
NOTE: A maximum of eight keys can be learned to
each SKIM. Once a key is learned to a SKIM, it (the
key) cannot be transferred to another vehicle.
(5) If ignition key programming is unsuccessful,
the DRBIIItscan tool will display one of the follow-
ing messages:
(a) Programming Not Attempted - The DRBIIIt
scan tool attempts to read the programmed key
status and there are no keys programmed into
SKIM memory.
(b) Programming Key Failed (Possible Used Key
From Wrong Vehicle) - SKIM is unable to program
key due to one of the following:
²Faulty ignition key transponder.
²Ignition key is programmed to another vehicle.
(c) 8 Keys Already Learned, Programming Not
Done - SKIM transponder ID memory is full.
(6) Obtain ignition keys to be programmed from
customer (8 keys maximum).
(7) Using the DRBIIItscan tool, erase all ignition
keys by selecting MISCELLANEOUS and ERASE
ALL CURRENT IGN. KEYS.
(8) Program all ignition keys.
Learned Key In Ignition - Ignition key transponder
ID is currently programmed in SKIM memory.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the steering column upper and lower
shrouds. Refer to Steering, Column, Shroud,
Removal.
(3) Disconnect the steering column wire harness
connector from the Sentry Key Immobilizer Module
(SKIM)
(4) Remove the screw securing the SKIM module
to the steering column (Fig. 8).
(5) Release the SKIM antenna ring retaining clips
from around the ignition switch lock cylinder housing
and remove the SKIM.
INSTALLATION
NOTE: If the SKIM is replaced with a new unit, a
DRBIIITscan tool MUST be used to initialize the
new SKIM and to program at least two Sentry Key
transponders. (Refer to 8 - ELECTRICAL/VEHICLE
THEFT SECURITY - STANDARD PROCEDURE).
(1) Slide the SKIM antenna ring around the igni-
tion switch lock cylinder housing and clip in place
(Fig. 8).
(2) Install the retaining screw.
(3) Connect the steering column wire harness con-
nector to the Sentry Key Immobilizer Module
(SKIM).(4) Install the steering column upper and lower
shrouds. Refer to Steering, Column, Shroud, Installa-
tion.
(5) Connect the battery negative cable.
TRANSFER CASE CONTROL
MODULE
DESCRIPTION
The Transfer Case Control Module (TCCM) (Fig. 9)
is a microprocessor-based assembly, controlling the
4X4 transfer case shift functions via the actuation of
a shift motor and utilizing the feedback of a mode
sensor assembly. Communication is via the PCI serial
bus. Inputs include user selectable 4X4 modes that
include 2WD, 4HI, 4LO, and Neutral. The logic and
driver circuitry is contained in a molded plastic hous-
ing with an embedded heat-sink and is located
behind the left side of the lower instrument panel.
OPERATION
The Transfer Case Control Module (TCCM) utilizes
the input from the transfer case mounted mode sen-
sor, the instrument panel mounted selector switch,
and the following information from the vehicle's PCI
serial bus to determine if a shift is allowed.
²Engine RPM and Vehicle Speed
Fig. 8 SENTRY KEY IMMOBILIZER MODULE (SKIM)
1 - SENTRY KEY IMMOBILIZER MODULE (SKIM)
2 - STEERING COLUMN
3 - SCREW
4 - WIRING HARNES
DRELECTRONIC CONTROL MODULES 8E - 15
SENTRY KEY IMMOBILIZER MODULE (Continued)

ments for shifting are not met, illuminate the 4H
LED and flash the destination LED as an indication
to the driver that all of the driver controllable shift
conditions are not being met). If this requires
another range or mode shift, begin the range/mode
shift process.
²If the desired mode sensor code is not received
after the shift timer expires (i.e. a blocked or other
condition exists), refer to the section on Blocked Shift
Strategy.
BLOCKED SHIFT STRATEGY
When a shift is commanded, the shift motor will be
driven towards its destination position, except in the
case of shifting out of Neutral if 4L was selected (the
transfer case will shift to the 4H position first, before
proceeding to 4L). If the shift is blocked on the way
to the destination, the TCCM may attempt to drive
the motor back to the original position. This process
will be allowed to occur 5 times. If the transfer case
has reached a non-NEUTRAL 'D' channel during the
shift re-attempts, the LED for the achieved gear posi-
tion is illuminated and the shift attempts are
stopped. To re-attempt the desired shift, the selector
switch will need to be rotated to the current position
until the switch debounce timer expires then a shift
will need to be requested again.
At the end of the 5th blocked attempt, the shift
motor is driven towards the last known 'D' channel
position. If this motor drive allows the transfer case
to reach the 2WD/AWD 'D' channel, or the 2WD/AWD
between gear position on the 4H side of 2WD/AWD,
the shift is considered complete and the shift
attempts are ended.
If the mode sensor is in the NEUTRAL region at
the expiration of the shift timer, the TCCM will con-
tinue to make the shift attempts according to the
blocked shift strategy independent of whether or not
the driver controlled conditions are met.
For shifts from NEUTRAL, if all 5 attempts fail to
reach the desired position (which by default is 4H),
the motor will be driven to stall in the direction of
4H or 4L, depending on the achieved position. If the
transfer case has reached the 2WD/AWD or 4L
between gear position nearest the NEUTRAL posi-
tions and the shift conditions are no longer being
met, the transfer case will be driven toward the cor-
responding 'D' channel. Otherwise, the transfer case
will be driven in the direction opposite the last
attempt with the desired target being 4H or 4L.
If the transfer case reaches the 2WD/AWD 'D'
channel when being driven in the 4H direction, then
one final 1.0 second drive toward 4H is attempted. If
the transfer case then reaches any of the 4H posi-
tions, the shift is considered complete and the 4H
LED is illuminated. If the transfer case is still the2WD/AWD position, the shift is considered complete
and the 2WD/AWD LED is illuminated.
NOTE: If after the 5th blocked shift and reversal
attempt, if the transfer case position is in the NEU-
TRAL region, shift attempts will continue until a
non-NEUTRAL 'D' channel is reached.
SHIFT REVERSAL TARGETS
If the shift timer expires (1 second per 'D' channel)
and the transfer case has not reached the desired
position, all shifts will attempt to return to their
original position with the exceptions of:
²If the intended shift is going to the High rail
from Low and can't make it, but it can make the
2WD/AWD position, the motor stops at that position.
The TCCM will not attempt to cross back over NEU-
TRAL if it does not have to. This means that there
was a block on the first attempt to go to 4H and the
transfer case has made it through NEUTRAL to a
known good position, then the motor will go back
only to the 2WD/4WD position and execute the
remainder of the attempts from there.
²For shifts out of NEUTRAL, any time a shift is
commanded out of NEUTRAL, the system needs to
get out. The TCCM should never go to NEUTRAL
unless the driver is commanding it and all required
conditions are being met
ENCODER DRIFT CORRECTION
Whenever a shift is completed, the TCCM stores
the position in memory as the transfer case's
intended position. The TCCM continuously monitors
the mode sensor and if the mode sensor drifts toward
into a NEUTRAL region sensor position for 2.0 sec-
onds, the TCCM will perform a motor drive to correct
the drift. The transfer case will be driven toward the
intended position for 1.0 seconds 100 msec. The
TCCM will wait for 2.0 seconds 50 msec. and repeat
the attempt to shift to the desired position. This will
continue until the intended position is reached.
SHIFT MOTOR BRAKING
Two modes of shift motor braking are employed to
improve shift performance, static and dynamic. Static
shift motor braking is utilized under the following
conditions:
²Whenever the transfer case is in the 2WD/AWD
or 4L 'D' channel position.
²Whenever an invalid mode sensor code is
present.
Static motor braking is achieved by applying +12V
on both shift motor wires.
NOTE: Static Shift Motor Braking is independent of
ignition key position.
8E - 18 ELECTRONIC CONTROL MODULESDR
TRANSFER CASE CONTROL MODULE (Continued)

SHIFT ATTEMPT LIMIT
To protect the transfer case system, the TCCM will
impose a limit on the number of shifts that can occur
over a calibrated time period. The system will monitor
the number of 'D' channel segment transitions that
occur in any 30 second time period. If the number of
segment transitions is 30 or greater, the system will go
into a default mode. The default mode of operation for
shifting is that the number of allowed 'D' channel tran-
sitions permitted to occur will be 3 over each 15 second
100 msec calibrated window of time. After 5 minutes
100 msec, the motor can be assumed to have cooled
down and the system will revert to normal operation.
The following rules also apply to the shift limit:
²The attempt limit will not prevent shifts coming
out of NEUTRAL, they will be allowed regardless of
the counter/timer.
²Any shift that is in progress when the counter
reaches a maximum count in time will be allowed to
complete before the default mode is entered. D-chan-
nel transitions during this period will not be counted
towards the default mode limit.
²A block, regardless of the direction, whether
towards destination or back towards reversal target
(shift timer expiring), will count as a value of 2 tran-
sitions towards the 30 segment transitions to go into
default mode as defined above. Current attempt limit
values are 30 transitions in 30 seconds and default
mode values are 3 transitions every 15 seconds for 5
minutes.
TRANSMISSION CONTROL
MODULE
DESCRIPTION
The Transmission Control Module (TCM) (Fig. 10)
may be sub-module within the Powertrain Control
Module (PCM) or a standalone module, depending on
the vehicle engine. The PCM, and TCM when
equipped, is located at the right rear of the engine
compartment, near the right inner fender.
OPERATION
The Transmission Control Module (TCM) controls
all electronic operations of the transmission. The
TCM receives information regarding vehicle opera-
tion from both direct and indirect inputs, and selects
the operational mode of the transmission. Direct
inputs are hardwired to, and used specifically by the
TCM. Indirect inputs are shared with the TCM via
the vehicle communication bus.
Some examples ofdirect inputsto the TCM are:
²Battery (B+) voltage
²Ignition ªONº voltage
²Transmission Control Relay (Switched B+)²Throttle Position Sensor
²Crankshaft Position Sensor
²Transmission Range Sensor
²Pressure Switches
²Transmission Temperature Sensor
²Input Shaft Speed Sensor
²Output Shaft Speed Sensor
²Line Pressure Sensor
Some examples ofindirect inputsto the TCM are:
²Engine/Body Identification
²Manifold Pressure
²Target Idle
²Torque Reduction Confirmation
²Engine Coolant Temperature
²Ambient/Battery Temperature
²DRBIIItScan Tool Communication
Based on the information received from these var-
ious inputs, the TCM determines the appropriate
shift schedule and shift points, depending on the
present operating conditions and driver demand.
This is possible through the control of various direct
and indirect outputs.
Some examples of TCMdirect outputsare:
²Transmission Control Relay
²Solenoids
²Torque Reduction Request
Some examples of TCMindirect outputsare:
²Transmission Temperature (to PCM)
²PRNDL Position (to BCM)
In addition to monitoring inputs and controlling
outputs, the TCM has other important responsibili-
ties and functions:
²Storing and maintaining Clutch Volume Indexes
(CVI)
²
Storing and selecting appropriate Shift Schedules
²System self-diagnostics
²Diagnostic capabilities (with DRBIIItscan tool)
Fig. 10 PCM/TCM Location
1 - RIGHT FENDER
2 - TRANSMISSION CONTROL MODULE
3 - POWERTRAIN CONTROL MODULE
DRELECTRONIC CONTROL MODULES 8E - 19
TRANSFER CASE CONTROL MODULE (Continued)

ELECTRONIC MODULE IGNITION-OFF DRAW (IOD) TABLE
ModuleTime Out?
(If Yes, Interval And Wake-Up Input)IODIOD After Time
Out
ElectroMechanical
Instrument Cluster
(EMIC)No 0.44 milliampere N/A
Combination Flasher No 0.08 milliampere N/A
(2) Determine that the underhood lamp is operat-
ing properly, then disconnect the lamp wire harness
connector or remove the lamp bulb.
(3) Disconnect the battery negative cable.
(4) Set an electronic digital multi-meter to its
highest amperage scale. Connect the multi-meter
between the disconnected battery negative cable ter-
minal clamp and the battery negative terminal post.
Make sure that the doors remain closed so that the
illuminated entry system is not activated. The multi-
meter amperage reading may remain high for up to
three minutes, or may not give any reading at all
while set in the highest amperage scale, depending
upon the electrical equipment in the vehicle. The
multi-meter leads must be securely clamped to the
battery negative cable terminal clamp and the bat-
tery negative terminal post. If continuity between the
battery negative terminal post and the negative cable
terminal clamp is lost during any part of the IOD
test, the electronic timer function will be activated
and all of the tests will have to be repeated.
(5) After about three minutes, the high-amperage
IOD reading on the multi-meter should become very
low or nonexistent, depending upon the electrical
equipment in the vehicle. If the amperage reading
remains high, remove and replace each fuse or circuit
breaker in the Integrated Power Module (IPM), one
at a time until the amperage reading becomes very
low, or nonexistent. Refer to the appropriate wiring
information in this service manual for complete Inte-
grated Power Module fuse, circuit breaker, and cir-
cuit identification. This will isolate each circuit and
identify the circuit that is the source of the high-am-
perage IOD. If the amperage reading remains high
after removing and replacing each fuse and circuit
breaker, disconnect the wire harness from the gener-
ator. If the amperage reading now becomes very low
or nonexistent, refer to Charging System for the
proper charging system diagnosis and testing proce-
dures. After the high-amperage IOD has been cor-
rected, switch the multi-meter to progressively lower
amperage scales and, if necessary, repeat the fuse
and circuit breaker remove-and-replace process to
identify and correct all sources of excessive IOD. It is
now safe to select the lowest milliampere scale of the
multi-meter to check the low-amperage IOD.CAUTION: Do not open any doors, or turn on any
electrical accessories with the lowest milliampere
scale selected, or the multi-meter may be damaged.
(6) Observe the multi-meter reading. The low-am-
perage IOD should not exceed thirty-five milliam-
peres (0.035 ampere). If the current draw exceeds
thirty-five milliamperes, isolate each circuit using the
fuse and circuit breaker remove-and-replace process
in Step 5. The multi-meter reading will drop to
within the acceptable limit when the source of the
excessive current draw is disconnected. Repair this
circuit as required; whether a wiring short, incorrect
switch adjustment, or a component failure is at fault.
STANDARD PROCEDURE - USING MICRO 420
BATTERY TESTER
Always use the Micro 420 Instruction Manual that
was supplied with the tester as a reference. If the
Instruction Manual is not available the following pro-
cedure can be used:
Fig. 9 MICRO 420 BATTERY TESTER
8F - 12 BATTERY SYSTEMDR
BATTERY (Continued)

WARNING: ALWAYS WEAR APPROPRIATE EYE
PROTECTION AND USE EXTREME CAUTION WHEN
WORKING WITH BATTERIES.
BATTERY TESTING
(1) If testing the battery OUT-OF-VEHICLE, clean
the battery terminals with a wire brush before test-
ing. If the battery is equipped with side post termi-
nals, install and tighten the supplied lead terminal
stud adapters. Do not use steel bolts. Failure to prop-
erly install the stud adapters, or using stud adapters
that are dirty or worn-out may result in false test
readings.
(2) If testing the battery IN-THE-VEHICLE, make
certain all of the vehicle accessory loads are OFF,
including the ignition.The preferred test position
is at the battery terminal. If the battery is not
accessible, you may test using both the positive and
negative jumper posts. Select TESTING AT JUMPER
POST when connecting to that location.
(3) Connect the tester (Fig. 9) to the battery or
jumper posts, the red clamp to positive (+) and the
black clamp to negative (±).
NOTE: Multiple batteries connected in parallel must
have the ground cable disconnected to perform a
battery test. Failure to disconnect may result in
false battery test readings.
(4) Using the ARROW key selectinoroutof vehi-
cle testing and press ENTER to make a selection.
(5) If not selected, choose the Cold Cranking Amp
(CCA) battery rating. Or select the appropriate bat-
tery rating for your area (see menu). The tester will
then run its self programmed test of the battery and
display the results. Refer to the test result table
noted below.
CAUTION: If REPLACE BATTERY is the result of the
test, this may mean a poor connection between the
vehicle's cables and battery exists. After discon-
necting the vehicle's battery cables from the bat-
tery, retest the battery using the OUT-OF-VEHICLE
test before replacing.
(6) While viewing the battery test result, press the
CODE button and the tester will prompt you for the
last 4 digits of the VIN. Use the UP/DOWN arrow
buttons to scroll to the correct character; then press
ENTER to select and move to the next digit. Then
press the ENTER button to view the SERVICE
CODE. Pressing the CODE button a second time will
return you to the test results.
BATTERY TEST RESULTS
GOOD BATTERY Return to service
GOOD - RECHARGE Fully charge battery and
return to service
CHARGE & RETEST Fully charge battery and
retest battery
REPLACE BATTERY Replace the battery and
retest complete system
BAD-CELL REPLACE Replace the battery and
retest complete system
NOTE: The SERVICE CODE is required on every
warranty claim submitted for battery replacement.
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. 10).
(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 (Fig. 10).
(6) Remove the battery hold down retaining bolt.
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.
Fig. 10 Removing Battery Cable Terminal Clamp
1 - BATTERY
2 - BATTERY TERMINAL PULLER
DRBATTERY SYSTEM 8F - 13
BATTERY (Continued)

also provide a return path for electrical current gen-
erated by the charging system for restoring the volt-
age potential of the battery. The female battery
terminal clamps on the ends of the battery cable
wires provide a strong and reliable connection of the
battery cable to the battery terminal posts. The ter-
minal pinch bolts allow the female terminal clamps
to be tightened around the male terminal posts on
the top of the battery. The eyelet terminals secured
to the ends of the battery cable wires opposite the
female battery terminal clamps provide secure and
reliable connection of the battery to the vehicle elec-
trical system.
DIAGNOSIS AND TESTING - BATTERY CABLES
A voltage drop test will determine if there is exces-
sive resistance in the battery cable terminal connec-
tions or the battery cables. If excessive resistance is
found in the battery cable connections, the connec-
tion point should be disassembled, cleaned of all cor-
rosion or foreign material, then reassembled.
Following reassembly, check the voltage drop for the
battery cable connection and the battery cable again
to confirm repair.
When performing the voltage drop test, it is impor-
tant to remember that the voltage drop is giving an
indication of the resistance between the two points at
which the voltmeter probes are attached.EXAM-
PLE:When testing the resistance of the battery pos-
itive cable, touch the voltmeter leads to the battery
positive cable terminal clamp and to the battery pos-
itive cable eyelet terminal at the starter solenoid
B(+) terminal stud. If you probe the battery positive
terminal post and the battery positive cable eyelet
terminal at the starter solenoid B(+) terminal stud,
you are reading the combined voltage drop in the
battery positive cable terminal clamp-to-terminal
post connection and the battery positive cable.
VOLTAGE DROP TEST
WARNING: MODELS EQUIPPED WITH A DIESEL
ENGINE HAVE AN AUTOMATIC SHUTDOWN (ASD)
RELAY LOCATED IN THE POWER DISTRIBUTION
CENTER (PDC). REMOVAL OF THE ASD RELAY
MAY NOT PREVENT THE DIESEL ENGINE FROM
STARTING. BE CERTAIN TO DISCONNECT THE
FUEL SHUTDOWN SOLENOID WIRE HARNESS
CONNECTOR TO PREVENT THE ENGINE FROM
STARTING. FAILURE TO DO SO MAY RESULT IN
PERSONAL INJURY.
The following operation will require a voltmeter
accurate to 1/10 (0.10) volt. Before performing this
test, be certain that the following procedures are
accomplished:²The battery is fully-charged and tested (Refer to
8 - ELECTRICAL/BATTERY SYSTEM/BATTERY -
STANDARD PROCEDURE).
²Fully engage the parking brake.
²If the vehicle is equipped with an automatic
transmission, place the gearshift selector lever in the
Park position. If the vehicle is equipped with a man-
ual transmission, place the gearshift selector lever in
the Neutral position and block the clutch pedal in the
fully depressed position.
²Verify that all lamps and accessories are turned
off.
²To prevent a gasoline engine from starting,
remove the Automatic ShutDown (ASD) relay. The
ASD relay is located in the Integrated Power Module
(IPM), in the engine compartment. See the fuse and
relay layout label on the underside of the IPM 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 terminal clamp (Fig. 11). 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.
NOTE: If the vehicle is equipped with two 12v bat-
teries, step #1 must be performed twice, once for
each battery.
(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. 12). Rotate and hold the ignition
switch in the Start position. Observe the voltmeter. If
voltage is detected, correct the poor connection
Fig. 11 Test Battery Negative Connection
Resistance - Typical
1 - VOLTMETER
2 - BATTERY
DRBATTERY SYSTEM 8F - 15
BATTERY CABLES (Continued)

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 PCM (Powertrain Control Module), or ECM
(Diesel) monitors critical input and output circuits of
the charging system, making sure they are opera-
tional. 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
TYPE PART NUMBER RATED SAE AMPS ENGINES
DENSO 56029700AA 136 3.7L / 4.7L
DENSO 56029701AA 136 5.9L Gas
BOSCH 56041120AC 136 3.7L / 4.7L
BOSCH 56028238AB 136 5.9L Gas
DENSO 56028560AA 136 8.0L
DENSO 56028696AA 136 5.7L Gas/5.9L Diesel
BOSCH 56028699AA 136 5.7L Gas/5.9L Diesel
SPECIFICATIONS - TORQUE - GENERATOR /
CHARGING SYSTEM
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Generator Mounting Bolts - 5.7L 41 30 -
Generator Support Bracket
Bolt/Nuts - 5.7L41 30 -
Generator Mounting Bolts - 8.0L 41 30 -
Generator Upper Mounting Bolt -
5.9L Diesel Engine41 30 -
Generator Upper Mounting Bolt -
5.9L Gas Engine41 30 -
8F - 20 CHARGINGDR
CHARGING (Continued)

STARTING
TABLE OF CONTENTS
page page
STARTING
DESCRIPTION.........................28
OPERATION...........................28
DIAGNOSIS AND TESTING - STARTING
SYSTEM............................29
SPECIFICATIONS
STARTING SYSTEM...................33
SPECIFICATIONS - TORQUE - STARTING
SYSTEM............................34
STARTER MOTOR
DIAGNOSIS AND TESTING - STARTER
MOTOR .............................34REMOVAL.............................34
INSTALLATION.........................37
STARTER MOTOR RELAY
DESCRIPTION.........................38
OPERATION...........................38
DIAGNOSIS AND TESTING - STARTER RELAY . 38
REMOVAL.............................39
INSTALLATION.........................39
STARTING
DESCRIPTION
The starting system consists of:
²Starter relay
²Starter motor (including an integral starter sole-
noid)
Other components to be considered as part of start-
ing system are:
²Battery
²Battery cables
²Ignition switch and key lock cylinder
²Clutch pedal position switch (manual transmis-
sion)
²Park/neutral position switch (automatic trans-
mission)
²Wire harnesses and connections.
The Battery, Starting, and Charging systems oper-
ate in conjunction with one another, and must be
tested as a complete system. For correct operation of
starting/charging systems, all components used in
these 3 systems must perform within specifications.
When attempting to diagnose any of these systems, it
is important that you keep their interdependency in
mind.
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.
Certain starting system components are monitored
by the PCM and may produce a Diagnostic TroubleCode (DTC). Refer to Diagnostic Trouble Codes in
Emission Control for a list of codes.OPERATION
The starting system components form two separate
circuits. A high-amperage feed circuit that feeds the
starter motor between 150 and 350 amperes (700
amperes - diesel engine), 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 igni-
tion switch, the clutch pedal position switch (manual
transmission), the park/neutral position switch (auto-
matic transmission), the starter relay, the electro-
magnetic windings of the starter solenoid, and the
connecting wire harness components.
If the vehicle is equipped with a manual transmis-
sion, it has a clutch pedal position switch installed in
series between the ignition switch and the coil bat-
tery terminal of the starter relay. This normally open
switch prevents the starter relay from being ener-
gized when the ignition switch is turned to the Start
position, unless the clutch pedal is depressed. This
feature prevents starter motor operation while the
clutch disc and the flywheel are engaged. The starter
relay coil ground terminal is always grounded on
vehicles with a manual transmission.
If the vehicle is equipped with an automatic trans-
mission, battery voltage is supplied through the low-
amperage control circuit to the coil battery terminal
of the starter relay when the ignition switch is
turned to the Start position. The park/neutral posi-
tion switch is installed in series between the starter
relay coil ground terminal and ground. This normally
8F - 28 STARTINGDR