Download generator (alternator) overhaul

OBJECTIVES
After studying Chapter 21, the reader should be able to:
1. Prepare for ASE Electrical/Electronic Systems (A6)
certification test content area “D” (Charging System
Diagnosis and Repair).
2. Discuss the various generator test procedures.
3. Explain how to disassemble a generator and test its
component parts.
4. Discuss how to check the wiring from the generator to the
battery.
5. Describe how to test the operation of a computer-controlled
charging 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
CHARGING SYSTEM TESTING AND SERVICE
• The charging system can be tested as part of a routine
vehicle inspection or to determine the reason for a no-charge
or reduced-charging circuit performance.
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
CHARGING SYSTEM TESTING AND SERVICE
Charging Voltage Test
Step 1 Select DC volts.
Step 2 Connect the red meter lead to the positive (+)
terminal of the battery and the black meter lead to the
negative (-) terminal of the battery.
Step 3 Start the engine and increase the engine speed to
about 2000 RPM (fast idle) and record the charging voltage.
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
CHARGING SYSTEM TESTING AND SERVICE
Charging Voltage Test
FIGURE 21-1 The digital multimeter should be
set to read DC volts, with the red lead connected
to the positive (+) battery terminal and the black
meter lead connected to the negative (-) battery
terminal.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-2 A scan tool such as this
Chrysler DRB III can be used to check
the generator output voltage.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHARGING SYSTEM TESTING AND SERVICE
Magnetized Rear Bearing Test
• With the engine running,
use a screwdriver or other
metallic object to test for
magnetism at the rear
bearing of the generator.
FIGURE 21-3 If the rear bearing is magnetized,
the voltage regulator, generator brushes, and
rotor are functioning.
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
CHARGING SYSTEM TESTING AND SERVICE
Magnetized Rear Bearing Test
• If the rear bearing is magnetized, then the following facts are
known.
1. The voltage regulator is working.
2. The generator brushes are working.
3. The rotor in the generator is producing a magnetic field.
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
CHARGING SYSTEM TESTING AND SERVICE
Magnetized Rear Bearing Test
• If the rear bearing is not magnetized, then one or more of the
following problems exist.
1. The voltage regulator is not working.
2. The generator brushes are worn or stuck, and they are not making
good electrical contact with the rotor slip rings.
3. The generator rotor could be 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
CHARGING SYSTEM TESTING AND SERVICE
Full-Fielding Test
• If the rear bearing is not magnetized, then a procedure for
bypassing the voltage regulator should be used to determine
if the generator is capable of producing its designed output.
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
CHARGING SYSTEM TESTING AND SERVICE
Full-Fielding Test
FIGURE 21-4 A GM generator with an internal
voltage regulator can be identified by the
horizontal plug-in connector.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-5 Connections required to fullfield a GM generator with an external voltage
regulator.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHARGING SYSTEM TESTING AND SERVICE
Full-Fielding Test
FIGURE 21-6 Connections required to
full-field a Ford generator with an external
voltage regulator.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-7 Jumper wire connections required
to full-field a Ford (or Leece-Neville) generator
with an internal electronic voltage regulator.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
CHARGING SYSTEM TESTING AND SERVICE
Full-Fielding Test
FIGURE 21-8 Wiring diagram of a Ford integral generator or regulator (IAR) 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
CHARGING SYSTEM TESTING AND SERVICE
Full-Fielding Test
FIGURE 21-9 Connections required to fullfield a Chrysler generator with a
mechanical voltage regulator.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-10 Connections required
to full-field a Chrysler generator with
an electronic voltage regulator.
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
THE LIGHTER PLUG TRICK
• Simply construct a test tool
using a lighter plug at one
end of a length of twoconductor wire and the
other end connected to a
double banana plug.
FIGURE 21-11 Charging system voltage can be
easily checked at the lighter plug by connecting
a lighter plug to the voltmeter through a double
banana plug.
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 A TEST LIGHT TO CHECK FOR A DEFECTIVE
FUSIBLE LINK
• A quick and easy test to
check if the fusible link is
okay is to touch a test light
to the output terminal.
• This test confirms that the
circuit between the AC
generator and the battery
has continuity.
FIGURE 21-12 Before replacing a generator
(alternator), the wise technician checks that
battery voltage is present at the output and
battery voltage sense terminals.
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
ACCESSORY DRIVE BELT INSPECTION
• When a belt that turns the
water pump breaks, the
engine could rapidly
overheat, causing serious
engine damage, and if one
belt breaks, it often causes
the other belts to become
tangled, causing them to
break.
FIGURE 21-13 This accessory drive belt should
be replaced because it has many cracks. The
usual specification for when a serpentine belt
requires replacement is when there are three or
more cracks in any one rib in any 3 in. length.
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
ACCESSORY DRIVE BELT INSPECTION
Tension Measurement
• There are four ways that vehicle manufacturers specify that
the belt tension is within factory specifications.
1. Belt tension gauge
2. Marks on a tensioner
3. Torque wrench reading
4. Deflection
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
AC VOLTAGE CHECK
• The procedure to check for AC voltage, called ripple
voltage, includes the following steps.
Step 1 Set the digital meter to read AC volts.
Step 2 Start the engine and operate it at 2000 RPM (fast idle).
Step 3 Connect the voltmeter leads to the positive and negative
battery terminals.
Step 4 Turn on the headlights to provide an electrical load on the
generator.
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
AC VOLTAGE CHECK
• A higher, more accurate reading can be obtained by
touching the meter lead to the output terminal of the
generator.
FIGURE 21-14 AC ripple at the
output terminal of the generator is
more accurate than testing at the
battery due to the resistance of the
wiring between the generator and
the battery. The reading shown on
the meter is only 78 mV
(0.078V),far below what the reading
would be if a diode were defective.
(Courtesy of Fluke Corporation)
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
THE MINI CLAMP ON DMM TEST
• The generator output can
be easily measured using a
mini clamp-on-type digital
multimeter.
• A reading of greater than
10 amperes AC indicates
defective generator diodes.
FIGURE 21-15 A mini clamp-on digital
multimeter can be used to measure generator
output. This meter was set on the 200-A DC
scale. With the engine running and all lights and
accessories on, the generator was able to
produce almost exactly its specified rating of 105
A.
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
AC CURRENT RIPPLE CHECK
• To measure the AC ripple current to the battery, perform the
following steps.
Step 1 Start the engine and turn on the lights to create an electrical
load on the generator.
Step 2 Using a clamp-on meter, place the clamp around either all of
the positive (+) battery cables or all of the negative (-) battery cables.
Step 3 Read the meter display and determine the needed service.
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
CHARGING SYSTEM VOLTAGE DROP TESTING
• When there is a suspected charging system problem (with or
without a charge indicator light on), simply follow these steps
to measure the voltage drop of the insulated (powerside)
charging circuit.
Step 1 Start the engine and run it at a fast idle (about 2000 engine
RPM).
Step 2 Turn on the headlights to ensure an electrical load on the
charging system.
Step 3 Using any voltmeter, connect the positive test lead
(usually red) to the output terminal of the generator. Attach the
negative test lead (usually black) to the positive post of the 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
CHARGING SYSTEM VOLTAGE DROP TESTING
• The results should be interpreted as follows:
1. If there is less than a 0.4 volt reading, then all wiring and
connections are satisfactory.
2. If the voltmeter reads higher than 0.4 volt, there is excessive
resistance (voltage drop) between the generator
output terminal and the positive terminal of the battery.
3. If the voltmeter reads battery voltage (or close to battery voltage),
there is an open circuit between the battery and the generator output
terminal.
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
CHARGING SYSTEM VOLTAGE DROP TESTING
• If the reading is over
0.2 volt, connect one
end of an auxiliary
ground wire to the
case of the generator
and the other end to a
good engine ground.
FIGURE 21-16 Voltmeter hookup to test the
voltage drop of the charging 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
GENERAL MOTORS SI TEST LIGHT TEST
• All General Motors System
Integration (SI) (internal
voltage regulator) series
Delcotron generators
(alternators) can be easily
tested using a standard 6 to
12 volt test light.
FIGURE 21-17 Typical GM SI generator. Note
the location and wire color used for terminals 1
and 2.
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
GENERAL MOTORS SI TEST LIGHT TEST
Normal Operation
• The following steps outline the procedure for testing an SI
series generator for normal operation.
Step 1 With the ignition on (engine off), a test light should
be bright if touched to the “BAT” terminal and terminal 2.
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
GENERAL MOTORS SI TEST LIGHT TEST
Normal Operation
Step 2 With the engine running, touching any of the three
terminals should produce a bright test light. The BAT
terminal and terminal 2 should both cause a bright light
because both are battery voltage sources. Terminal 1
should also light the test light brightly because when the
generator is producing a current, the internal voltage rises
and applies an opposing voltage on the dash light bulb,
which causes current to stop flowing through the bulb and
the charge light to go out.
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
GENERAL MOTORS SI TEST LIGHT TEST
Problems and Possible Causes
• If the test light is not on at all on terminal 1 (brown or tan
wire), the problem is an open circuit in the wiring between
the dash and the generator.
• If the test light does not light on either the BAT terminal or
terminal 2, an open circuit exists between the positive post of
the battery and the generator.
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
GENERAL MOTORS CS SERIES AC GENERATORS
• The CS series generators are designed to operate as
stand-alone generators or be controlled by a vehicle
computer system.
FIGURE 21-18 Typical GM CS generator wiring
plug identification. Note that terminal F is
sometimes terminal I on some generators.
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
DIAGNOSING PROBLEMS WITH THE GENERAL
MOTORS CS SERIES
• If the charge indicator light is on in the dash, unplug the
connector (which can have up to four wires connected).
• Check all fuses, all fusible links, and the charge light
indicator bulb.
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
GENERATOR OUTPUT TEST
• A generator (alternator) output test measures the current
(amperes) of the alternator.
FIGURE 21-19 Typical
hookup of a starting and
charging tester.
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
GENERATOR OUTPUT TEST
• The testing procedure for generator output is as
follows:
Step 1 Connect the starting and charging test leads
according to the manufacturer’s instructions.
Step 2 Turn the ignition switch on (engine off) and
observe the ammeter. This is the ignition circuit current,
and it should be about 2 to 8 amperes.
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
GENERATOR OUTPUT TEST
Step 3 Start the engine and operate it at 2000 RPM (fast idle). Turn
the load increase control slowly to obtain the highest reading on the
ammeter scale. Note the ampere reading.
Step 4 Total the amperes from steps 2 and 3. Results should be
within 10% (or 15 amperes) of the rated output. Rated output may be
stamped on the generator.
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
GENERATOR OUTPUT TEST
FIGURE 21-20 The output rating on the
General Motors generator (alternator) is
stamped into the case.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-21 The output on this generator
is printed on a label.
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HOW TO DETERMINE MINIMUM REQUIRED
GENERATOR OUTPUT
• After connecting an ammeter correctly in the battery circuit,
continue as follows:
1. Start the engine and operate to about 2000 RPM (fast idle).
2. Turn the heat selector to air conditioning (if the vehicle is so
equipped).
3. Turn the blower motor to high speed.
4. Turn the headlights on bright.
5. Turn on the radio.
6. Turn on the windshield wipers.
7. Turn on any other accessories that may be used continuously (do
not operate the horn, power door locks, or other units that are not
used for more than a few seconds).
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
HOW TO DETERMINE MINIMUM REQUIRED
GENERATOR OUTPUT
• If using an inductive-pickup
ammeter, be certain that
the pickup is over all the
wires leaving the battery
terminal.
FIGURE 21-22 When connecting an inductive
ammeter probe, be certain that the pickup is
over all wires. The probe will work equally well
over either all positive or all negative cables
because all current leaving a battery must
return.
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
HOW TO DETERMINE MINIMUM REQUIRED
GENERATOR OUTPUT
FIGURE 21-23 A diagram showing the location of the charging system wiring of a
typical vehicle. The best location to use to check for the generator alternator)
output is at the output wire from the B+ (BAT) terminal. Notice that the generator
supplies all electrical needs of the vehicle first, then charges the battery if
needed.
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
HOW TO DETERMINE MINIMUM REQUIRED
GENERATOR OUTPUT
• Most vehicles that use a computer-controlled charging
system can be diagnosed with a scan tool.
• Not only can the charging voltage be monitored, but in many
vehicles, the field circuit can be controlled and the output
voltage monitored to check that the system is operating
correctly.
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
GENERATOR (ALTERNATOR) REMOVAL
• A typical removal procedure includes the following steps.
Step 1 Before disconnecting the negative battery cable, use a test
light or a voltmeter and check for battery voltage at the output
terminal of the generator. A complete circuit must exist between the
generator and the battery. If there is no voltage at the generator
output terminal, check for a blown fusible link or other electrical circuit
fault.
Step 2 Disconnect the negative (0) terminal from the battery.
Step 3 Remove the accessory drive belt that drives the generator.
Step 4 Remove the fasteners and brackets, as necessary, and
remove the generator from 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
GENERATOR DISASSEMBLY
• If testing has confirmed that
there are generator
problems, remove the
generator from the vehicle
after disconnecting the
negative battery cable.
• Mark the case with a
scratch or with chalk to
ensure proper reassembly
of the generator case.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-24 Always mark the case of the
generator before disassembly to be assured of
correct reassembly.
© 2010 Pearson Higher Education, Inc.
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WHAT IS A “CLOCK POSITION”?
• Most generators of a particular manufacturer can be used on a
variety of vehicles, which may require wiring connections
placed in various locations.
• The four through bolts that hold the two halves together are
equally spaced; therefore, the rear generator housing can be
installed in any one of four positions to match the wiring needs
of various models.
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
WHAT IS A “CLOCK POSITION”?
FIGURE 21-25 Explanation of clock
positions. Because the four through
bolts are equally spaced, it is possible
for a generator to be installed in one of
four different clock positions. The
connector position is determined by
viewing the generator from the diode
end with the threaded adjusting lug in
the up or 12 o’clock position. Select the
3 o’clock, 6 o’clock, 9 o’clock, or 12
o’clock position to match the unit being
replaced.
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
TESTING THE ROTOR
• Typical resistance values include the following:
– GM: 2.4 to 3.5 ohms
– Ford: 3.0 to 5.5 ohms
– Chrysler: 3.0 to 6.0 ohms
• Ohmmeters can also vary in accuracy.
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
TESTING THE ROTOR
FIGURE 21-26 Testing a
generator rotor using an
ohmmeter.
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
TESTING THE STATOR
• There should not be
continuity (in other words,
there should be infinity
ohms, or the test light
should not light) when the
stator is tested between
any stator lead and the
metal stator core.
FIGURE 21-27 If the ohmmeter reads infinity between
any two of the three stator windings, the stator is open
and, therefore, defective. The ohmmeter should read
infinity between any stator lead and the steel
laminations. If the reading is less than infinity, the stator
is grounded. Stator windings can be tested if shorted
because the normal resistance is very low.
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
TESTING THE STATOR
• An ohmmeter cannot detect
an open stator if the stator
is delta wound.
• The ohmmeter will still
indicate low resistance
because all three windings
are electrically connected.
FIGURE 21-28 An open in a deltawound stator cannot be detected using
an ohmmeter.
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
TESTING THE DIODE TRIO
• Many generators are
equipped with a diode trio.
• Because trio means “three,”
a diode trio is three diodes
connected together.
FIGURE 21-29 Typical diode trio. If one leg of a
diode trio is open, the generator may produce
close to normal output, but the charge indicator
light on the dash will be on dimly. The plus signs
indicate the anodes, and the minus sign
indicates the cathode terminal of the diodes.
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
TESTING THE RECTIFIER BRIDGE (DIODES)
• To test many generator diodes, it may be necessary to
unsolder the stator connections.
FIGURE 21-30 A GM rectifier bridge that has
been disassembled to show the individual
diodes.
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
TESTING THE RECTIFIER BRIDGE (DIODES)
• General Motors generators
use a replaceable rectifier
bridge containing all six
diodes in one unit
combined with a finned
heat sink.
• Some Ford and other
generators also use six
diodes in a single
replaceable bridge.
FIGURE 21-31 Diodes being soldered to the
stator on a Ford generator.
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
TESTING THE GM INTERNAL VOLTAGE
REGULATOR
• Even though the voltage
regulator can be tested on
the vehicle with the engine
running, the internal voltage
regulator can also be tested
using a special tester.
FIGURE 21-32 Testing a GM SI internal
voltage regulator using a voltage regulator
tester. This tester can be used to test most
internal and external electronic voltage
regulators by using the appropriate adapter
harness and test leads.
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
BRUSH HOLDER REPLACEMENT
• After the brushes are
installed (usually retained
by two or three screws) and
the rotor is installed in the
generator housing, a brush
retainer pin can be pulled
out through an access hole
in the rear of the generator,
allowing the brushes to be
pressed against the slip
rings by the brush springs.
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
FIGURE 21-33 A brush holder assembly
shown assembled in the generator. The
brush retainer is actually a straightenedout paper clip.
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BEARING SERVICE AND REPLACEMENT
• The bearing of a generator must be able to support the rotor
and reduce friction.
• Many generator front bearings must be removed from the
rotor using a special puller.
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
GENERATOR ASSEMBLY
• After testing or servicing, the generator rectifier(s), regulator,
stator, and brush holder must be reassembled.
• The battery terminal should be covered with a plastic or
rubber protective cap to help prevent accidental shorting to
ground, which could seriously damage the generator.
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
REMANUFACTURED GENERATORS
• Remanufactured or rebuilt generators are totally
disassembled and rebuilt.
• Every generator is then assembled and tested for proper
output, boxed, and shipped to a warehouse.
FIGURE 21-34 (a) A generator for a GEO Prism looks like a typical General Motors
CS-130 except for this adapter that converted the Toyota wiring harness to the GM
generator. (b) After removing the adapter, the original generator
connection is visible.
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
GENERATOR (ALTERNATOR) INSTALLATION
• A typical installation procedure includes the
following steps.
Step 1 Verify that the replacement generator is the
correct unit for the vehicle.
Step 2 Install the generator wiring on the generator and
install the generator.
Step 3 Check the condition of the drive belt and replace,
if necessary. Install the drive belt over the drive pulley.
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
GENERATOR (ALTERNATOR) INSTALLATION
Step 4 Properly tension the drive belt.
Step 5 Tighten all fasteners to factory specifications.
Step 6 Double-check that all fasteners are correctly
tightened and remove all tools from the engine
compartment area.
Step 7 Start the engine and verify proper charging circuit
operation.
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
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
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
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
GENERATOR (ALTERNATOR) OVERHAUL
Step-by-Step
Diagnosis and Troubleshooting of Automotive Electrical,
Electronic, and Computer Systems, Fifth Edition
By James D. Halderman
cont
© 2010 Pearson Higher Education, Inc.
Pearson Prentice Hall - Upper Saddle River, NJ 07458
SUMMARY
1.
2.
Charging system testing requires that the battery be at
least 75% charged to be assured of accurate test results.
The charge indicator light should be on with the ignition
switch on, but should go out when the engine is running.
Normal charging voltage (at 2000 engine RPM) is 13.5 to
15.0 volts.
If the charging system is not charging properly, the rear
bearing of the generator should be checked for
magnetism. If the rear bearing is magnetized, the voltage
regulator, brushes, and generator rotor are functioning
correctly. If the rear bearing is not magnetized, the voltage
regulator, generator brushes, or rotor is not functioning.
Bypass the voltage regulator by supplying battery voltage
to the field. If the rear bearing is now magnetized and the
charging system output is normal, the voltage regulator is
at fault.
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
3. To check for excessive resistance in the wiring
between the generator and the battery, a voltage
drop test should be performed.
4. Generators do not produce their maximum-rated
output unless required by circuit demands.
Therefore, to test for maximum generator output,
the battery must be loaded to force the generator
to produce its maximum output.
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
5. Each generator should be marked across its case before
disassembly to ensure proper clock position during
reassembly. After disassembly, all generator internal
components should be tested using a continuity light or an
ohmmeter. The following components should be tested:
a. Stator
b. Rotor
c. Diodes
d. Diode trio (if the generator is so equipped)
e. Bearings
f. Brushes (should be more than 1/2 in. long)
6. Electronic voltage regulators can be tested either off the
vehicle using a special tester or on the vehicle using the
full-field bypass procedure.
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.
2.
3.
Describe how to test the voltage drop of the charging
circuit.
Discuss how to measure the amperage output of a
generator.
Explain what tests can be performed to determine whether
a diode or stator is defective before removing the
generator from 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
CHAPTER QUIZ
1.
To check the charging voltage, connect a digital multimeter
(DMM) to the positive (+) and the negative (-) terminals of
the battery and select _____.
a)
b)
c)
d)
DC volts
AC volts
DC amps
AC amps
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.
To check the charging voltage, connect a digital multimeter
(DMM) to the positive (+) and the negative (-) terminals of
the battery and select _____.
a)
b)
c)
d)
DC volts
AC volts
DC amps
AC amps
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. To check for ripple voltage from the generator,
select _____.
a)
b)
c)
d)
DC volts
AC volts
DC amps
AC amps
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. To check for ripple voltage from the generator,
select _____.
a)
b)
c)
d)
DC volts
AC volts
DC amps
AC amps
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. The maximum allowable AC current in amperes
that is being sent to the battery from the generator
is _____.
a)
b)
c)
d)
0.4 A
1 to 3 A
3 to 4 A
10% of the rated output of the generator
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. The maximum allowable AC current in amperes
that is being sent to the battery from the generator
is _____.
a)
b)
c)
d)
0.4 A
1 to 3 A
3 to 4 A
10% of the rated output of the generator
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. Why should the lights be turned on when checking
for ripple voltage or AC current from the
generator?
a)
b)
c)
d)
To warm the battery
To check that the battery is fully charged
To create an electrical load for the generator
To test the battery before conducting other tests
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. Why should the lights be turned on when checking
for ripple voltage or AC current from the
generator?
a)
b)
c)
d)
To warm the battery
To check that the battery is fully charged
To create an electrical load for the generator
To test the battery before conducting other tests
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. An acceptable charging circuit voltage on a 13 volt
system is _____.
a)
b)
c)
d)
13.5 to 15.0 volts
12.6 to 15.6 volts
12 to 14 volts
14.9 to 16.1 volts
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. An acceptable charging circuit voltage on a 13 volt
system is _____.
a)
b)
c)
d)
13.5 to 15.0 volts
12.6 to 15.6 volts
12 to 14 volts
14.9 to 16.1 volts
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. Technician A says that by full-fielding the
generator, you are bypassing the voltage
regulator. Technician B says that voltage
regulators control the generator output by
controlling the field current through the rotor.
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
6. Technician A says that by full-fielding the
generator, you are bypassing the voltage
regulator. Technician B says that voltage
regulators control the generator output by
controlling the field current through the rotor.
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
7.
Technician A says that a voltage drop test of the charging
circuit should only be performed when current is flowing
through the circuit. Technician B says to connect the leads
of a voltmeter to the positive and negative terminals of the
battery to measure the voltage drop of the charging
system. 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
7.
Technician A says that a voltage drop test of the charging
circuit should only be performed when current is flowing
through the circuit. Technician B says to connect the leads
of a voltmeter to the positive and negative terminals of the
battery to measure the voltage drop of the charging
system. 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
8. When testing a generator rotor, if an ohmmeter
shows zero ohms with one meter lead attached to
the slip rings and the other meter lead touching
the rotor shaft, the rotor is _____.
a)
b)
c)
d)
Okay (normal)
Defective (shorted-to-grounded)
Defective (shorted-to-voltage)
Okay (rotor windings are open)
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. When testing a generator rotor, if an ohmmeter
shows zero ohms with one meter lead attached to
the slip rings and the other meter lead touching
the rotor shaft, the rotor is _____.
a)
b)
c)
d)
Okay (normal)
Defective (shorted-to-grounded)
Defective (shorted-to-voltage)
Okay (rotor windings are open)
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 generator diode is being tested using a digital
multimeter set to the diode check position. A good
diode will read _____ if the leads are connected
one way across the diode and _____ if the leads
are reversed.
a)
b)
c)
d)
300/300
0.475/0.475
OL/OL
0.551/OL
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 generator diode is being tested using a digital
multimeter set to the diode check position. A good
diode will read _____ if the leads are connected
one way across the diode and _____ if the leads
are reversed.
a)
b)
c)
d)
300/300
0.475/0.475
OL/OL
0.551/OL
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. A generator (alternator) could test as producing
lower-than normal output, yet be okay, if _____.
a)
b)
c)
d)
The battery is weak or defective
The engine speed is not high enough during testing
The drive belt is loose or slipping
All of the above occur
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. A generator (alternator) could test as producing
lower-than normal output, yet be okay, if _____.
a)
b)
c)
d)
The battery is weak or defective
The engine speed is not high enough during testing
The drive belt is loose or slipping
All of the above occur
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