Wiring harness JEEP GRAND CHEROKEE 2002 WJ / 2.G User Guide

Page 296 of 2199

problem being diagnosed is related to one of the
symptoms listed below, be certain to check the
remote radio switches and circuits. (Refer to 8 -
ELECTRICAL/AUDIO/REMOTE SWITCHES -
OPERATION).
²Stations changing with no remote radio switch
input
²Radio memory presets not working properly
²Volume changes with no remote radio switch
input
²Remote radio switch buttons taking on other
functions
²CD player skipping tracks
²Mode (AM, FM, CD, CD changer) changes with
no remote radio switch input
²Remote radio switch inoperative.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CAUTION: The speaker output of the radio receiver
is a ªfloating groundº system. Do not allow any
speaker lead to short to ground, as damage to the
radio receiver may result.
(1) Check the fused B(+) fuse in the junction block.
If OK, go to Step 2. If not OK, repair the shorted cir-
cuit or component as required and replace the faulty
fuse.
(2) Check for battery voltage at the fused B(+) fuse
in the junction block. If OK, go to Step 3. If not OK,
repair the open fused B(+) circuit to the Power Dis-
tribution Center (PDC) fuse as required.
(3) Check the fused ignition switch output (acc/
run) fuse in the junction block. If OK, go to Step 4. If
not OK, repair the shorted circuit or component as
required and replace the faulty fuse(s).(4) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (acc/run) fuse in the junction block. If OK, go
to Step 5. If not OK, repair the open fused ignition
switch output (acc/run) circuit to the ignition switch
as required.
(5) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Remove the radio receiver from the instrument
panel, but do not disconnect the wire harness connec-
tors. Check for continuity between the radio receiver
chassis and a good ground. There should be continu-
ity. If OK, go to Step 6. If not OK, repair the open
ground circuit to ground as required.
(6) Test the radio receiver antenna. (Refer to 8 -
ELECTRICAL/AUDIO/ANTENNA BODY & CABLE -
DIAGNOSIS AND TESTING). If OK, go to Step 7. If
not OK, replace the faulty antenna or coaxial cable
as required.
(7) Connect the battery negative cable. Turn the
ignition switch to the On position. Check for battery
voltage at the fused ignition switch output (acc/run)
circuit cavity of the 22 pin radio wire harness connec-
tor. If OK, go to Step 8. If not OK, repair the open
fused ignition switch output (acc/run) circuit to the
junction block fuse as required.
(8) Turn the ignition switch to the Off position.
Check for battery voltage at the fused B(+) circuit
cavity of the 22 pin radio wire harness connector. If
OK, replace the faulty radio receiver. If not OK,
repair the open fused B(+) circuit to the junction
block fuse as required.
REMOVAL
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the center upper bezel from the instru-
ment panel.(Refer to 23 - BODY/INSTRUMENT
PANEL - REMOVAL).
(3) Remove the four screws that secure the radio
receiver to the instrument panel (Fig. 12).
WJAUDIO 8A - 17
RADIO (Continued)

Page 299 of 2199

The two remote radio switch units share a common
steering wheel wire harness with the vehicle speed
control switches. The steering wheel wire harness is
connected to the instrument panel wire harness
through the clockspring. (Refer to 8 - ELECTRICAL/
RESTRAINTS/CLOCKSPRING - DESCRIPTION) for
more information on this component.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
OPERATION
The six switches in the two remote radio switch
units are normally open, resistor multiplexed
momentary switches that are hard wired to the Body
Control Module (BCM) through the clockspring. The
BCM sends a five volt reference signal to both switch
units on one circuit, and senses the status of all of
the switches by reading the voltage drop on a second
circuit.
When the BCM senses an input (voltage drop) from
any one of the remote radio switches, it sends the
proper switch status messages on the ProgrammableCommunication Interface (PCI) data bus network to
the radio receiver. The electronic circuitry within the
radio receiver is programmed to respond to these
remote radio switch status messages by adjusting the
radio settings as requested. For diagnosis of the
BCM or the PCI data bus, the use of a DRB scan tool
and the proper Diagnostic Procedures manual are
recommended.
For more information on the features and control
functions for each of the remote radio switches, see
the owner's manual in the vehicle glove box.
DIAGNOSIS AND TESTING - REMOTE
SWITCHES
Any diagnosis of the Audio system should
begin with the use of the DRB IIItdiagnostic
tool. For information on the use of the DRB
IIIt, refer to the appropriate Diagnostic Service
Manual.
For complete circuit diagrams, refer to the appro-
priate wiring information. The wiring information
includes wiring diagrams, proper wire and connector
repair procedures, details of wire harness routing
and retention, connector pin-out information and
location views for the various wire harness connec-
tors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
(1) Disconnect and isolate the battery negative
cable. Remove the remote radio switch(es) (Fig. 16)
from the steering wheel.
(2) Use an ohmmeter to check the switch resis-
tances as shown in the Remote Radio Switch Test
chart. If the remote radio switch resistances check
OK, go to Step 3. If not OK, replace the faulty
switch.
Fig. 15 Remote Radio Switches
1 - PRESET ADVANCE
2 - SEEK
3 - MODE ADVANCE
4 - VOLUME
8A - 20 AUDIOWJ
REMOTE SWITCHES (Continued)

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(2) Press firmly and evenly on the remote radio
switch until each of the switch snap features is fully
engaged in the mounting hole of the steering wheel
rear trim cover.
(3) Reconnect the steering wheel wire harness con-
nector to the connector receptacle of the remote radio
switch.
(4) Install the speed control switch onto the steer-
ing wheel. Refer to Electrical, Speed Control for the
procedures.
(5) Install the driver side airbag onto the steering
wheel. (Refer to 8 - ELECTRICAL/RESTRAINTS/
DRIVER AIRBAG - INSTALLATION) for the proce-
dures.
(6) Reconnect the battery negative cable.
SPEAKER
DESCRIPTION
STANDARD
The standard equipment speaker system includes
speakers in six locations. One 6.4 centimeter (2.50
inch) diameter tweeter is installed on each end of the
instrument panel top pad. One 15.2 by 22.9 centime-
ter (6 by 9 inch) full-range speaker is located in each
front door. There is also one full-range 16.5 centime-
ter (6.5 inch) diameter full-range speaker located in
each rear door.
PREMIUM
The optional premium speaker system features six
Infinity model speakers in six locations. Each of the
standard speakers is replaced with Infinity model
speakers. One 6.4 centimeter (2.50 inch) diameter
Infinity tweeter is installed on each end of the
instrument panel top pad. One 15.2 by 22.9 centime-
ter (6 by 9 inch) Infinity woofer is located in each
front door. There is also one full-range 16.5 centime-
ter (6.5 inch) diameter Infinity full-range speaker
located in each rear door. The premium speaker sys-
tem also includes an additional Infinity power ampli-
fier. The total available power of the premium
speaker system is about 180 watts.
OPERATION
STANDARD
Each of the two tweeters and four full-range speak-
ers used in the standard speaker system is driven by
the amplifier that is integral to the factory-installed
radio receiver. For complete circuit diagrams, refer to
the appropriate wiring information. The wiring infor-
mation includes wiring diagrams, proper wire and
connector repair procedures, details of wire harness
routing and retention, connector pin-out information
and location views for the various wire harness con-
nectors, splices and grounds.
PREMIUM
The six Infinity speakers used in the premium
speaker system are all driven by the radio receiver
through an Infinity power amplifier. For complete cir-
cuit diagrams, refer to the appropriate wiring infor-
mation. The wiring information includes wiring
diagrams, proper wire and connector repair proce-
dures, details of wire harness routing and retention,
connector pin-out information and location views for
the various wire harness connectors, splices and
grounds.
Fig. 17 Remote Radio Switches Remove/Install
1 - STEERING WHEEL
2 - SPEED CONTROL SWITCH
3 - SCREW
4 - DRIVER SIDE AIRBAG MODULE
5 - REMOTE RADIO SWITCH
6 - REAR TRIM COVER
8A - 22 AUDIOWJ
REMOTE SWITCHES (Continued)

Page 302 of 2199

DIAGNOSIS AND TESTING - SPEAKER
Any diagnosis of the Audio system should
begin with the use of the DRB IIItdiagnostic
tool. For information on the use of the DRB
IIIt, refer to the appropriate Diagnostic Service
Manual.
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
WARNING: DISABLE THE AIRBAG SYSTEM
BEFORE ATTEMPTING ANY STEERING WHEEL,
STEERING COLUMN, SEAT BELT TENSIONER, SIDE
AIRBAG, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CAUTION: The speaker output of the radio is a
ªfloating groundº system. Do not allow any speaker
lead to short to ground, as damage to the radio
may result.
(1) Turn the ignition switch to the On position.
Turn the radio receiver on. Adjust the balance and
fader controls to check the performance of each indi-
vidual speaker. Note the speaker locations that are
not performing correctly. Go to Step 2.
(2) Turn the radio receiver off. Turn the ignition
switch to the Off position. Disconnect and isolate the
battery negative cable. Remove the radio receiver
from the instrument panel. If the vehicle is equipped
with the Infinity speaker package, also disconnect
the wire harness connectors at the power amplifier.
Check both the speaker feed (+) circuit and return (±)
circuit cavities for the inoperative speaker location(s)
at the radio receiver wire harness connectors for con-
tinuity to ground. In each case, there should be no
continuity. If OK, go to Step 3. If not OK, repair the
shorted speaker feed (+) and/or return (±) circuit(s) to
the speaker as required.
(3) If the vehicle is equipped with the Infinity
speaker package, go to Step 6. If the vehicle is
equipped with the standard speaker system, check
the resistance between the speaker feed (+) circuit
and return (±) circuit cavities of the radio receiverwire harness connectors for the inoperative speaker
location(s). The meter should read between 2 and 3
ohms (speaker resistance). If OK, go to Step 4. If not
OK, go to Step 5.
(4) Install a known good radio receiver. Connect
the battery negative cable. Turn the ignition switch
to the On position. Turn on the radio receiver and
test the speaker operation. If OK, replace the faulty
radio receiver. If not OK, turn the radio receiver off,
turn the ignition switch to the Off position, discon-
nect and isolate the battery negative cable, remove
the test radio receiver, and go to Step 5.
(5) Disconnect the wire harness connector at the
inoperative speaker. Check for continuity between
the speaker feed (+) circuit cavities of the radio
receiver wire harness connector and the speaker wire
harness connector. Repeat the check between the
speaker return (±) circuit cavities of the radio
receiver wire harness connector and the speaker wire
harness connector. In each case, there should be con-
tinuity. If OK, replace the faulty speaker. If not OK,
repair the open speaker feed (+) and/or return (±) cir-
cuit(s) as required.
(6) For each inoperative speaker location, check for
continuity between the speaker feed (+) circuit cavi-
ties of the radio receiver wire harness connectors and
the power amplifier wire harness connectors. Repeat
the check for each inoperative speaker location
between the speaker return (±) circuit cavities of the
radio receiver wire harness connectors and the power
amplifier wire harness connectors. In each case,
there should be continuity. If OK, go to Step 7. If not
OK, repair the open speaker feed (+) and/or return
(±) circuit(s) as required.
(7) Check for continuity between the two ground
circuit cavities of the power amplifier wire harness
connector and a good ground. There should be conti-
nuity. If OK, go to Step 8. If not OK, repair the open
ground circuit(s) to ground as required.
(8) Check the fused B(+) fuse for the power ampli-
fier in the junction block. If OK, go to Step 9. If not
OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(9) Install the radio receiver. Connect the battery
negative cable. Check for battery voltage at the fused
B(+) fuse for the power amplifier in the junction
block. If OK, go to Step 10. If not OK, repair the
open fused B(+) circuit to the Power Distribution
Center (PDC) fuse as required.
(10) Check for battery voltage at the two fused
B(+) circuit cavities of the power amplifier wire har-
ness connector. If OK, go to Step 11. If not OK, repair
the open fused B(+) circuit(s) to the power amplifier
fuse in the junction block as required.
(11) Turn the ignition switch to the On position.
Turn the radio receiver on. Check for battery voltage
WJAUDIO 8A - 23
SPEAKER (Continued)

Page 308 of 2199

DIAGNOSIS AND TESTING - CHIME WARNING
SYSTEM
Refer to the appropriate wiring information. Con-
ventional diagnostic methods may not prove conclu-
sive in the diagnosis of the instrument cluster or the
Programmable Communications Interface (PCI) data
bus network. The most reliable, efficient and accu-
rate means to diagnose the BCM and the PCI data
bus network inputs for the chime warning system
requires the use of a DRBIIItscan tool and the
appropriate diagnostic information.
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE AIRBAG SYSTEM BEFOREATTEMPTING ANY STEERING WHEEL, STEERING
COLUMN, OR INSTRUMENT PANEL COMPONENT
DIAGNOSIS OR SERVICE. DISCONNECT AND ISO-
LATE THE BATTERY NEGATIVE (GROUND) CABLE,
THEN WAIT TWO MINUTES FOR THE AIRBAG SYS-
TEM CAPACITOR TO DISCHARGE BEFORE PER-
FORMING FURTHER DIAGNOSIS OR SERVICE. THIS
IS THE ONLY SURE WAY TO DISABLE THE AIRBAG
SYSTEM. FAILURE TO TAKE THE PROPER PRE-
CAUTIONS COULD RESULT IN ACCIDENTAL AIR-
BAG DEPLOYMENT AND POSSIBLE PERSONAL
INJURY.
CHIME WARNING SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
NO SEAT BELT WARNING
CHIME WITH SEAT BELT
UNBUCKLED, BUT OTHER
CHIME FEATURES OK1. Seat belt switch ground
circuit open.1. Check for continuity between the ground circuit
of the wire harness connector for the seat belt
switch and a good ground. Repair the ground
circuit, if required.
2. Seat belt switch sense
circuit open.2. Check for continuity between the seat belt
switch sense circuit of the wire harness connector
for the seat belt switch and the body wire harness
junction block connector. Repair the seat belt
switch sense circuit, if required.
3. Faulty seat belt switch. 3. Check for continuity between the ground circuit
and the seat belt switch sense circuit of the seat
belt switch pigtail wire connector. There should be
continuity with the seat belt unbuckled. Replace
the faulty seat belt, if required.
SEAT BELT WARNING
CHIME WITH SEAT BELT
BUCKLED1. Seat belt switch sense
circuit shorted.1. With the wire harness connector for the seat
belt switch and the body wire harness junction
block connector disconnected, there should be no
continuity between the seat belt switch sense
circuit and a good ground. Repair the seat belt
switch sense circuit, if required.
2. Faulty seat belt switch. 2. Check for continuity between the ground circuit
and the seat belt switch sense circuit of the seat
belt switch pigtail wire connector. There should be
no continuity with the seat belt buckled. Replace
the faulty seat belt, if required.
WJCHIME/BUZZER 8B - 3
CHIME WARNING SYSTEM (Continued)

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Programmable Communications Interface (PCI) data
bus network.
For diagnosis of the HSM, MHSM or the PCI data
bus, a DRBIIItscan tool and the proper Diagnostic
Procedures manual are recommended. The HSM or
MHSM cannot be repaired and, if faulty or damaged,
it must be replaced.
OPERATION
The MSM receives hard wired inputs from the
power seat switch and the potentiometers on each of
the driver side power seat motors. The MSM receives
messages over the PCI data bus from the Driver
Door Module (DDM) (memory switch status), the
Powertrain Control Module (PCM) (vehicle speed sta-
tus), and the Body Control Module (seat belt switch
status).The MSM will prevent the seat memory recall
function from being initiated if the driver side seat
belt is buckled, if the transmission gear selector lever
is not in the Park or Neutral positions, or if the vehi-
cle is moving.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - HEATED SEAT
MODULE
Visually inspect the related wiring harness connec-
tors. Look for broken, bent, pushed out, or corroded
terminals. If any of the above conditions are present,
repair as necessary. If not, use a DRBIIItscan tool
and the proper Diagnostic Procedures Manual to test
the HSM or MHSM. For complete circuit diagrams,
refer toPower Seat Premium I/IIIin Wiring Dia-
grams.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the driver side front bucket seat from
the power seat track unit. Refer toBucket Seat
Track Adjusterin Body for the procedure.
(3) Lift the heated seat module off of the power
seat track and disconnect the power seat wire har-
ness connectors (Fig. 10).
(4) Remove the module from the bracket.
Fig. 9 Heated Seat Module Remove/Install
1 - NUT (4)
2 - SEAT CUSHION FRAME
3 - POWER SEAT TRACK
4 - STUD (4)
5 - MODULE
6 - BRACKET
Fig. 10 Heated Seat Module Remove/Install
1 - NUT (4)
2 - SEAT CUSHION FRAME
3 - POWER SEAT TRACK
4 - STUD (4)
5 - MODULE
6 - BRACKET
WJELECTRONIC CONTROL MODULES 8E - 11
MEMORY HEATED SEAT/MIRROR MODULE (Continued)

Page 321 of 2199

INSTALLATION
(1) Install the MHSM,HSM into the bracket.
(2) Position the heated seat module and mounting
bracket onto the power seat track.
(3) Reconnect the power seat wiring harness con-
nectors to the heated seat module.
(4) Install the driver side front bucket seat onto
the power seat track unit (Refer to 23 - BODY/
SEATS/SEAT TRACK ADJUSTER - INSTALLA-
TION).
(5) Reconnect the battery negative cable.
NOTE: If the vehicle is equipped with the optional
Memory System, following installation, it will be
necessary to initialize the Memory Heated Seat
Module (MHSM). In order to function properly, the
MHSM must ªlearnº the sensor values of each of
the power seat motor position transducers in each
of the adjuster hard stop positions. This is done by
performing the ªReset Guard Bandº procedure
using a DRBIIITscan tool and the proper Diagnostic
Procedures manual.
WARNING: THE ªRESET GUARD BANDº PROCE-
DURE WILL CAUSE THE DRIVER SIDE FRONT
SEAT TO AUTOMATICALLY ADJUST TO EACH OF
ITS TRAVEL LIMITS. BE CERTAIN THAT NO ONE IS
SEATED IN THE VEHICLE AND THAT THERE IS
NOTHING IN THE VEHICLE THAT WILL OBSTRUCT
SEAT MOVEMENT. FAILURE TO OBSERVE THIS
WARNING COULD RESULT IN PERSONAL INJURIES
AND/OR VEHICLE DAMAGE.
POWERTRAIN CONTROL
MODULE
DESCRIPTION
DESCRIPTION - PCM
The Powertrain Control Module (PCM) is located
in the engine compartment (Fig. 11). The PCM is
referred to as JTEC.
MODES OF OPERATION
As input signals to the Powertrain Control Module
(PCM) change, the PCM adjusts its response to the
output devices. For example, the PCM must calculate
different injector pulse width and ignition timing for
idle than it does for wide open throttle (WOT).
The PCM will operate in two different modes:
Open Loop and Closed Loop.
During Open Loop modes, the PCM receives input
signals and responds only according to preset PCMprogramming. Input from the oxygen (O2S) sensors
is not monitored during Open Loop modes.
During Closed Loop modes, the PCM will monitor
the oxygen (O2S) sensors input. This input indicates
to the PCM whether or not the calculated injector
pulse width results in the ideal air-fuel ratio. This
ratio is 14.7 parts air-to-1 part fuel. By monitoring
the exhaust oxygen content through the O2S sensor,
the PCM can fine tune the injector pulse width. This
is done to achieve optimum fuel economy combined
with low emission engine performance.
The fuel injection system has the following modes
of operation:
²Ignition switch ON
²Engine start-up (crank)
²Engine warm-up
²Idle
²Cruise
²Acceleration
²Deceleration
²Wide open throttle (WOT)
²Ignition switch OFF
The ignition switch On, engine start-up (crank),
engine warm-up, acceleration, deceleration and wide
open throttle modes are Open Loop modes. The idle
and cruise modes, (with the engine at operating tem-
perature) are Closed Loop modes.
IGNITION SWITCH (KEY-ON) MODE
This is an Open Loop mode. When the fuel system
is activated by the ignition switch, the following
actions occur:
Fig. 11 PCM Location
1 - PCM
2 - COOLANT TANK
8E - 12 ELECTRONIC CONTROL MODULESWJ
MEMORY HEATED SEAT/MIRROR MODULE (Continued)

Page 344 of 2199

STANDARD PROCEDURE - IGNITION-OFF
DRAW TEST
The term Ignition-Off Draw (IOD) identifies a nor-
mal condition where power is being drained from the
battery with the ignition switch in the Off position. A
normal vehicle electrical system will draw from five
to thirty-five milliamperes (0.005 to 0.035 ampere)
with the ignition switch in the Off position, and all
non-ignition controlled circuits in proper working
order. Up to thirty-five milliamperes are needed to
enable the memory functions for the Powertrain Con-
trol Module (PCM), digital clock, electronically tuned
radio, and other modules which may vary with the
vehicle equipment.
A vehicle that has not been operated for approxi-
mately twenty days, may discharge the battery to an
inadequate level. When a vehicle will not be used for
twenty days or more (stored), remove the IOD fuse
from the Power Distribution Center (PDC). This will
reduce battery discharging.Excessive IOD can be caused by:
²Electrical items left on.
²Faulty or improperly adjusted switches.
²Faulty or shorted electronic modules and compo-
nents.
²An internally shorted generator.
²Intermittent shorts in the wiring.
If the IOD is over thirty-five milliamperes, the
problem must be found and corrected before replac-
ing a battery. In most cases, the battery can be
charged and returned to service after the excessive
IOD condition has been corrected.
(1) Verify that all electrical accessories are off.
Turn off all lamps, remove the ignition key, and close
all doors. If the vehicle is equipped with an illumi-
nated entry system or an electronically tuned radio,
allow the electronic timer function of these systems
to automatically shut off (time out). This may take
up to three minutes. See the Electronic Module Igni-
tion-Off Draw Table for more information.
ELECTRONIC MODULE IGNITION-OFF DRAW (IOD) TABLE
ModuleTime Out?
(If Yes, Interval And Wake-Up Input)IODIOD After Time
Out
Radio No1to3
milliamperesN/A
Audio Power
AmplifierNoup to 1
milliampereN/A
Body Control Module
(BCM)No5.90
milliamperes
(max.)N/A
Powertrain Control
Module (PCM)No 0.95 milliampere N/A
Transmission Control
Module (TCM) 4.7L
w/45RFEYES (20 minutes, ignition on) 130 milliamperes 0.64 milliampere
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 tothree 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.
WJBATTERY SYSTEM 8F - 13
BATTERY (Continued)

Page 345 of 2199

(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 Power Distribution Center (PDC) and
then in the Junction Block (JB), one at a time until
the amperage reading becomes very low, or nonexist-
ent. Refer to the appropriate wiring information in
this service manual for complete PDC and JB fuse,
circuit breaker, and circuit identification. This will
isolate each circuit and identify the circuit that is the
source of the high-amperage IOD. If the amperage
reading remains high after removing and replacing
each fuse and circuit breaker, disconnect the wire
harness from the generator. If the amperage reading
now becomes very low or nonexistent, refer to Charg-
ing System for the proper charging system diagnosis
and testing procedures. After the high-amperage IOD
has been corrected, switch the multi-meter to pro-
gressively lower amperage scales and, if necessary,
repeat the fuse and circuit breaker remove-and-re-
place process to identify and correct all sources of
excessive IOD. It is now safe to select the lowest mil-
liampere 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 - CHECKING BATTERY
ELECTROLYTE LEVEL
The following procedure can be used to check the
battery electrolyte level.
(1) Remove the battery cell caps (Fig. 10).
(2) Look through the battery cap holes to deter-
mine the level of the electrolyte in the battery (Fig.
11). The electrolyte should be approximately 1 centi-
meter above the battery plates or until the hook
inside the battery cap holes is covered.
(3) Add only distilled water until the electrolyte
level is approx. one centimeter above the plates.
Fig. 10 Battery Caps - Export Battery
1 - BATTERY CAP
2 - BATTERY
Fig. 11 Hook Inside Battery Cap Holes - Export
Battery
1 - BATTERY SURFACE COVER
2 - HOOK
8F - 14 BATTERY SYSTEMWJ
BATTERY (Continued)

Page 349 of 2199

The battery cables (Fig. 17) or (Fig. 18) are large
gauge, stranded copper wires sheathed within a
heavy plastic or synthetic rubber insulating jacket.
The wire used in the battery cables combines excel-
lent flexibility and reliability with high electrical cur-
rent carrying capacity. Refer toWiring Diagrams
for battery cable wire gauge information.
A clamping type female battery terminal made of
soft lead is die cast onto one end of the battery cable
wire. A square headed pinch-bolt and hex nut are
installed at the open end of the female battery termi-
nal clamp. Large eyelet type terminals are crimped
onto the opposite end of the battery cable wire and
then solder-dipped. The battery positive cable wires
have a red insulating jacket to provide visual identi-
fication and feature a larger female battery terminal
clamp to allow connection to the larger battery posi-
tive terminal post. The battery negative cable wires
have a black insulating jacket and a smaller female
battery terminal clamp.
The battery cables cannot be repaired and, if dam-
aged or faulty they must be replaced. Both the bat-
tery positive and negative cables are available for
service replacement only as a unit with the battery
wire harness, which may include portions of the wir-
ing circuits for the generator and other components
on some models. Refer toWiring Diagramsfor more
information on the various wiring circuits included in
the battery wire harness for the vehicle being ser-
viced.
OPERATION
The battery cables connect the battery terminal
posts to the vehicle electrical system. These cables
also provide a path back to the battery for electrical
current generated by the charging system for restor-
ing the voltage 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 terminal 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 opposite ends of the battery cable
wires from the female battery terminal clamps pro-
vide secure and reliable connection of the battery
cables to the vehicle electrical system.
The battery positive cable terminal clamp is die
cast onto the ends of two wires. One wire has an eye-
let terminal that connects the battery positive cable
to the B(+) terminal stud of the Power Distribution
Center (PDC), and the other wire has an eyelet ter-
minal that connects the battery positive cable to the
B(+) terminal stud of the engine starter motor sole-
noid. The battery negative cable terminal clamp is
also die cast onto the ends of two wires. One wirehas an eyelet terminal that connects the battery neg-
ative cable to the vehicle powertrain through a stud
on the right side of the engine cylinder block. The
other wire has an eyelet terminal that connects the
battery negative cable to the vehicle body through a
ground screw on the right front fender inner shield,
near the battery.
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 cable. 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
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 load tested.
Refer to Standard Procedures for the proper battery
charging and load test procedures.
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 the engine from starting, remove the
Automatic Shut Down (ASD) relay. The ASD relay is
located in the Power Distribution Center (PDC), in
the engine compartment. See the fuse and relay lay-
out label affixed to the underside of the PDC cover
for ASD relay identification and location.
8F - 18 BATTERY SYSTEMWJ
BATTERY CABLE (Continued)

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