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Transcript
OBJECTIVES
After studying Chapter 25, the reader should be able to:
1. Prepare for ASE Electrical/Electronic Systems (A6)
certification test content area “H” (Accessories
Diagnosis and Repair).
2. Explain how cruise control operates and how to
diagnose the circuit.
3. Describe how power door locks and windows
operate.
4. Describe how a keyless remote can be
reprogrammed.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
• Major components of a
typical cruise control
system include the
following:
– Servo unit.
– Computer or cruise
control module.
– Speed set control.
– Safety release
switches.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 25-1 This cruise control servo unit has
an electrical connection with wires that go to the
cruise control module or the vehicle computer,
depending on the vehicle. The vacuum hoses
supply engine manifold vacuum to the rubber
diaphragm that moves the throttle linkage to
maintain the preset speed.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
FIGURE 25-2 A cruise control used on a Toyota/Lexus.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Cruise Control Operation
• When the set button is depressed on the cruise
control, solenoid values on the servo unit allow
engine vacuum to be applied to one side of the
diaphragm, which is attached to the throttle plate of
the engine through a cable or linkage.
– One solenoid opens and closes to control the passage,
which allows engine vacuum to be applied to the
diaphragm of the servo unit, increasing the throttle
opening.
– One solenoid bleeds air back into the sensor chamber to
reduce the throttle opening.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Noncomputer-Controlled Resume-Type Cruise Control
• Most resume-style noncomputer-controlled cruise
control systems use a two-piece rubber clutch to
retain a “mechanical memory” of the vehicle road
speed.
• The speed is “remembered” by the position of the
split rubber clutch.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Computer-Controlled Cruise Control
• Most computer-controlled cruise control systems
use the vehicle’s speed sensor input to the enginecontrol computer for speed reference.
• Computer-controlled cruise control units also use
servo units for throttle control, control switches for
driver control of cruise control functions, and both
electrical and vacuum brake pedal release
switches.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Computer-Controlled Cruise Control
FIGURE 25-3 Circuit
diagram of a typical
electronic cruise control
system.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Electronic Throttle Cruise Control
• Many vehicles are
equipped with an
electronic throttle
control (ETC)
system.
• The PCM then
commands the
throttle to the
necessary position of FIGURE 25-4 A typical electronic throttle with
the protective covers removed.
the throttle plate.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Diagnosis and Service
• Any fault in the APP sensor or ETC system will
disable the cruise control function.
• Always follow the specified troubleshooting
procedures, which will usually include the use of a
scan tool to properly diagnose the ETC system.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
USE TRAILER TOW MODE
• When this mode is
selected, the
automatic
transmission
downshifts almost
as soon as the
vehicle speed starts
to decrease.
FIGURE 25-5 A trailer icon lights on the dash of
this Cadillac when the transmission trailer towing
mode is selected.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Troubleshooting Cruise Control
• The usual steps in the diagnosis of an inoperative
or incorrectly operating cruise control include the
following:
Step 1 Check that the cruise control fuse is not blown and
that the cruise control dash light is on when the cruise
control is turned on.
Step 2 Check for proper operation of the brake and/or
clutch switch.
Step 3 Inspect the throttle cable and linkage between the
sensor unit and the throttle plate for proper operation
without binding or sticking.
Step 4 Check the vacuum hoses for cracks or other
faults.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Troubleshooting Cruise Control
Step 5 Use a hand-operated vacuum pump and check
that the vacuum servo unit can hold vacuum without
leaking.
Step 6 Check the servo solenoids for proper operation,
including a resistance measurement check.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CRUISE CONTROL
Troubleshooting Cruise Control
FIGURE 25-6 A cruise control symptom-based chart.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED REAR-WINDOW DEFOGGERS
• The rear-window
defogger system is
controlled by a
driver-operated
switch and a timer
relay.
FIGURE 25-7 A switch and relay control current
through the heating grid of a rear-window
defogger.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED REAR-WINDOW DEFOGGERS
Troubleshooting a Heated Rear-Window Defogger
• A voltmeter can be used to test the operation of the rear
window defogger grid.
FIGURE 25-8 Checking a rearwindow defogger grid with a
voltmeter. As the voltmeter positive
lead is moved along the grid (on the
inside of the vehicle), the voltmeter
reading should steadily decrease as
the meter approaches the ground
side of the grid.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED REAR-WINDOW DEFOGGERS
Troubleshooting a Heated Rear-Window Defogger
• If there is a broken
grid wire, it can be
repaired using an
electrically
conductive
substance available
in a repair kit.
FIGURE 25-9 The typical repair material
contains conductive silver-filled polymer, which
dries in about 10 minutes and is usable in about
30 minutes.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HOMELINK GARAGE DOOR OPENER
• The typical vehicle garage door opening system has
three buttons that can be used to operate one or
more of the following devices.
1. Garage doors equipped with a radio transmitter electric
garage door opener
2. Gates
3. Entry door locks
4. Lighting or small appliances
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HOMELINK GARAGE DOOR OPENER
• The devices include both fixed-frequency
devices, usually older units, and rolling
(encrypted) code devices.
FIGURE 25-10 A typical HomeLink garage door
opener buttons. Notice that three different units
can be controlled from the vehicle using the
HomeLink system.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HOMELINK GARAGE DOOR OPENER
Programming a Vehicle Garage Door Opener
• The steps involved in programming HomeLink in the
vehicle to the garage door opener are as follows:
Step 1 Unplug the garage door opener during
programming to prevent it from being cycled on and off,
which could damage the motor.
Step 2 Check that the frequency of the handheld
transmitter is between 288 and 418 MHz.
Step 3 Install new batteries in the transmitter to be
assured of a strong signal being transmitted to the
HomeLink module in the vehicle.
Step 4 Turn the ignition on, engine off (KOEO).
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HOMELINK GARAGE DOOR OPENER
Programming a Vehicle Garage Door Opener
Step 5 While holding the transmitter 4 to 6 in. (10-15 cm)
away from the HomeLink button, press and hold the
HomeLink button while pressing and releasing the handheld
transmitter every two seconds. Continue pressing and
releasing the transmitter until the indicator light near the
HomeLink button changes from slow blink to a rapid flash.
Step 6 Verify that the vehicle garage door system (HomeLink) button has been programmed. Press and hold the
garage door button. If the indicator light blinks rapidly for two
seconds and then comes on steady, the system has been
successfully programmed using a rolling code design. If the
indicator light is on steady, then it has been successfully
programmed to a fixed-frequency device.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HOMELINK GARAGE DOOR OPENER
Diagnosis and Service
• If a fault occurs with the HomeLink system, first
verify that the garage door opener is functioning
correctly.
• If the problem still exists, attempt reprogramming of
the HomeLink vehicle system being sure that the
remote has a new, recently purchased battery.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
• The up-and down motion of the individual window
motors is controlled by double-pole, double-throw
(DPDT) switches.
• These DPDT switches have five contacts and
permit battery voltage to be applied to the power
window motor, as well as reverse the polarity and
direction of the motor.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
FIGURE 25-11 A typical power
window circuit using PM
motors. Control of the direction
of window operation is
achieved by directing the
polarity of the current through
the nongrounded motors. The
only ground for the entire
system is located at the
master control (driver’s side)
switch assembly.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
FIGURE 25-12 (a) This independent (driver’s door) power window switch plate looks like a
normal simple switch until you turn it over. (b) Notice that this power window contains a large
integrated circuit with a lot of other electronic components to operate the express up and
express down.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
• The window regulator is
attached to the door
glass and controls
opening and closing of
the glass.
• Door glass adjustments
such as glass tilt and
upper and lower stops
are usually the same for
both power and manual
windows.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 25-13 An electric motor and a regulator
assembly raises and lowers the glass on a
power window.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
Troubleshooting Power Windows
• The direction wires and the motor must be
electrically connected to permit operation and
change of direction of the electric lift motor in the
door.
1. If both rear door windows fail to operate from the
independent switches, check the operation of the window
lockout (if the vehicle is so equipped) and the master
control switch.
2. If one window can move in one direction only, check for
continuity in the control wires (wires between the
independent control switch and the master control
switch).
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER WINDOWS
Troubleshooting Power Windows
3. If all windows fail to work or fail to work occasionally,
check, clean, and tighten the ground wire(s) located either
behind the driver’s interior door panel or under the dash
on the driver’s side. A defective fuse or circuit breaker
could also cause all the windows to fail to operate.
4. If one window fails to operate in both directions, the
problem could be a defective window lift motor. The
window could be stuck in the track of the door, which
could cause the circuit breaker built into the motor to open
the circuit to protect the wiring, switches, and motor from
damage.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER SEATS
• A typical poweroperated seat includes
a reversible electric
motor and a
transmission assembly
that has three
solenoids and six drive
cables that turn the six
seat adjusters.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 25-14 A typical power seat
transmission assembly. Even though many of
these units can be disassembled, they are
designed to be replaced as an assembly if any
part inside is defective.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER SEATS
• A screw jack
assembly is often
called a gear nut and is
used to move the front
or back of the seat
cushion up and down.
FIGURE 25-15 This power seat motor assembly
houses three armatures to provide six way
adjustment. Many power seats use one motor
and a transmission assembly to operate the
various gear nuts needed to move the seat.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER SEATS
• Most power seats use a permanent magnet motor
that can be reversed by simply reversing the
polarity of the current sent to the motor by the seat
switch.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER SEATS
FIGURE 25-16
Typical power seat
circuit diagram.
Notice that each
motor has a built-in
electronic (solidstate) PTC circuit
protector. The seat
control switch can
change the
direction in which
the motor(s) runs
by reversing the
direction in which
the current flows
through the motor.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
POWER SEATS
Troubleshooting Power Seats
• If a power seat does not operate or make any noise, the
circuit breaker (or fuse, if the vehicle is so equipped) should
be checked first.
Step 1 Check the circuit breaker, usually located on the fuse panel,
using a test light. The test light should light on both sides of the circuit
breaker even with the ignition off. If the seat relay clicks, the circuit
breaker is functioning, but the relay or electric motor may be
defective.
Step 2 Remove the screws or clips that retain the controls to the
inner door panel or seat and check for voltage at the seat control.
Step 3 Also check the ground connection(s) at the transmission and
clutch control solenoids (if equipped). The solenoids must be properly
grounded to the vehicle body for the power seat circuit to operate.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICALLY HEATED SEATS
Parts and Operation
• Heated seats use heating elements in the seat
bottom, as well as in the seat back in many
vehicles.
• Some vehicles are equipped with heated seats in
both the rear, and front seats.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICALLY HEATED SEATS
Diagnosis and Service
• Most vehicle
manufacturers
recommend replacing
the entire heating
element if it is
defective.
FIGURE 25-17 The heating wires of a heated
seat are a replaceable part, but service requires
that the upholstery be removed.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED AND COOLED SEATS
Parts and Operation
• Most electrically heated and cooled seats use a
thermoelectric device (TED) located under the
seat cushion and seat back.
• When the heated and cooled seats are turned on,
air is forced through a filter and then through the
thermoelectric modules.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED AND COOLED SEATS
Diagnosis and Service
• A partially clogged filter can restrict airflow and
reduce the heating or cooling effect.
• If the system control indicator light is not on or the
system does not work at all, check for power and
ground at the thermoelectric devices.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED STEERING WHEEL
Parts Involved
• A heated steering wheel usually consists of the
following components.
– Steering wheel with a built-in heater in the rim
– Heated steering wheel control switch
– Heated steering wheel control module
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED STEERING WHEEL
Operation
• When the steering
wheel heater control
switch is turned on, a
signal is sent to the
control module and
electrical current flows
through the heating
element in the rim of
the steering wheel.
FIGURE 25-18 The heated steering wheel is
controlled by a switch on the steering wheel on
this vehicle.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
HEATED STEERING WHEEL
Diagnosis and Service
• If the heated steering wheel is not working, follow
the service information testing procedures which
would include a check of the following:
1. Check the heated steering wheel control switch for
proper operation. This is usually done by checking for
voltage at both terminals of the switch.
2. Check for voltage and ground at the terminals leading
to the heating element. If voltage is available at the
heating element and the ground has less than 0.2 volt
drop to a good chassis ground, the heating element is
defective.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRIC POWER DOOR LOCKS
• Most electric door locks use a permanent magnet
(PM) reversible electric motor that operates the
lock-activating rod.
• PM reversible motors do not require grounding
because, as with power windows, the motor control
is determined by the polarity of the current through
the two motor wires.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRIC POWER DOOR LOCKS
FIGURE 25-19 A typical
electric power door lock
circuit diagram. Note
that the control circuit is
protected by a fuse,
whereas the power
circuit is protected by a
circuit breaker. As with
the operation of power
windows, power door
locks typically use
reversible PM
nongrounded electric
motors. These motors
are geared
mechanically to the lockunlock mechanism.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
• Even though some
Ford vehicles use a
keypad located on the
outside of the door,
most keyless entry
systems use a wireless
transmitter built into the
key or key fob.
FIGURE 25-20 A typical keyless remote fob. A
fob is a term used to describe a key ring.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
• The transmitter broadcasts a signal that is received by the
electronic control module, which is generally mounted in
the trunk or under the instrument panel.
FIGURE 25-21 A
typical vehicle showing
the location of the
various components of
the remote keyless
entry system.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
Rolling Code Reset Procedure
• A rolling code type of transmitter emits a different
frequency every time the transmitter button is
depressed and then rolls over to another frequency
so that it cannot be intercepted.
• If the transmitter does not work, try to resynchronize
the transmitter to the receiver by depressing and
holding both the lock and the unlock button for 10
seconds when within range of the receiver.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
Keyless Entry Diagnosis
• If the keyless entry system fails to operate after the
transmitter battery has been replaced, check the
following items.
–
–
–
–
–
–
Mechanical binding in the door lock
Low vehicle battery voltage
Blown fuse
Open circuit to the control module
Defective control module
Defective transmitter
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
Programming a New Remote
• A typical reprogramming sequence for a
Honda/Acura includes the following steps.
Step 1 Turn the ignition switch to on.
Step 2 Within four seconds, push the transmitter lock or
unlock button with the transmitter aimed at the receiver in
the passenger’s multiplex control unit.
Step 3 Within four seconds, turn the ignition switch to off.
Step 4 Within four seconds, turn the ignition switch to on.
Step 5 Repeat steps 2, 3, and 4 two more times.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
KEYLESS ENTRY
Programming a New Remote
Step 6 Confirm you can hear the sound of the door lock
actuators. Within four seconds, push the transmitter lock or
unlock button again. The keyless receiver is now in the
programming mode. You must push the transmitter lock or
unlock button of the first transmitter again to program that
transmitter.
Step 7 Within 10 seconds, aim the transmitters (up to three)
whose codes you want to store at the receiver, and press the
transmitter lock or unlock buttons. Confirm that you can hear
the sound of the door lock actuators after each transmitter
code is stored.
Step 8 Turn the ignition switch off, and pull out the key.
Step 9 Confirm the proper operation with the new codes(s).
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
• Anti-theft devices flash
lights or sound an alarm if
the vehicle is broken into or
vandalized.
• Some anti-theft systems
are more complex and also
have electronic sensors
that trigger the alarm if
there is a change in battery
current draw, a violent
vehicle motion, or if glass is
broken.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 25-22 A typical shock sensor used
in alarm and antitheft systems. If the vehicle
is moved, the magnet will move relative to
the coil inducing a small voltage, which will
trigger the alarm.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Anti-Theft System Diagnosis
• Modern anti-theft systems, especially those
supplied as original equipment, are electronically
regulated and have a self-diagnostic program.
• Diagnostic and test procedures are similar as for
any of the other electronic control systems used on
the vehicle.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Anti-Theft System Testing and Service
• Before performing any diagnostic checks, make
sure that all of the following electrical devices
function correctly.
–
–
–
–
Parking and low-beam headlights
Dome and courtesy lights
Horn
Electric door locks
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Anti-Theft System Testing and Service
• If all of the previously
mentioned devices are
operational, check all
the circuits leading to
the anti-theft control
module.
• Doorjamb switches
complete the ground
circuit when a door is
FIGURE 25-23 Door switches, which
opened.
complete the ground circuit with the door
open, are a common source of high
resistance.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Chrysler Remote Keyless Entry System
• Beginning in 1998, Chrysler started a security
system known as the Sentry Key Immobilizer
System (SKIS).
• When an attempt to start a vehicle arises, the
onboard computer sends out a radio-frequency (RF)
signal that is read by the electronic transponder
chip embedded in the key.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Chrysler Self-Programming Additional Sentry Keys
(requires two original keys)
Step 1 Purchase a blank key and have it cut to fit
the lock cylinder.
Step 2 Insert original key 1 into the ignition and turn
to on.
Step 3 Wait five seconds and turn the key to off.
Step 4 Immediately insert original key 2 into the
ignition and turn to on.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Chrysler Self-Programming Additional Sentry Keys
Step 5 Wait 10 seconds for the SKIS indicator in the
dash to start to flash.
Step 6 Turn the ignition off, insert the new blank
key, and turn the ignition back on.
Step 7 Once the SKIS light stops flashing and turns
off, your new key is programmed.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Ford PATS System
• Ford uses a responder key for its anti-theft system,
which is called the Passive Anti-Theft System
(PATS).
• There is a computer chip inside the key and without
it, the vehicle will not start even though the key may
work in the lock cylinder.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Ford Programming for Additional (PATS) Keys
• This procedure will only work if two or more
programmed ignition keys are available. The steps
are as follows:
Step 1 Insert the first programmed ignition key into the
ignition lock cylinder. Turn the ignition switch from the lock
to run position (ignition switch must stay in the run
position for one second). Turn the ignition switch to the
lock position and remove the ignition key from the ignition
lock cylinder.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Ford Programming for Additional (PATS) Keys
Step 2 Within five seconds of turning the ignition switch to
the lock position, insert the second programmed ignition
key into the ignition lock cylinder. Turn the ignition switch
from the lock to run position (ignition switch must stay in
the run position for one second). Turn the ignition switch
to the lock position and remove the second ignition key
from the ignition lock cylinder.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
Ford Programming for Additional (PATS) Keys
Step 3 Within five seconds of turning the ignition switch to
the lock position, insert a new unprogrammed ignition key
into the ignition lock cylinder. Turn the ignition switch from
the lock to run position (the ignition switch must stay in
the run position for one second). Turn the ignition switch
to the lock position and remove the ignition key from the
ignition lock cylinder. The new ignition key should now be
programmed. To program additional key(s), repeat the
key programming procedure from step 1.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
General Motors Anti-Theft System
• The types of anti-theft
systems used on General
Motors vehicles have
varied, starting with one
that used a resistor pellet in
the ignition key.
• A special tester was
required to test this system.
FIGURE 25-24 A special tool is needed to
diagnose a General Motors VATS security
system and special keys that contain a resistor
pellet.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ANTI-THEFT SYSTEMS
General Motors Anti-Theft System
• Newer systems include the
Passkey I and Passkey II,
which also use a resistor
pellet in the ignition key.
Passlock I, Passlock II,
and Passlock truck
systems use a Hall-effect
sensor and magnets in the
lock cylinder with a
conventional key.
FIGURE 25-25 The Passlock series of General
Motors security systems use a conventional key.
The magnet is located in the ignition lock
cylinder and triggers the Hall-effect sensors.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICAL ACCESSORY SYMPTOM GUIDE
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICAL ACCESSORY SYMPTOM GUIDE
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICAL ACCESSORY SYMPTOM GUIDE
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICAL ACCESSORY SYMPTOM GUIDE
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
ELECTRICAL ACCESSORY SYMPTOM GUIDE
FIGURE 25-26 Corrosion or faults at the
junction between the wiring and the rearwindow electrical grid are the source of
many rear-window defogger problems.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SUMMARY
1. Most power windows and power door locks use a
permanent magnet motor that has a built-in circuit breaker
and is reversible. The control switches and relays direct the
current through the motors.
2. The current flow through a rear-window defogger is often
self-regulating. As the temperature of the grid increases, its
resistance increases, reducing current flow. Some rear
window defoggers are also used as radio antennas.
3. Remote keyless entry systems use a wireless transmitter
built into the key fob to operate the power door lock.
4. Factory anti-theft systems must function properly to allow
the engine to crank and/or start.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
REVIEW QUESTIONS
1. Describe how power door locks on a four-door vehicle can
function with only one ground wire connection.
2. Explain how a rear-window defogger can regulate how
much current flows through the grids based on
temperature.
3. What is the usual procedure to follow to resynchronize a
remote keyless entry transmitter?
4. Which anti-theft system(s) uses a resistor pellet in the
ignition key?
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
1. The owner of a vehicle equipped with cruise
control complains that the cruise control often
stops working when driving over rough or bumpy
pavement. Technician A says the brake switch may
be out of adjustment. Technician B says a
defective servo unit is the most likely cause. Which
technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
1. The owner of a vehicle equipped with cruise
control complains that the cruise control often
stops working when driving over rough or bumpy
pavement. Technician A says the brake switch may
be out of adjustment. Technician B says a
defective servo unit is the most likely cause. Which
technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
2. Technician A says that the cruise control on a
vehicle that uses an electronic throttle control
(ETC) system uses a servo to move the throttle.
Technician B says that the cruise control on a
vehicle with ETC uses the APP sensor to set the
speed. Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
2. Technician A says that the cruise control on a
vehicle that uses an electronic throttle control
(ETC) system uses a servo to move the throttle.
Technician B says that the cruise control on a
vehicle with ETC uses the APP sensor to set the
speed. Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
3. All power windows fail to operate from the
independent switches but all power windows
operate from the master switch. Technician A says
the window lockout switch may be on. Technician
B says the power window relay could be defective.
Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
3. All power windows fail to operate from the
independent switches but all power windows
operate from the master switch. Technician A says
the window lockout switch may be on. Technician
B says the power window relay could be defective.
Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
4. Technician A says that a defective ground
connection at the master control switch (driver’s
side) could cause the failure of all power windows.
Technician B says that if one control wire is
disconnected, all windows will fail to operate.
Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
4. Technician A says that a defective ground
connection at the master control switch (driver’s
side) could cause the failure of all power windows.
Technician B says that if one control wire is
disconnected, all windows will fail to operate.
Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
5. A typical six-way power seat _____.
a) Uses six separate PM nongrounded electric
motors
b) Uses one or three motors (depending on the
manufacturer)
c) Uses six separate grounded electric motors only
d) Uses two electric motors and a three-way directacting solenoid-controlled transmission device
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
5. A typical six-way power seat _____.
a) Uses six separate PM nongrounded electric
motors
b) Uses one or three motors (depending on the
manufacturer)
c) Uses six separate grounded electric motors only
d) Uses two electric motors and a three-way directacting solenoid-controlled transmission device
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
6. When checking the operation of a rear-window
defogger with a voltmeter, _____.
a) The voltmeter should be set to read AC volts
b) The voltmeter should read close to battery voltage
anywhere along the grid
c) Voltage should be available anytime at the power side of
the grid because the control circuit just completes the
ground side of the heater grid circuit
d) The voltmeter should indicate decreasing voltage when
the grid is tested across the width of the glass
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
6. When checking the operation of a rear-window
defogger with a voltmeter, _____.
a) The voltmeter should be set to read AC volts
b) The voltmeter should read close to battery voltage
anywhere along the grid
c) Voltage should be available anytime at the power side of
the grid because the control circuit just completes the
ground side of the heater grid circuit
d) The voltmeter should indicate decreasing voltage when
the grid is tested across the width of the glass
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
7. PM motors used in power windows, mirrors,
and seats can be reversed by _____.
a)
b)
c)
d)
Sending current to a reversed field coil
Reversing the polarity of the current to the motor
Using a reverse relay circuit
Using a relay and a two-way clutch
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
7. PM motors used in power windows, mirrors,
and seats can be reversed by _____.
a)
b)
c)
d)
Sending current to a reversed field coil
Reversing the polarity of the current to the motor
Using a reverse relay circuit
Using a relay and a two-way clutch
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
8. If only one power door lock is inoperative, a
possible cause is _____.
a) A poor ground connection at the power door
lock relay
b) A defective door lock motor (or solenoid)
c) A defective (open) circuit breaker for the power
circuit
d) A defective (open) fuse for the control circuit
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
8. If only one power door lock is inoperative, a
possible cause is _____.
a) A poor ground connection at the power door
lock relay
b) A defective door lock motor (or solenoid)
c) A defective (open) circuit breaker for the power
circuit
d) A defective (open) fuse for the control circuit
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
9. A keyless remote control stops working. Technician
A says the battery in the remote could be dead.
Technician B says that the key fob may have to be
resynchronized. Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
9. A keyless remote control stops working. Technician
A says the battery in the remote could be dead.
Technician B says that the key fob may have to be
resynchronized. Which technician is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
10. Two technicians are discussing anti-theft systems.
Technician A says that some systems require a
special key. Technician B says that some systems
use a computer chip in the key. Which technician
is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHAPTER QUIZ
10. Two technicians are discussing anti-theft systems.
Technician A says that some systems require a
special key. Technician B says that some systems
use a computer chip in the key. Which technician
is correct?
a)
b)
c)
d)
Technician A only
Technician B only
Both Technicians A and B
Neither Technician A nor B
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
END
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458