
LEFT REAR
!
PARK BRAKE
SWITCH
GENERAL BRAKE
WARNING LAMP
SPLICE TO KOMBI
M
oD
DIAGNOSIS
iC
BMW DIS
DIS
BMW
BRAKE FLUID
LEVEL
BRAKE
DSC LAMP
PROCESSED WHEEL SPEED
BMW DIS
BRAKE LIGHT
SWITCH
EML
59
E46 Traction and Stability Control Systems
System Components
The Bosch DSC III 5.7 for the E46/16 consists of the following components:
•
Integrated Control Unit/Hydraulic Unit with CAN Interface
•
Tandem Brake Master Cylinder
•
Brake Fluid Expansion Tank with Integrated Level Sensor
•
Pre-Charge Pump
•
Brake Pressure Sensor (Located on Hydraulic Unit)
•
Brake Light Switch
•
4 Wheel Speed Sensors (Active)
•
Rotation Rate/Transverse Acceleration Integrated Sensor
•
Steering Angle Sensor
•
DSC Button
•
Instrument Cluster Warning Indicators
•
Handbrake Switch
•
Wiring Harness
60
E46 Traction and Stability Control Systems
Control Unit/Hydraulic Unit
The Bosch DSC III 5.7 control unit/hydraulic
unit is located inside the engine compartment
on the right hand side.
Both the control unit and the hydraulic unit
are replaceable as separate components.
All processing functions for ABS, ASC and
DSC are performed in the combined control/hydraulic unit. The control unit is also
responsible for processing the wheel speed
signals and providing them to other control
units.
LOW BRAKE
FLUID SIGNAL
Bosch DSC III 5.7
Hydraulic Unit
RESERVOIR
MASTER
CYLINDER
CHARGE
PUMP
CHARGE
PRESSURE
SIGNAL
P
DSC III 5.7
HYDRAULIC UNIT
REAR AXLE BRAKE CIRCUITS
PUMP
MOTOR
CHANGEOVER
VALVE
INTAKE
VALVE
P
P
PUMP
PUMP
LOW PRESSURE
ACCUMULATOR
OUTLET
VALVE
LEFT
REAR
BRAKE
CHANGEOVER
VALVE
INTAKE
VALVE
LOW PRESSURE
ACCUMULATOR
INLET
VALVE
FRONT AXLE BRAKE CIRCUITS
OUTLET
VALVE
INLET
VALVE
INLET
VALVE
RIGHT
REAR
BRAKE
OUTLET
VALVE
LEFT
FRONT
BRAKE
OUTLET
VALVE
INLET
VALVE
RIGHT
FRONT
BRAKE
The hydraulic unit consist of an aluminum block containing 12 solenoid valves, 2 pressure
accumulators and the return pump.
•
4 inlet solenoid valves (N/O)
•
2 changeover solenoid valves (N/O)
•
4 outlet solenoid valves (N/C)
•
2 intake solenoid valves (N/C)
The solenoid valving ensures that normal braking is possible in the event of a defective
control unit.
Note: N/O= Normally Open, N/C=Normally Closed
61
E46 Traction and Stability Control Systems
CAN Interface
The Bosch DSC III 5.7 is connected to the CAN bus for communication with the AGS, DME
control module, Steering Angle Sensor and the Instrument Cluster.
Using the CAN bus, all of the connected modules can receive information or send
commands.
Communication with the DSC III 5.7 includes:
•
DME - The DME sends current engine torque. DSC commands the DME to reduce
(ASC/DSC) or raise (MSR) engine torque.
•
AGS - The DSC commands the AGS to suppress shifts during regulation.
•
LEW - The DSC receives steering angle information.
•
KOMBI - The DSC commands the instrument cluster to activate or deactivate the
warning lamps.
•
All four wheels speed signals are sent over the CAN bus for use by other modules.
INSTRUMENT
CLUSTER
80
GS 20
60
MS 43.0
40
12
0
20
3
100
120 140
100
160
180
60
2
4
5
1/min
x1000
120
6
1
200
40
11
UNLEADED GASOLINE ONLY
80
220
20
240
140
0
km/h
5030 20 15
7
12
MPH
Mmiles
1 2
3
4
5
CAN BUS
SPLICE CONNECTIONS
FOR TWISTED PAIR CAN
LEW
H
SC
BO
DSC III 5.7
62
E46 Traction and Stability Control Systems
Tandem Brake Master Cylinder
The DSC III 5.7 system uses a tandem brake master cylinder fitted with central valves as
other DSC master cylinders. The central valves allow fluid to be drawn through the master
cylinder during ASC and DSC regulation. The hydraulic circuit is split front/rear.
An orifice for pre-charge pressure is fitted into the brake front axle circuit and is connected
to the pre-charge pump via a steel braided flexible line.
Brake Fluid Expansion Tank with Integrated Level Switch
The brake fluid expansion tank
has internal baffles that reduce
foaming during return pump
operation.
The expansion tank includes a
pick-up tube for clutch master
cylinder fluid supply and a
second lower one for the charge
pump supply.
The brake fluid level switch is
incorporated into the tank. The
switch is a reed contact switch. If
the brake fluid is at a sufficient
level, the switch is closed and
switched to ground.
If the fluid level drops below a specified level , the reed contacts open and the DSC
responds by switching off the ASC/DSC functions.
Normal braking and ABS operation is unaffected.
63
E46 Traction and Stability Control Systems
Pre-Charge Pump
The pre-charge pump is located below the master cylinder in the left side of the engine
compartment.
During ASC or DSC regulation with brake
intervention, the DSC control unit activates the
pre-charge pump. The pump delivers brake
fluid at a pressure of 10 to 15 Bar to the front
axle circuit of the master cylinder. The pressurized fluid also acts on the rear brake circuit of Pre-Charge
Pump
the master cylinder as well.
The Pre-charge pump ensures that an
adequate amount of brake fluid is available at
the hydraulic unit during brake regulation.
Brake Pressure Sensor
The brake pressure sensor is mounted on the
DSC hydraulic unit in the front axle circuit. The
sensor is provided with a 5V reference voltage
by the DSC control unit.
The sensor provides the control unit with an
analog signal proportional to brake pressure. Brake Pressure
Voltage increases with increasing brake
Sensor
pressure.
Plausibility with BLS
The signal input from the brake light switch is compared with the pressure sensor value.
The pressure sensor must not detect more that 5 bar when the BLS is not actuated.
Both signals are used to form a redundant BLS input which is monitored during all phases
64
E46 Traction and Stability Control Systems
Brake Light Switch (BLS)
The brake switch is an input to the DSC to inform it that the brakes are being applied. If
the signal is received during an ASC control, brake regulation is interrupted.
Wheel Speed Sensors (Active)
The E46/16 uses Hall-effect wheel speed sensors similar to other models with Bosch DSC
III 5.7. The advantages of the Hall sensors over the inductive sensors of the Teves MK 20EI
are:
•
•
•
Speed signal is available from 0.3km/h.
Signal strength is not dependent on road speed.
The signal supplied is a digital square wave.
The pulse wheel for the front axle circuit is integrated into the wheel bearing inner seal,
identical to that of E38, E39, E53, E52 models.
The pulse wheel for the rear axle circuit is identical to 2wd E46 models. The pulse wheel
is a plastic coated metal wheel attached to the rear stub axle outboard C.V. Both pulse
wheels produce 48 pulses:1 wheel revolution.
The color of the sensor connector is blue, just as the Magnetoresistive sensors of the Teves
MK 60 used on 2wd vehicles. The front sensors of the 2wd and 4wd versions of E46 are
physically different and will not fit in the wheel hub.
The rear sensors can be confused with the Teves MK 60 sensors and will fit in the rear axle
of the 4wd car however they are not compatible with the Bosch system.
65
E46 Traction and Stability Control Systems
8V
HALL ELEMENT
MAGNET
Principle of operation of the active wheel speed sensor
The sensor housing contains the evaluation circuitry, a Hall-effect transmitter and a permanent magnet. The wheel speed sensor receives a stabilized 8V operating power supply
from the control unit.
Both front and rear sensors are two-wire. One wire is for the power supply, the other provides a ground for the Hall element and also provides the input signal to the control module
If a tooth of the pulse wheel is opposite the sensor, the signal to the DSC III is high: approx.
1.9 to 3.9 V. When opposite of the gap, the signal to the DSC III is low at 0.35 to 1.3 V.
66
E46 Traction and Stability Control Systems
Integrated Rotation Rate and Transverse Acceleration Sensor
The E46/16 uses the combined rotation rate
/transverse acceleration sensor used in all
Bosch DSC III 5.7 systems. The sensor is
located under the drivers seat in front of the left
seat rail and is attached to a plate with a rubber
mounting to isolate it from vibrations.
For rotational speed, the sensor produces a
reference signal of 2.5 volts and a voltage input
signal from 0.7 to 4.3 volts. This signal
represents the rotational movement (yaw) of the
vehicle from the neutral straight ahead position.
The sensor also integrates the transverse acceleration signal (side-ways acceleration). The
signal range is 0.5V increasing to 4.5V as side forces (g-force) increase. This signal is
combined with the rotation signal to determine when to start DSC regulation.
12 V
BOSCH
B
0000083
0 265 005 215
34 52 1 165 292
98300
219
Made in Germany
078
yaw
2.5v
REFERENCE VOLTAGE
SIGNAL VOLTAGE
0.7v - 4.3v
-50
ACCELERATION SENSOR INPUT
O
+50
O
+
0.5 - 4.5 v
ROTATION
RATE SENSOR/
ACCELERATION SENSOR
Note: Adjustment of sensors is conducted separately in Service Functions of the Diagnosis
Program even though both sensors are contained in one housing.
67
Bosch DSC III 5.7 X
67
E46 Traction and Stability Control System
Steering Angle Sensor (LEW)
The Steering Angle Sensor is mounted towards the lower end of the steering column,
above the flexible coupling. The LEW consists of a potentiometer and a built in
microprocessor. The potentiometer has two pickups offset at 900 to one another. The raw
potentiometer signal is processed and converted into a digital signal that is transmitted over
the CAN bus to the DSC control unit.
Po
te
nt
io
Po
m
te
et
nt
io
er
2
m
et
er
1
High signal
3600
2700
1800
900
00
90
0
1800
2700
3600
The sensor requires initialization in-order to create a zero point default. Once initialized, the
LEW sends an ID number to the DSC control unit. The ID provides confirmation that the
LEW is properly initialized.
The total steering wheel angle is determined by combining the CAN telegram signal, the
stored zero point default and the actual number of turns to the wheel. In order to prevent
the LEW from loosing count, KL 30 is provided to the sensor and it continues to record
even after the ignition has been switched off.
The DSC calculates the drivers desired rate of turn from the steering angle signal.
POTENTIOMETER
HOUSING
Pin 1. KL 30
Pin 2. KL 87
Pin 3. CAN high
6CAN
PINBUS
CONNECTOR
CONNECTOR
(5 WIRES)
Pin 4. CAN low
Pin 5. KL 31
Pin 6. TXD
CAN BUS MICROPROCESSOR
Note: Refer to the Workshop Hints for instructions on coding and initializing the sensor.
68
E46 Traction and Stability Control Systems
DSC Button
The DSC button is located on the SZM however the SZM provides no processing, it is
simply a housing for the button which is a hardwired input to the DSC control unit.
The function of the button is different than for 2wd vehicles. Brake intervention
remains active for the ADB function after pressing the button to turn off the DSC.
Only ASC engine intervention and DSC yaw intervention are deactivated.
The DSC warning lamp will be illuminated to remind the driver that these functions have
been disabled. Pressing the button again returns the system to normal status.
Instrument Cluster Warning Indicators
80
40
12
11
0
20
3
100
60
120 140
100
160
80
180
60
200
40
220
240
20
2
1
140
6
0
5030 20 15
12
7
!
Mmiles
SERVICE
ENGI NE
SO ON
5
120
km/h
MPH
4
1/min
x1000
BRAKE ABS
EML
Three warning indicator lamps are arranged in the instrument cluster:
•
DSC lamp: Indicates fault in DSC or system disabled by the switch.
•
ABS lamp: Indicates a fault in the ABS system.
•
ABL“BRAKE” lamp: This lamp is a general brake warning and illuminates two different
colors.
• Red indicates low brake fluid or hand brake engaged.
• Yellow indicates DSC/ABS fault.
The DSC and yellow ABL lamps are controlled by the DSC control unit via the CAN bus.
The ABS lamp is controlled directly by the DSC III 5.7 control unit via hard wire.
69
E46 Traction and Stability Control Systems
Principle of Operation
The scope of control for the DSC III 5.7 is comprised of three systems:
•
•
•
ABS
ASC+T
DSC
Based on signals coming from the various sensors the DSC III will determine which system
is best suited to maintain control of the vehicle.
In addition to the three basic systems, there are several sub-functions which are activated
during very specific circumstances. The sub-functions are:
•
CBC
•
EBV
• MSR
CBC
ADB
ABS
ASC
MSR
EBV
• ADB
H
SC
BO
• DBC
•
MBC
MBC
DSC
DBC
System: Anti-Lock Braking System (ABS)
The ABS system can prevent wheel lock when braking by comparing the four active wheel
speed sensors to the average vehicle speed. If a wheel is locking during braking or has
dropped below a speed threshold programmed in the control unit ABS, braking will begin.
ABS braking is possible when vehicle speeds are above 12 km/h (7mph).
The function of ABS for All-Wheel Drive use has an additional variation. During braking on
loose surfaces the wedge effect is helpful. Gravel or dirt will build up in front of the tire when
the wheel is locked, creating an increased braking effect. The system allows the locking of
one or both front wheels up to approx. 20km/h (12mph). This “poor road surface logic”
does not affect steerability. As soon as the control unit detects steering wheel change, the
ABS system regulates normally again.
70
E46 Traction and Stability Control Systems
ABS regulation has three phases:
•
•
•
Pressure Build
Pressure Hold
Pressure Release
Pressure Build already occurs during normal braking, so when ABS first intervenes it will
start holding pressure by energizing the Inlet Valve. For example, if the right rear wheel is
locking up, both Inlet Valves will be energized, regulating both wheels together. This logic
is known as Select Low. Front wheels can be regulated individually as needed to prevent
lockup.
Energizing the Inlet Valve closes the brake fluid passage to the calipers and traps the fluid
at the current pressure, thus not allowing the brake pressure to rise any further.
If the wheel speed does not increase, the Pressure Release phase begins.
XLE BRAKE CIRCUITS
FRONT AXLE BRAKE CIRCUITS
Pressure Release occurs when the control unit energizes the Outlet Valve while continuing
to hold the Inlet Valve closed. The trapped brake fluid is released out of the calipers reducing braking pressure.
At the same time the pump is switched on which draws in the released brake fluid and
pumps it back into the pressure build-up circuit restoring the volume of brake fluid again in
front of the Inlet valve.
Depending on conditions the ABS system may cycle between these three phases from 3
to 12 times a second to prevent wheel lock.
71
E46 Traction and Stability Control Systems
ABS Sub-functions
Corner Brake Control (CBC)
CBC can occur if the vehicle is cornering and ABS regulation is not taking place.
If the control unit detects transverse acceleration in excess of 0.6g and the brakes are
applied, CBC prevents a build up in brake pressure to the inside rear wheel. This prevents
the vehicle from entering into an unstable situation that can lead to Oversteer.
The DSC III accomplishes this by closing the Inlet Valve, thus not allowing brake pressure
to increase at the brake caliper.
The difference in braking force between the two rear wheels creates a yaw force that
opposes the oversteer and allows the vehicle to handle neutrally.
Weight of the
vehicle
Brake pressure
allowed to increase
72
E46 Traction and Stability Control Systems
Brake Pressure
Held
Electronic Brake Force Distribution (EBV)
EBV will adjust brake pressure to the rear axle based on the rate of slow-down of the rear
wheels, ensuring even brake force between the front and the rear of the vehicle.
The control unit monitors the wheel speed when the brakes are applied and compares the
deceleration of the front and rear axle to determine required regulation.
If the vehicle is moderately to fully loaded the rear axle will take longer to slow down, rear
wheel brakes can then be applied at a higher pressure .
If a vehicle was lightly loaded, a similar brake pressure would be too great and result in an
unstable situation.
If EBV control intervention is required, the control unit cycles the inlet valve on the rear brake
calipers to prevent further build-up.
Benefits of EBV are:
•
•
•
Enhanced braking due to even distribution of brake force.
Rear wheel brake size can be increased.
Front and rear brakes wear at a similar rate.
73
E46 Traction and Stability Control Systems
Automatic Stability Control (ASC+T)
ASC prevents unintentional wheel slip of the drive wheels in every situation.
The DSC III control unit determines if the vehicle is loosing traction due to excessive longitudinal wheel slip based on input from the wheel speed sensors. An ASC regulating
sequence is initiated if the wheel slip exceeds the control units stored allowable values.
The DSC III can control longitudinal wheel slip by two means:
•
•
Automatic Stability Control ASC. Engine Intervention
Automatic Differential Brake ADB. Brake intervention
ASC Engine Intervention
Engine torque may be reduced by:
•
•
•
Reducing the throttle opening angle
Retarding the ignition
Canceling individual cylinders by fuel injection cutout.
The DSC III control unit determines the amount of torque reduction that is
necessary and sends the request for regulation to the DME via the CAN bus.
ADB Brake Intervention
The ADB is an automatic differential lock that improves traction. The slipping wheel is
braked by pressure built up in the hydraulic unit. The drive torque can be transferred to the
wheel with the greater traction, which can transmit drive power to the road. This function
acts much like a limited slip differential.
Brake intervention is applied to the individual wheel which is loosing traction by
regulating the brake calipers in three phases:
•
•
•
Pressure Build
Pressure Hold
Pressure Release
74
E46 Traction and Stability Control Systems
When brake intervention is necessary, the axle not being regulated must be isolated from
the Pressure Build sequence in the hydraulic unit. This is accomplished by closing both
Inlet Solenoid Valves for that axle.
Here is an example of an ADB brake intervention at the left rear wheel:
•
The Changeover Valve for the rear brake circuit, the right rear and both front Inlet Valves
are energized and closed.
• The rear brake circuit Intake Valve is energized and opened.
• The Return/Pressure pump is activated and draws brake fluid through the open Intake
Valve from the Master Cylinder (via the Central Valve) and delivers the pressurized fluid to
the open Inlet Valve braking the left rear wheel.
• Pressure Hold and Pressure Release are done by cycling the Inlet and Outlet Valves
similar to the ABS sequence described previously.
The drive torque can be distributed to the wheels with high friction coefficients (traction).
BMW
Transversal differential-lock function.
HIGH
BRAKE
APPLIED
LOW
BRAKE
APPLIED
LOW
HIGH
COEFFICIENT OF FRICTION
75
E46 Traction and Stability Control Systems
Longitudinal differential-lock function
BMW
By performing brake intervention at
the axle with a low friction coefficient, drive torque can be transmitted to the front wheels.
HIGH
HIGH
BRAKE
APPLIED
BRAKE
APPLIED
LOW
LOW
COEFFICIENT OF FRICTION
By performing brake intervention
at the diagonally opposing wheels
with a low friction coefficient, drive
torque can be transmitted to the
two wheels with more traction.
BMW
Longitudinal and transversal
differential-lock function
HIGH
HIGH
BRAKE
APPLIED
LOW
HIGH
COEFFICIENT OF FRICTION
76
E46 Traction and Stability Control Systems
ASC Sub-function
Engine Drag Torque Reduction (MSR)
If the vehicle is driven in low gear when coasting down hill, or if there is a sudden shift to a
lower gear, the wheels may be slowed down by the engine braking effect to rapidly. This
could result in an unstable situation.
If the front wheels are turning faster than the rear wheels the DSC III control unit signals the
DME via the CAN bus to raise the engine torque. DME cancels fuel cut-off and allows the
engine speed to increase, this allows the drive wheels to accelerate to match the speed of
the non-driven wheels.
MSR regulation is cancelled if the brake pedal or hand brake is applied.
Dynamic Stability Control (DSC)
With the introduction of DSC systems, lateral dynamics were taken into account for the first
time. The DSC III system will initiate a DSC regulation sequence if the control unit detects
a difference between the drivers desired turning angle and the actual rotation angle of the
vehicle. The control unit determines vehicle stability based on:
•
•
•
•
Steering wheel angle
Wheel speed
Transverse acceleration forces
Rotation angle and speed (yaw)
Once the control unit determines that the vehicle is in an unstable situation, it also
identifies whether it is oversteering or understeering. This distinction is important because
it determines which control strategy should be used to help stabalize the vehicle.
DSC regulation consist of :
•
•
•
Engine intervention
Engine and brake intervention (any wheel)
Brake intervention
77
E46 Traction and Stability Control Systems
Understeer
Understeer occurs when the driver wishes to turn a corner, but despite the front wheels
being turned in the direction of the curve, the vehicle continues its forward track. This
occurs when the front wheels no longer have sufficient lateral locating force (traction).
The DSC III can identify the situation and initiate a corrective action based on engine torque
reduction followed by a controlled brake intervention sequence if needed.
Engine torque reduction is carried out by the DME from a request by the DSC via the CAN
bus. The DME sends the torque reduction confirmation back to the DSC.
Brake intervention is carried out by the DSC III hydraulic unit if the driver is not actively
braking. An example of a brake intervention at the inside rear wheel is as follows:
•
•
•
•
All Inlet Valves are closed except for the right rear inlet.
Intake Valve for rear circuit is opened.
Both Changeover Valves are closed.
Return pump operated.
UNDERSTEER CORRECTION
3. VEHICLE
COMES OUT
OF TURN
SUCCESFULLY
WITH DSC III
3
WITHOUT
DSC III
1. VEHICLE APPROACHES TURN:
- Driver steers into turn
- Brakes are applied
2. DSC III detects an Understeer
Condition based on vehicle speed,
wheel speed differential,
turning angle, lateral acceleration forces
and yaw angle.
- Engine torque reduction active
- Inside rear wheel brake regulate
1
2
- regulated brake slows
wheel down (and helps to
reduce vehicle speed). Wheel on
outside of curve speeds up due to power transfer thru differential.
Vehicle pivots in favor of curve. Combined, this forces the vehicle into the turn.
78
E46 Traction and Stability Control Systems
Just as an ASC regulation, DSC brake intervention carries out:
•
•
•
Pressure Build
Pressure Hold
Pressure release
LOW BRAKE
FLUID SIGNAL
RESERVOIR
MASTER
CYLINDER
CHARGE
PUMP
CHARGE
PRESSURE
SIGNAL
P
DSC III 5.7
HYDRAULIC UNIT
REAR AXLE BRAKE CIRCUITS
PUMP
MOTOR
CHANGEOVER
VALVE
INTAKE
VALVE
P
LEFT
REAR
BRAKE
OUTLET
VALVE
CHANGEOVER
VALVE
INTAKE
VALVE
P
PUMP
LOW PRESSURE
ACCUMULATOR
INLET
VALVE
FRONT AXLE BRAKE CIRCUITS
PUMP
LOW PRESSURE
ACCUMULATOR
OUTLET
VALVE
RIGHT
REAR
BRAKE
INLET
VALVE
INLET
VALVE
OUTLET
VALVE
LEFT
FRONT
BRAKE
OUTLET
VALVE
INLET
VALVE
RIGHT
FRONT
BRAKE
79
E46 Traction and Stability Control Systems
Oversteer
Oversteer occurs when the driver wishes to turn a corner and the tail of the vehicle slides
outward, leading the turn. This is caused by the rear tires loosing traction and not being
able to hold against the centrifugal force acting upon the vehicle.
The DSC III can identify the situation and initiate a corrective action based on engine torque
reduction followed by a controlled brake intervention sequence if needed.
Engine torque reduction is carried out by the DME from a request by the DSC via the CAN
bus. The DME sends the torque reduction confirmation back to the DSC.
OVERSTEER CORRECTION
3. VEHICLE COMES
OUT OF TURN
SUCCESFULLY
1. VEHICLE APPROACES TURN AT HIGH RATE OF SPEED:
- Driver steers into turn and applies brakes to slow down.
WITH DSC III
WITHOUT
DSC III
1
3
2A. Lateral locating forces are
diminished on rear wheels
due to high speed and
centrifugal force of
vehicle in turn.
2
2D. The torque reduction and rear brake regulation
should stabilize the vehicle at this point. If not
the left front wheel has a high degree of lateral
locating force and is momentarily regulated.
This action deliberately causes the wheel to shed
a calculated degree of it's locating force. This
counteracts oversteer yaw at this wheel and also
aids in slowing the vehicle down to correct it.
80
E46 Traction and Stability Control Systems
2B. Driver tries to compensate by oversteering which
diminishes lateral locating force even further.
Simultaneously, rear of car starts to slide out.
2C. DSC III determines an OVERSTEER condition.
Engine torque is reduced via CAN Bus signalling.
Outside rear wheel is momentarily regulated to
counteract severe yaw angle (also helps to reduce
drive torque further.)
DSC Sub-functions
Dynamic Brake System (DBS)
DBS is designed to assist the driver in emergency braking situations by automatically
increasing pressure to the vehicles brake system. This allows the vehicle to stop in the
shortest distance possible. DBS was first available in 1999 Bosch DSC III 5.7 systems.
The DBS system contains two functions: Dynamic Brake Control and Maximum Brake
Control. DBS functions are programmed into the DSC III control unit and require no additional hardware over conventional DSC.
Dynamic Brake Control (DBC)
The DBC function is designed to provide an increase in braking pressure up to the ABS
threshold during rapid (emergency) braking situations. The DSC III control unit monitors the
inputs from the brake light switch and the brake pressure sensor. The triggering criteria for
activation of DBC is, how rapidly is the brake pressure increasing with an application of the
brake pedal. The triggering conditions are:
•
•
•
•
•
•
•
Brake light switch on.
Brake pressure in the master cylinder above threshold.
Brake pressure build-up speed above threshold.
Vehicle road speed above 3mph (5km/h).
Pressure sensor self test completed and sensor not faulted.
Vehicle traveling forward.
Not all of the wheels in ABS regulation range.
If the threshold for DBC triggering is achieved, the DSC III control unit will activate a
pressure build-up intervention by activating the pre-charge and return pump. The pressure
at all wheels is increased up to the ABS regulation point. This ensures that the maximum
brake force is applied to the vehicle.
During DBC the rear axle is controlled with Select-Low logic and the front wheels are
regulated individually. DBC will continue until:
•
•
•
The driver releases the brake pedal.
Brake pressure falls below threshold.
Vehicle road speed below 3mph.
DBC will also be switched off if a fault occurs in with any of the necessary input sensors.
A fault in DBC will illuminate the “BRAKE” (ABL) lamp yellow to warn the driver, depending
on the failure the DSC lamp may be illuminated as well.
81
E46 Traction and Stability Control Systems
Maximum Brake Control (MBC)
The MBC function is designed to support driver initiated braking by building up pressure in
the rear brake circuit when the front wheels are already in ABS regulation.
The additional braking pressure is designed to bring the rear wheels up to the ABS
regulation point shortening the stopping distance. The MBC function is triggered when the
brakes are applied more slowly than the threshold needed for a DBC regulation. The triggering conditions are:
•
•
•
•
•
Both front wheels in ABS regulation.
Vehicle road speed above 3mph (5km/h).
DBC and pressure sensor initialization test successful.
Vehicle traveling forward.
Rear wheels not in ABS regulation.
If the threshold for MBC triggering is achieved, the DSC III control unit will activate a
pressure build-up intervention by activating the return pump. The pressure at the rear
wheels is increased up to the ABS regulation point. This ensures that the maximum brake
force is applied to the vehicle.
The MBC function will be switched off if:
•
•
•
•
Front wheels drop out of ABS regulation.
The driver releases the brake pedal.
Brake pressure falls below threshold.
Vehicle road speed below 3mph.
MBC will also be switched off if a fault occurs in with any of the necessary input sensors.
A fault in MBC will illuminate the “BRAKE” (ABL) lamp yellow to warn the driver, depending
on the failure the DSC lamp may be illuminated as well.
82
E46 Traction and Stability Control Systems
Workshop Hints
Diagnosis of the DSC III 5.7 is carried out using the DISplus or MoDiC. The diagnosis
program utilizes the symptom driven diagnostics taken from the E53.
The all-wheel drive models of the E46 series do not have their own model identification and
all-wheel drive specific equipment (i.e. DSC III 5.7) is not detected automatically. All-wheel
drive identification is performed by manually selecting it from a pop-up dialog box when a
document or test module is called up which has a variation for all-wheel drive.
Diagnosis: Faults with the DSC III 5.7 system
can be diagnosed using symptom driven test
modules. To begin diagnosis:
• Perform the Quick Test.
• Page right.
• Press the Function Selection Button.
• Select Complete Vehicle.
• Select Chassis.
• Select “Yes” for All-Wheel.
• Select Dynamic Stability Control.
• Press the Test Schedule Button.
Service Functions: Provides access to
specialized functions used in post repair
procedures. To enter:
• Select Service Functions while in
Diagnosis Program.
•
Test Code: Used to print control unit
fault information needed for component
analysis.
Diagnosis can occur using Fault Symptoms or
Expert Mode troubleshooting.
•
Adjust Steering-Angle Sensor:
Used to adjust off-set for steering angle
sensor when repairs or adjustments to
steering have been made.
•
Adjust Transversal Acceleration
Sensor/Adjust Rotation Rate
Sensor: Used to adjust offset for each
sensor.
•
Bleeding,ABS/DSCHydraulics
/Precharging-pump circuit:
Used in purging air after repairs and for
brake fluid flushes.
•
ABS/DSC Final Test: Used to verify
the proper brake pipe connections to
the hydraulic unit and wheel speed
sensor connections.
Print
Change
The Contents are:
Services
End
BMW Diagnosis IDENTIFICATION
Anti-lock BrakeSystem with
Dynamic Stability Control
(ABS/DSC5.7, E53,E46/16)
Part number: 4 005 353
Hardware number: 5.1
Software number: 3.0
Diagnosis index: 14
Coding index: 13
Bus index:60
Production date:37/99
Supplier: Bosch
Note
Function
Selection
Documents
Test Schedule
TIS
Measuring
System
Control unit
Functions
83
E46 Traction and Stability Control Systems
Coding
Coding must be performed after replacement
of the DSC III control module or the steering
angle sensor. ZCS coding is found in the
Coding and Programming selection from the
start screen or when pressing the Change
button. Follow on-screen instructions for
initialization of components after completing
the coding process.
Print
Change
End
Services
BMW Coding/programming SELECTION
1
2
3
4
5
6
CAR MEMORY
KEY MEMORY
ZCS CODING
PROGRAMMING
ALIGNMENT EWS-DME
ALIGNMENT EWS-DDE
Note
Adjustment Functions
Adjustment (initialization) of certain components is required when:
• Replacing the DSC III Control Unit.
• Replacing/Re-coding the Steering Angle Sensor.
• Replacing Rotation/Lateral Acceleration Sensor.
Steering Angle Sensor
The steering angle sensor requires an offset adjustment after the sensor has been replaced,
coded or after repairs to the steering or suspension system. The offset adjustment informs
the steering angle sensor processor of the straight ahead position of the front wheels.
The adjustment is performed by completing the Test Module found in Service Functions.
Once the adjustment is complete, the sensor sends an identification number over the CAN
bus to the DSC control unit. The ID provides confirmation that the steering angle sensor is
coded and has successfully completed the adjustment procedure.
Special Tools
Special Tools available for the Bosch DSC III 5.7 consist of:
42 Pin V-Cable 34 5 240
84
Bosch DSC III 5.7 X
60 Pin Break-Out-Box
Traction and Stability Control Systems Application Chart
1998MY
1999MY
E36
Z3/Coupe
E46
E39
E38
E53
ASC+T
ASC+T
MK IV G
N/A
9/97
ASC+T5
S: 528i
9/97
DSC III 5.3
S: 740i/il
S: 750iL
N/A
N/A
3/98
DSC III 5.7
S: 740i/iL
S: 750iL
N/A
N/A
DSC III 5.7
S: 540i
O: 528i
6/99
DSC III 5.7
Standard all
models
3/99
DSC III 5.7
Standard all
models
9/99
DSC III
5.7
1/00
DSC III
5.7
DSC III 5.7
DSC III 5.7
DSC III DSC III
5.7
5.7
ASC+T
MK IV G
328iC/318ti
2000MY
N/A
2001MY
N/A
ASC MK20 EI
except M
versions
ASC MK20 EI
ASC +T MK IV
M/coupe/roadst
er
From 4/99
MK20 DSC III
6/99
MK20 DSC III
From 9/00
MK60 DSC III
From 9/00
MK60 DSC III
M-versions
MK 20 DSC III
M3
MK20 EI
DSC III 5.3
S: 540i
N/A 528i
9/98
ASC+T5
S: 528i
E52
E46/16 All
wheel drive
DSC III 5.7
S = STANDARD EQUIPMENT
O = OPTIONAL EQUIPMENT
85
E46 Traction and Stability Control Systems
Review Questions
1. How does the MK20 EI ASC system communicate with DME to reduce engine power
during an intervention?
2. Which component in the DSC III MK20 system is used to build-up pressure in the front
axle circuit during DSC intervention?
3. What type of sensors are used in the MK20 ASC and DSC systems?
4. What is the difference in ABS control logic for the E46/16 in comparison to the 2wd
models?
5. What service procedures are required when replacing a steering angle sensor?
5. What is the effect to the Bosch DSC III when the system is disabled by the DSC
button? What about the button operation in the Teves MK60?
6. Describe the operation of the “Automatic Differential Lock” function.
7. Why is a pre-charge pump not required in the MK60 system?
86
E46 Traction and Stability Control Systems
Review Questions
8. What is the purpose of the two sensors on the MK20 and MK60 DSC III master
cylinder and what is their relationship with the BLS (Brake light switch)?
9. What is the difference of the signal produced by the magneto-resistive and a Hall-effect
wheel sensor?
10. List the various sensors used to detect oversteer/understeer in the DSC III systems.
11. What is the purpose of the DBS sub-function?
87
E46 Traction and Stability Control Systems