Ignition switch JEEP GRAND CHEROKEE 2002 WJ / 2.G Owner's Guide

REMOVAL
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Loosen the battery negative cable terminal
clamp pinch-bolt hex nut.
(3) Disconnect the battery negative cable terminal
clamp from the battery negative terminal post. If
necessary, use a battery terminal puller to remove
the terminal clamp from the battery post (Fig. 12).
(4) Loosen the battery positive cable terminal
clamp pinch-bolt hex nut.
(5) Disconnect the battery positive cable terminal
clamp from the battery positive terminal post. If nec-
essary, use a battery terminal puller to remove the
terminal clamp from the battery post.
(6) Remove the battery hold down from the bat-
tery. Refer toBattery Hold Downin this section of
the service manual for the procedure.
WARNING: WEAR A SUITABLE PAIR OF RUBBER
GLOVES (NOT THE HOUSEHOLD TYPE) WHEN
REMOVING A BATTERY BY HAND. SAFETY
GLASSES SHOULD ALSO BE WORN. IF THE BAT-
TERY IS CRACKED OR LEAKING, THE ELECTRO-
LYTE CAN BURN THE SKIN AND EYES.
(7) Remove the battery from the battery tray.
INSTALLATION
(1) Clean and inspect the battery. Refer to the pro-
cedures in this section.
(2) Position the battery onto the battery tray as a
unit. Ensure that the battery positive and negative
terminal posts are correctly positioned. The battery
cable terminal clamps must reach the correct battery
terminal post without stretching the cables (Fig. 13)
or (Fig. 14).
(3) Reinstall the battery hold downs onto the bat-
tery. Refer toBattery Hold DownsCAUTION: Be certain that the battery cable terminal
clamps are connected to the correct battery termi-
nal posts. Reverse battery polarity may damage
electrical components of the vehicle.
(4) Clean the battery cable terminal clamps and
the battery terminal posts.
Fig. 12 Remove Battery Cable Terminal Clamp -
Typical
1 - BATTERY
2 - BATTERY TERMINAL PULLER
Fig. 13 Battery Cables - 4.0L Engine
1 - BATTERY POSITIVE CABLE
2 - BATTERY NEGATIVE CABLE
3 - CLIPS
Fig. 14 Battery Cables - 4.7L Engine
1 - BATTERY POSITIVE CABLE
2 - BATTERY NEGATIVE CABLE
3 - CLIPS
WJBATTERY SYSTEM 8F - 15
BATTERY (Continued)

(5) Reconnect the battery positive cable terminal
clamp to the battery positive terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 6.8 N´m (60
in. lbs.).
(6) Reconnect the battery negative cable terminal
clamp to the battery negative terminal post. Tighten
the terminal clamp pinch-bolt hex nut to 6.8 N´m (
60 in. lbs.).
(7) Apply a thin coating of petroleum jelly or chas-
sis grease to the exposed surfaces of the battery cable
terminal clamps and the battery terminal posts.
BATTERY HOLDDOWN
DESCRIPTION
The battery hold down hardware consists of (Fig.
15) a molded plastic lip that is integral to the out-
board edge of the battery tray and support unit, a
molded plastic hold down bracket, a single hex screw
with a coned washer and a U-nut.
When installing a battery into the battery tray, be
certain that the hold down hardware is properly
installed and that the fasteners are tightened to the
proper specifications. Improper hold down fastener
tightness, whether too loose or too tight, can result in
damage to the battery, the vehicle or both.
OPERATION
The battery holddown secures the battery in the
battery tray. This holddown is designed to prevent
battery movement during the most extreme vehicle
operation conditions. Periodic removal and lubrica-
tion of the battery holddown hardware is recom-
mended to prevent hardware seizure at a later date.
CAUTION: Never operate a vehicle without a battery
holddown device properly installed. Damage to the
vehicle, components and battery could result.
REMOVAL
All of the battery hold down hardware can be ser-
viced without removal of the battery or the battery
tray and support unit.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Loosen the battery negative cable terminal
clamp pinch-bolt hex nut.
(3) Disconnect the battery negative cable terminal
clamp from the battery negative terminal post. If
necessary, use a battery terminal puller to remove
the terminal clamp from the battery post.
(4) Remove the screw with washer that secures the
battery hold down bracket to the U-nut on the
inboard side of the battery tray and support unit
(Fig. 16).
(5) Remove the battery hold down bracket from
the battery tray and support unit.
INSTALLATION
All of the battery hold down hardware can be ser-
viced without removal of the battery or the battery
tray and support unit.
(1) Clean and inspect the battery hold down hard-
ware. Refer to the procedures in this section of the
service manual.
(2) Be certain that the battery is properly posi-
tioned in the battery tray and support unit. The
ledge on the outboard side of the battery case must
be engaged under the lip on the outboard side of the
battery tray and support unit.
Fig. 15 Battery Hold Downs
1 - SCREW
2 - HOLD DOWN BRACKET
3 - BATTERY SUPPORT
4 - ACCUMULATOR
5 - NUT
6 - U-NUT
7 - STUD
8 - RADIATOR SUPPORT BRACKET
9 - U-NUT
10 - SCREW
11 - BATTERY TEMPERATURE SENSOR
12 - BATTERY
8F - 16 BATTERY SYSTEMWJ
BATTERY (Continued)

(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable terminal clamp (Fig. 19). Rotate and hold the
ignition switch in the Start position. Observe the
voltmeter. If voltage is detected, correct the poor con-
nection between the battery negative cable terminal
clamp and the battery negative terminal post.
(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
terminal clamp (Fig. 20). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor connection
between the battery positive cable terminal clamp
and the battery positive terminal post.
(3) Connect the voltmeter to measure between the
battery positive cable terminal clamp and the starter
solenoid B(+) terminal stud (Fig. 21). Rotate and hold
the ignition switch in the Start position. Observe the
voltmeter. If the reading is above 0.2 volt, clean and
tighten the battery positive cable eyelet terminal con-
nection at the starter solenoid B(+) terminal stud.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery positive cable.
(4) Connect the voltmeter to measure between the
battery negative cable terminal clamp and a good
clean ground on the engine block (Fig. 22). Rotate
and hold the ignition switch in the Start position.
Observe the voltmeter. If the reading is above 0.2
volt, clean and tighten the battery negative cable
eyelet terminal connection to the engine block.
Repeat the test. If the reading is still above 0.2 volt,
replace the faulty battery negative cable.
REMOVAL
Both the battery negative cable and the battery
positive cable are serviced in the battery wire har-
ness. If either battery cable is damaged or faulty, the
battery wire harness unit must be replaced.
(1) Turn the ignition switch to the Off position. Be
certain that all electrical accessories are turned off.
(2) Loosen the battery negative cable terminal
clamp pinch-bolt hex nut.
(3) Disconnect the battery negative cable terminal
clamp from the battery negative terminal post. If
necessary, use a battery terminal puller to remove
the terminal clamp from the battery post.
Fig. 19 TEST BATTERY NEGATIVE CONNECTION
RESISTANCE - TYPICAL
1 - VOLTMETER
2 - BATTERY
Fig. 20 TEST BATTERY POSITIVE CONNECTION
RESISTANCE - TYPICAL
1 - VOLTMETER
2 - BATTERY
Fig. 21 TEST BATTERY POSITIVE CABLE
RESISTANCE - TYPICAL
1 - BATTERY
2 - VOLTMETER
3 - STARTER MOTOR
WJBATTERY SYSTEM 8F - 19
BATTERY CABLE (Continued)

CHARGING
TABLE OF CONTENTS
page page
CHARGING
DESCRIPTION.........................24
OPERATION...........................24
DIAGNOSIS AND TESTING - CHARGING
SYSTEM............................24
SPECIFICATIONS
GENERATOR RATINGS - GAS POWERED . . 25
TORQUE - GAS POWERED.............25
SPECIAL TOOLS.......................26
BATTERY TEMPERATURE SENSOR
DESCRIPTION.........................26OPERATION...........................26
REMOVAL.............................26
INSTALLATION.........................26
GENERATOR
DESCRIPTION.........................27
OPERATION...........................27
REMOVAL.............................27
INSTALLATION.........................28
VOLTAGE REGULATOR
DESCRIPTION.........................28
OPERATION...........................28
CHARGING
DESCRIPTION
The charging system consists of:
²Generator
²Electronic Voltage Regulator (EVR) circuitry
within the Powertrain Control Module (PCM)
²Ignition switch
²Battery (refer to 8, Battery for information)
²Battery temperature sensor
²Generator Lamp (if equipped)
²Check Gauges Lamp (if equipped)
²Voltmeter (refer to 8, Instrument Cluster for
information)
²Wiring harness and connections (refer to 8, Wir-
ing for information)
OPERATION
The charging system is turned on and off with the
ignition switch. The system is on when the engine is
running and the ASD relay is energized. When the
ASD relay is on, voltage is supplied to the ASD relay
sense circuit at the PCM. This voltage is connected
through the PCM and supplied to one of the genera-
tor field terminals (Gen. Source +) at the back of the
generator.
The amount of DC current produced by the gener-
ator is controlled by the EVR (field control) circuitry
contained within the PCM. This circuitry is con-
nected in series with the second rotor field terminal
and ground.
A battery temperature sensor, located in the bat-
tery tray housing, is used to sense battery tempera-
ture. This temperature data, along with data from
monitored line voltage, is used by the PCM to vary
the battery charging rate. This is done by cycling theground path to control the strength of the rotor mag-
netic field. The PCM then compensates and regulates
generator current output accordingly.
All vehicles are equipped with On-Board Diagnos-
tics (OBD). All OBD-sensed systems, including EVR
(field control) circuitry, are monitored by the PCM.
Each monitored circuit is assigned a Diagnostic Trou-
ble Code (DTC). The PCM will store a DTC in elec-
tronic memory for certain failures it detects. Refer to
Diagnostic Trouble Codes in; Powertrain Control
Module; Electronic Control Modules for more DTC
information.
The Check Gauges Lamp (if equipped) monitors:
charging system voltage,engine coolant tempera-
ture and engine oil pressure. If an extreme condition
is indicated, the lamp will be illuminated. This is
done as reminder to check the three gauges. The sig-
nal to activate the lamp is sent via the CCD bus cir-
cuits. The lamp is located on the instrument panel.
Refer to 8, Instrument Cluster for additional infor-
mation.
DIAGNOSIS AND TESTING - CHARGING
SYSTEM
The following procedures may be used to diagnose
the charging system if:
²the check gauges lamp (if equipped) is illumi-
nated with the engine running
²the voltmeter (if equipped) does not register
properly
²an undercharged or overcharged battery condi-
tion occurs.
Remember that an undercharged battery is often
caused by:
²accessories being left on with the engine not
running
8F - 24 CHARGINGWJ

²a faulty or improperly adjusted switch that
allows a lamp to stay on. Refer to Ignition-Off Draw
Test in 8, Battery for more information.
INSPECTION
The Powertrain Control Module (PCM) monitors
critical input and output circuits of the charging sys-
tem, making sure they are operational. A Diagnostic
Trouble Code (DTC) is assigned to each input and
output circuit monitored by the On-Board Diagnostic
(OBD) system. Some charging system circuits are
checked continuously, and some are checked only
under certain conditions.
Refer to Diagnostic Trouble Codes in; Powertrain
Control Module; Electronic Control Modules for more
DTC information. This will include a complete list of
DTC's including DTC's for the charging system.
To perform a complete test of the charging system,
refer to the appropriate Powertrain Diagnostic Proce-
dures service manual and the DRBtscan tool. Per-
form the following inspections before attaching the
scan tool.(1) Inspect the battery condition. Refer to 8, Bat-
tery for procedures.
(2) Inspect condition of battery cable terminals,
battery posts, connections at engine block, starter
solenoid and relay. They should be clean and tight.
Repair as required.
(3) Inspect all fuses in both the fuseblock and
Power Distribution Center (PDC) for tightness in
receptacles. They should be properly installed and
tight. Repair or replace as required.
(4) Inspect generator mounting bolts for tightness.
Replace or tighten bolts if required. Refer to the Gen-
erator Removal/Installation section of this group for
torque specifications.
(5) Inspect generator drive belt condition and ten-
sion. Tighten or replace belt as required. Refer to
Belt Tension Specifications in 7, Cooling System.
(6) Inspect automatic belt tensioner (if equipped).
Refer to 7, Cooling System for information.
(7) Inspect generator electrical connections at gen-
erator field, battery output, and ground terminal (if
equipped). Also check generator ground wire connec-
tion at engine (if equipped). They should all be clean
and tight. Repair as required.
SPECIFICATIONS
GENERATOR RATINGS - GAS POWERED
TYPE PART NUMBER RATED SAE AMPS ENGINES MINIMUM TEST AMPS
BOSCH 56041322 136 4.0L 6-Cylinder 100
DENSO 56041324 136 4.7L V-8 100
TORQUE - GAS POWERED
DESCRIPTION N-m Ft. Lbs. In. Lbs.
Generator Mounting Bolts-4.0L 55 41
Generator Vertical Mounting Bolt-4.7L 40 29
Generator (long) Horizontal Mounting
Bolt-4.7L55 41
Generator (short) Horizontal Mounting
Bolt-4.7L55 41
Generator B+ Terminal Nut 11 95
WJCHARGING 8F - 25
CHARGING (Continued)

STARTING
TABLE OF CONTENTS
page page
STARTING
DESCRIPTION.........................29
OPERATION...........................30
DIAGNOSIS AND TESTING - STARTING
SYSTEM............................30
SPECIFICATIONS
TORQUE - STARTER...................35
STARTER MOTOR - GAS POWERED......35
STARTER MOTOR
DESCRIPTION.........................35
OPERATION...........................36DIAGNOSIS AND TESTING - STARTER
MOTOR .............................36
REMOVAL.............................37
INSTALLATION.........................38
STARTER MOTOR RELAY
DESCRIPTION.........................38
OPERATION...........................38
DIAGNOSIS AND TESTING - STARTER RELAY . 38
REMOVAL.............................39
INSTALLATION.........................40
STARTING
DESCRIPTION
An electrically operated engine starting system is
standard factory-installed equipment on this model.
The starting system is designed to provide the vehi-
cle operator with a convenient, efficient and reliable
means of cranking and starting the internal combus-
tion engine used to power the vehicle and all of its
accessory systems from within the safe and secure
confines of the passenger compartment. See the own-
er's manual in the vehicle glove box for more infor-
mation and instructions on the recommended use
and operation of the factory-installed starting sys-
tem.
The starting system consists of the following com-
ponents:
²Battery
²Starter relay
²Starter motor (including an integral starter sole-
noid)
²Ignition switch
²Park/neutral position switch
²Wire harnesses and connections (including the
battery cables).
This group provides complete service information
for the starter motor and the starter relay. Complete
service information for the other starting system
components can be located as follows:
²Refer toBatteryin the proper section of Group
8A - Battery for complete service information for the
battery.
²Refer toIgnition Switch and Key Lock Cyl-
inderin the proper section of Group 8D - Ignition
System for complete service information for the igni-
tion switch.²Refer toPark/Neutral Position Switchin the
proper section of Group 21 - Transmission for com-
plete service information for the park/neutral posi-
tion switch.
²Refer to the proper section ofGroup 8W - Wir-
ing Diagramsfor complete service information and
circuit diagrams for the starting system wiring com-
ponents.
Group 8A covers the Battery, Group 8B covers the
Starting Systems, and Group 8C covers the Charging
System. We have separated these systems to make it
easier to locate the information you are seeking
within this Service Manual. However, when attempt-
ing to diagnose any of these systems, it is important
that you keep their interdependency in mind.
The battery, starting, and charging systems in the
vehicle operate with one another, and must be tested
as a complete system. In order for the vehicle to start
and charge properly, all of the components that are
used in these systems must perform within specifica-
tions.
The diagnostic procedures used in each of these
groups include the most basic conventional diagnostic
methods, to the more sophisticated On-Board Diag-
nostics (OBD) built into the Powertrain Control Mod-
ule (PCM). Use of an induction-type milliampere
ammeter, volt/ohmmeter, battery charger, carbon pile
rheostat (load tester), and 12-volt test lamp may be
required.
All OBD-sensed systems are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. Refer to
On-Board Diagnostic Test For Charging System
in the Diagnosis and Testing section of Group 8C -
Charging System for more information.
WJSTARTING 8F - 29

OPERATION
The starting system components form two separate
circuits. A high-amperage feed circuit that feeds the
starter motor between 150 and 350 amperes, and a
low-amperage control circuit that operates on less
than 20 amperes. The high-amperage feed circuit
components include the battery, the battery cables,
the contact disc portion of the starter solenoid, and
the starter motor. The low-amperage control circuit
components include the ignition switch, the park/
neutral position switch, the starter relay, the electro-
magnetic windings of the starter solenoid, and the
connecting wire harness components.
Battery voltage is supplied through the low-amper-
age control circuit to the coil battery terminal of the
starter relay when the ignition switch is turned to
the momentary Start position. The park/neutral posi-
tion switch is installed in series between the starter
relay coil ground terminal and ground. This normally
open switch prevents the starter relay from being
energized and the starter motor from operating
unless the automatic transmission gear selector is in
the Neutral or Park positions.
When the starter relay coil is energized, the nor-
mally open relay contacts close. The relay contacts
connect the relay common feed terminal to the relay
normally open terminal. The closed relay contacts
energize the starter solenoid coil windings.
The energized solenoid pull-in coil pulls in the sole-
noid plunger. The solenoid plunger pulls the shift
lever in the starter motor. This engages the starter
overrunning clutch and pinion gear with the starter
ring gear on the automatic transmission torque con-
verter drive plate.
As the solenoid plunger reaches the end of its
travel, the solenoid contact disc completes the high-
amperage starter feed circuit and energizes the sole-
noid plunger hold-in coil. Current now flows between
the solenoid battery terminal and the starter motor,
energizing the starter.Once the engine starts, the overrunning clutch pro-
tects the starter motor from damage by allowing the
starter pinion gear to spin faster than the pinion
shaft. When the driver releases the ignition switch to
the On position, the starter relay coil is de-energized.
This causes the relay contacts to open. When the
relay contacts open, the starter solenoid plunger
hold-in coil is de-energized.
When the solenoid plunger hold-in coil is de-ener-
gized, the solenoid plunger return spring returns the
plunger to its relaxed position. This causes the con-
tact disc to open the starter feed circuit, and the shift
lever to disengage the overrunning clutch and pinion
gear from the starter ring gear.
DIAGNOSIS AND TESTING - STARTING
SYSTEM
The battery, starting, and charging systems oper-
ate with one another, and must be tested as a com-
plete system. In order for the vehicle to start and
charge properly, all of the components involved in
these systems must perform within specifications.
Group 8A covers the Battery, Group 8B covers the
Starting Systems, and Group 8C covers the Charging
System. We have separated these systems to make it
easier to locate the information you are seeking
within this Service Manual. However, when attempt-
ing to diagnose any of these systems, it is important
that you keep their interdependency in mind.
The diagnostic procedures used in these groups
include the most basic conventional diagnostic meth-
ods, to the more sophisticated On-Board Diagnostics
(OBD) built into the Powertrain Control Module
(PCM). Use of an induction-type milliampere amme-
ter, volt/ohmmeter, battery charger, carbon pile rheo-
stat (load tester), and 12-volt test lamp may be
required.
All OBD-sensed systems are monitored by the
PCM. Each monitored circuit is assigned a Diagnos-
tic Trouble Code (DTC). The PCM will store a DTC in
electronic memory for any failure it detects. Refer to
On-Board Diagnostic Test For Charging System
in the Diagnosis and Testing section of Group 8C -
Charging System for more information.
8F - 30 STARTINGWJ
STARTING (Continued)

Starting System Diagnosis
CONDITION POSSIBLE CAUSE CORRECTION
STARTER FAILS TO
OPERATE.1. Battery discharged or
faulty.1. Refer to Battery in the Diagnosis and Testing section of
Group 8A - Battery. Charge or replace the battery, if
required.
2. Starting circuit wiring
faulty.2. Refer to Starting System in Group 8W - Wiring
Diagrams. Test and repair the starter feed and/or control
circuits, if required.
3. Starter relay faulty. 3. Refer to Starter Relay in the Diagnosis and Testing
section of this group. Replace the starter relay, if
required.
4. Ignition switch faulty. 4. Refer to Ignition Switch and Key Lock Cylinder in the
Diagnosis and Testing section of Group 8D - Ignition
System. Replace the ignition switch, if required.
5. Park/Neutral position
switch faulty or
misadjusted.5. Refer to Park/Neutral Position Switch in the Diagnosis
and Testing section of Group 21 - Transmission. Replace
the park/neutral position switch, if required.
6. Starter solenoid faulty. 6. Refer to Starter Motor in the Diagnosis and Testing
section of this group. Replace the starter motor assembly,
if required.
7. Starter motor faulty. 7. If all other starting system components and circuits test
OK, replace the starter motor assembly.
STARTER ENGAGES,
FAILS TO TURN
ENGINE.1. Battery discharged or
faulty.1. Refer to Battery in the Diagnosis and Testing section of
Group 8A - Battery. Charge or replace the battery, if
required.
2. Starting circuit wiring
faulty.2. Refer to Starting System in Group 8W - Wiring
Diagrams. Test and repair the starter feed and/or control
circuits, if required.
3. Starter motor faulty. 3. If all other starting system components and circuits test
OK, replace the starter motor assembly.
4. Engine seized. 4. Refer to Engine Diagnosis in the Diagnosis and Testing
section of Group 9 - Engine.
STARTER ENGAGES,
SPINS OUT BEFORE
ENGINE STARTS.1. Starter ring gear faulty. 1. Refer to Starter Motor in the Removal and Installation
section of this group. Remove the starter motor to inspect
the starter ring gear. Replace the starter ring gear, if
required.
2. Starter motor faulty. 2. If all other starting system components and circuits test
OK, replace the starter motor assembly.
STARTER DOES NOT
DISENGAGE.1. Starter motor
improperly installed.1. Refer to Starter Motor in the Removal and Installation
section of this group. Tighten the starter mounting
hardware to the correct tightness specifications.
2. Starter relay faulty. 2. Refer to Starter Relay in the Diagnosis and Testing
section of this group. Replace the starter relay, if
required.
3. Ignition switch faulty. 3. Refer to Ignition Switch and Key Lock Cylinder in the
Diagnosis and Testing section of Group 8D - Ignition
System. Replace the ignition switch, if required.
4. Starter motor faulty. 4. If all other starting system components and circuits test
OK, replace the starter motor assembly.
WJSTARTING 8F - 31
STARTING (Continued)

INSPECTION
For complete circuit diagrams, refer toStarting
Systemin the Contents of Group 8W - Wiring Dia-
grams. Before removing any unit from the starting
system for repair or diagnosis, perform the following
inspections:
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, REFER TO GROUP 8M - PASSIVE
RESTRAINT SYSTEMS BEFORE ATTEMPTING ANY
STEERING WHEEL, STEERING COLUMN, OR
INSTRUMENT PANEL COMPONENT DIAGNOSIS OR
SERVICE. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
²Battery- Visually inspect the battery for indi-
cations of physical damage and loose or corroded
cable connections. Determine the state-of-charge and
cranking capacity of the battery. Charge or replace
the battery, if required. Refer toBatteryin the
proper section of Group 8A - Battery for complete ser-
vice information for the battery.
²Ignition Switch- Visually inspect the ignition
switch for indications of physical damage and loose
or corroded wire harness connections. Refer toIgni-
tion Switch and Key Lock Cylinderin the proper
section of Group 8D - Ignition System for complete
service information for the ignition switch.
²Park/Neutral Position Switch- Visually
inspect the park/neutral position switch for indica-
tions of physical damage and loose or corroded wire
harness connections. Refer toPark/Neutral Posi-
tion Switchin the proper section of Group 21 -
Transmission for complete service information for the
park/neutral position switch.
²Starter Relay- Visually inspect the starter
relay for indications of physical damage and loose or
corroded wire harness connections.
²Starter Motor- Visually inspect the starter
motor for indications of physical damage and loose or
corroded wire harness connections.
²Starter Solenoid- Visually inspect the starter
solenoid for indications of physical damage and loose
or corroded wire harness connections.
²Wiring- Visually inspect the wire harnesses for
damage. Repair or replace any faulty wiring, as
required. Refer to the proper section ofGroup 8W -
Wiring Diagramsfor complete service information
and circuit diagrams for the starting system wiring
components.TESTING
COLD CRANKING TEST
For complete circuit diagrams, refer toStarting
Systemin the Contents of Group 8W - Wiring Dia-
grams. The battery must be fully-charged and load-
tested before proceeding. Refer toBatteryin the
Diagnosis and Testing section of Group 8A - Battery
for the procedures.
(1) Connect a suitable volt-ampere tester to the
battery terminals (Fig. 1). See the instructions pro-
vided by the manufacturer of the volt-ampere tester
being used.
(2) Fully engage the parking brake.
(3) Place the automatic transmission gearshift
selector lever in the Park position.
(4) Verify that all lamps and accessories are
turned off.
(5) To prevent the engine from starting, remove
the Automatic ShutDown (ASD) relay. The ASD relay
is located in the Power Distribution Center (PDC), in
the engine compartment. Refer to the fuse and relay
layout label affixed to the underside of the PDC cover
for ASD relay identification and location.
(6) Rotate and hold the ignition switch in the Start
position. Note the cranking voltage and current
(amperage) draw readings shown on the volt-ampere
tester.
(a) If the voltage reads below 9.6 volts, refer to
Starter Motorin the Diagnosis and Testing sec-
tion of this group. If the starter motor is OK, refer
toEngine Diagnosisin the Diagnosis and Testing
section of Group 9 - Engine for further testing of
the engine. If the starter motor is not OK, replace
the faulty starter motor.
Fig. 1 Volts-Amps Tester Connections - Typical
1 - POSITIVE CLAMP
2 - NEGATIVE CLAMP
3 - INDUCTION AMMETER CLAMP
8F - 32 STARTINGWJ
STARTING (Continued)

(b) If the voltage reads above 9.6 volts and the
current (amperage) draw reads below specifica-
tions, refer toFeed Circuit Testin this section.
(c) If the voltage reads 12.5 volts or greater and
the starter motor does not turn, refer toControl
Circuit Testingin this section.
(d) If the voltage reads 12.5 volts or greater and
the starter motor turns very slowly, refer toFeed
Circuit Testin this section.
NOTE: A cold engine will increase the starter cur-
rent (amperage) draw reading, and reduce the bat-
tery voltage reading.
FEED CIRCUIT TEST
The starter feed circuit test (voltage drop method)
will determine if there is excessive resistance in the
high-amperage feed circuit. For complete circuit dia-
grams, refer toStarting Systemin the Contents of
Group 8W - Wiring Diagrams.
When performing these tests, it is important to
remember that the voltage drop is giving an indica-
tion of the resistance between the two points at
which the voltmeter probes are attached.
Example:When testing the resistance of the bat-
tery positive cable, touch the voltmeter leads to the
battery positive cable clamp and the cable connector
at the starter solenoid. If you probe the battery pos-
itive terminal post and the cable connector at the
starter solenoid, you are reading the combined volt-
age drop in the battery positive cable clamp-to-termi-
nal post connection and the battery positive cable.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing the
tests, be certain that the following procedures are
accomplished:
²Battery is fully-charged and load-tested. Refer to
Batteryin the Diagnosis and Testing section of
Group 8A - Battery for the procedures.
²Fully engage the parking brake.
²Place the automatic transmission gearshift selec-
tor lever in the Park position.
²
Verify that all lamps and accessories are turned off.
²To prevent the engine from starting, remove the
Automatic ShutDown (ASD) relay. The ASD relay is
located in the Power Distribution Center (PDC), in
the engine compartment. Refer to the fuse and relay
layout label affixed to the underside of the PDC cover
for ASD relay identification and location.
(1) Connect the positive lead of the voltmeter to
the battery negative terminal post. Connect the neg-
ative lead of the voltmeter to the battery negative
cable clamp (Fig. 2). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor contact between
the cable clamp and the terminal post.(2) Connect the positive lead of the voltmeter to
the battery positive terminal post. Connect the nega-
tive lead of the voltmeter to the battery positive cable
clamp (Fig. 3). Rotate and hold the ignition switch in
the Start position. Observe the voltmeter. If voltage
is detected, correct the poor contact between the
cable clamp and the terminal post.
(3) Connect the voltmeter to measure between the
battery positive terminal post and the starter sole-
noid battery terminal stud (Fig. 4). Rotate and hold
the ignition switch in the Start position. Observe the
voltmeter. If the reading is above 0.2 volt, clean and
tighten the battery cable connection at the solenoid.
Fig. 2 Test Battery Negative Connection Resistance
- Typical
1 - VOLTMETER
2 - BATTERY
Fig. 3 Test Battery Positive Connection Resistance -
Typical
1 - VOLTMETER
2 - BATTERY
WJSTARTING 8F - 33
STARTING (Continued)