wire diagram JEEP GRAND CHEROKEE 2002 WJ / 2.G Service Manual

DIAGNOSIS AND TESTING - POWER LOCK
MOTOR
Remember, the Driver Door Module (DDM) cir-
cuitry controls the output to the driver side front
door power lock motor. The Passenger Door Module
(PDM) circuitry controls the output to the power lock
motors for the remaining doors and the liftgate.
Refer to the appropriate wiring information. The wir-
ing 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.
(1) Check each power lock motor for correct opera-
tion while moving the power lock switch to both the
Lock and Unlock positions. If all of the power lock
motors are inoperative, go to Step 2. If one power
lock motor is inoperative, go to Step 3.
(2) If all of the power lock motors except the driver
side front door are inoperative, the problem may be
caused by one shorted motor. Disconnecting a shorted
power lock motor from the power lock circuit will
allow the good power lock motors to operate. Discon-
nect the wire harness connector from each PDM-con-
trolled power lock motor, one at a time, and recheck
both the lock and unlock functions by operating the
power lock switch. If all of the PDM-controlled power
lock motors are still inoperative after the above test,
check for a short or open circuit between the power
lock motors and the PDM. If disconnecting one power
lock motor causes the other motors to become func-
tional, go to Step 3 to test the power lock motor that
was last disconnected.
(3) Once it is determined which power lock motor
is inoperative, that motor can be tested as follows.
Disconnect the door or liftgate wire harness connec-
tor from the inoperative power lock motor. Apply 12
volts to the lock and unlock driver circuit cavities of
the power lock motor connector to check its operation
in one direction. Reverse the polarity to check the
motor operation in the opposite direction. If OK,
repair the shorted or open circuits between the lock
motor and the DDM or PDM as required. If not OK,
replace the faulty power lock motor.
POWER LOCK SWITCH
DESCRIPTION
The power lock motors are controlled by a two-way
momentary switch mounted on the trim panel of each
front door. Each power lock switch is illuminated by
a Light-Emitting Diode (LED) that is integral to the
switch paddle.
The driver side front door power lock switch is
integral to the Driver Door Module (DDM), and the
passenger side front door power lock switch is inte-
gral to the Passenger Door Module (PDM). The
power lock switches and their lamps cannot be
adjusted or repaired and, if faulty or damaged, the
entire DDM or PDM unit must be replaced. (Refer to
8 - ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/DOOR MODULE - DESCRIPTION).
OPERATION
The front door power lock switches provide a lock
and unlock signal to the door module circuitry. The
Driver Door Module (DDM) circuitry controls the out-
put to the driver side front door power lock motor,
while the Passenger Door Module (PDM) circuitry
controls the output to the passenger side front door,
both rear door and the liftgate power lock motors.
When the DDM-integrated power lock switch is
actuated, the DDM circuitry sends control outputs to
the driver side front door power lock motor and sends
a message to the PDM over the Programmable Com-
munications Interface (PCI) data bus to control the
output to the passenger side front door, both rear
door and the liftgate power lock motors. When the
PDM-integrated power lock switch is actuated, the
PDM circuitry sends control outputs to the passenger
side front door, both rear door and the liftgate power
lock motors and sends a message to the DDM over
the Programmable Communications Interface (PCI)
data bus to control the output to the driver side front
door power lock motor.
Each power lock switch is illuminated by a Light-
Emitting Diode (LED) when the ignition switch is
turned to the On position. See the owner's manual in
the vehicle glove box for more information on the fea-
tures, use and operation of the power lock switches.
8N - 8 POWER LOCKSWJ
POWER LOCK MOTOR (Continued)

ULES/DRIVER DOOR MODULE - DESCRIPTION)
for more information.
²Passenger Door Module (PDM)(Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/DRIVER DOOR MODULE - DESCRIPTION)
for more information.
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.
OPERATION
The Driver Door Module (DDM) and the Passenger
Door Module (PDM) each contain the power mirror
control logic for the mirror on its respective door. The
DDM also houses the power mirror switch. Each door
module controls the positioning of its respective out-
side mirror through hard wired outputs to that mir-
ror. When the power mirror switch on the DDM is
used to position the passenger side outside mirror,
the DDM sends mirror positioning messages to the
PDM over the Programmable Communications Inter-
face (PCI) data bus. The PDM responds to these mes-
sages by sending control outputs to move the
passenger side mirror accordingly.
Both the PDM and DDM respond to the defogger
switch status messages sent by the Body Control
Module (BCM) over the PCI data bus to control the
electric heater grids of their respective mirrors.
(Refer to 8 - ELECTRICAL/HEATED MIRRORS -
DESCRIPTION) for more information on this fea-
ture.
On models equipped with the optional memory sys-
tem, each door module also receives a hard wired
input from the two power mirror motor position
potentiometers that are integral to each power mir-
ror. Each door module then stores the Driver 1 and
Driver 2 mirror position information for its respective
mirror. When the DDM receives a Driver 1 or Driver
2 memory recall message from the memory switch on
the driver side front door trim panel or from the
Remote Keyless Entry (RKE) receiver in the PDM,
the DDM positions the driver side mirror and sends
a memory recall message back to the PDM over the
PCI data bus to position the passenger side mirror.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the power mirror system.
DIAGNOSIS AND TESTING - POWER MIRRORS
Following are tests that will help to diagnose the
hard wired components and circuits of the power mir-
ror system. However, these tests may not prove con-
clusive in the diagnosis of this system. In order toobtain conclusive testing of the power mirror system,
the Programmable Communications Interface (PCI)
data bus network and all of the electronic modules
that provide inputs to, or receive outputs from the
power mirror system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the power mirror system requires the use of
a DRB scan tool and the proper Diagnostic Proce-
dures manual. The DRB scan tool can provide confir-
mation that the PCI data bus is functional, that all
of the electronic modules are sending and receiving
the proper messages on the PCI data bus, that the
power mirror motors are being sent the proper hard
wired outputs, and that the mirror position potenti-
ometers are returning the proper outputs to the door
modules for them to perform their power mirror sys-
tem functions.
AUTOMATIC DAY/NIGHT
MIRROR
DESCRIPTION
DESCRIPTION - REAR VIEW MIRROR
An automatic day/night mirror system is an avail-
able factory-installed option on this model. The auto-
matic dimming inside day/night rear view mirror
system is a completely self-contained unit that
replaces the standard equipment inside rear view
mirror. This system will automatically change the
reflectance of the inside rear view mirror to protect
the driver from the unwanted headlight glare of
trailing vehicles while driving at night. The auto-
matic day/night inside mirror receives ignition
switched battery current through a fuse in the junc-
tion block, and will only operate when the ignition
switch is in the On position.
Vehicles equipped with the automatic day/night
mirror system are also available with an optional fac-
tory-installed automatic dimming outside rear view
mirror for the driver side of the vehicle. (Refer to 8 -
ELECTRICAL/POWER MIRRORS/SIDEVIEW MIR-
ROR - DESCRIPTION) for more information on this
option.
The automatic day/night mirror sensitivity cannot
be repaired or adjusted. If any component of this unit
is faulty or damaged, the entire automatic day/night
inside rear view mirror unit must be replaced. Refer
to the appropriate wiring information. The wiring
information includes wiring diagrams, proper wire
and connector repair procedures, details of wire har-
ness routing and retention, connector pin-out infor-
mation and location views for the various wire
harness connectors, splices and grounds.
8N - 12 POWER MIRRORSWJ
POWER MIRRORS (Continued)

DESCRIPTION - OUTSIDE REAR VIEW MIRROR
An automatic dimming outside rear view mirror is
an available factory-installed option for the driver
side of the vehicle, if the vehicle is also equipped
with the automatic day/night inside rear view mirror.
The automatic dimming outside mirror is completely
controlled by the circuitry of the automatic day/night
inside rear view mirror. The automatic dimming out-
side mirror will automatically change the reflectance
of the driver side outside rear view mirror to protect
the driver from the unwanted headlight glare of
trailing vehicles while driving at night. The auto-
matic dimming outside mirror will only operate when
the ignition switch is in the On position.
The automatic dimming outside mirror sensitivity
cannot be repaired or adjusted. If any component of
this unit is faulty or damaged, the entire automatic
dimming outside mirror unit must be replaced. (Refer
to 8 - ELECTRICAL/POWER MIRRORS/SIDEVIEW
MIRROR - DIAGNOSIS AND TESTING). 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.
OPERATION
OPERATION - REAR VIEW MIRROR
The automatic day/night mirror switch allows the
driver a manual control of whether the automatic
dimming feature is operational. This switch is a
momentary rocker-type switch located on the lower
rear-facing surface of the mirror housing. When Auto
is selected, a Light-Emitting Diode (LED) on the mir-
ror housing just to the right of the switch illuminates
to indicate that automatic day/night mirror is turned
on. When Off is selected, the LED is turned off. The
mirror also senses the backup lamp circuit, and will
automatically disable its self-dimming feature when-
ever the transmission gear selector is in the Reverse
position.
A thin layer of electrochromatic material between
two pieces of conductive glass make up the face of
the mirror. Two photocell sensors are used to monitor
light levels and adjust the reflectance of the mirror.
The ambient photocell sensor faces forward, to detect
the outside light levels. The headlamp sensor is
located on the mirror housing just to the left of the
switch and facing rearward, to detect the light level
received at the rear window side of the mirror. When
the difference between the two light levels becomes
too great (the light level received at the rear of themirror is much higher than that at the front of the
mirror), the mirror begins to darken.
On models with an optional driver side automatic
dimming outside mirror, the signal to control the
dimming of that mirror is generated by the auto-
matic day/night inside rear view mirror circuitry.
That signal is then delivered to the driver side out-
side rear view mirror on a hard wired circuit.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the automatic day/night mirror system.
OPERATION - OUTSIDE REAR VIEW MIRROR
The automatic dimming outside mirror is operated
by the same controls and circuitry as the automatic
day/night mirror. When the automatic day/night mir-
ror is turned on or off, the automatic dimming out-
side mirror is likewise turned on or off. Like in the
automatic day/night mirror, a thin layer of electro-
chromatic material between two pieces of conductive
glass make up the face of the automatic dimming
outside mirror. However, the signal to control the
dimming of the outside mirror is generated by the
automatic day/night inside rear view mirror circuitry.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the automatic dimming outside mirror.
DIAGNOSIS AND TESTING - AUTOMATIC DAY /
NIGHT MIRROR
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.
(1) Check the fused ignition switch output (run/
start) fuse in the junction block. If OK, go to Step 2.
If not OK, repair the shorted circuit or component as
required and replace the faulty fuse.
(2) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run/start) fuse in the junction block. If OK,
go to Step 3. If not OK, repair the open fused ignition
switch output (run/start) circuit to the ignition switch
as required.
(3) Disconnect the overhead wire harness connec-
tor from the automatic day/night mirror connector
receptacle. Check for battery voltage at the fused
ignition switch output (run/start) circuit cavity of the
overhead wire harness connector for the automatic
day/night mirror. If OK, go to Step 4. If not OK,
repair the open fused ignition switch output (run/
start) circuit to the fuse in the junction block as
required.
WJPOWER MIRRORS 8N - 13
AUTOMATIC DAY/NIGHT MIRROR (Continued)

DIAGNOSIS AND TESTING - SIDEVIEW
MIRROR
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.
BOTH MIRRORS INOPERATIVE
(1) Check the operation of the power lock switch
on the driver side front door. If all of the doors lock
and unlock, replace the faulty Driver Door Module
(DDM). If not OK, go to Step 2.
(2) Check the operation of the power lock switch
on the passenger side front door. If all of the doors
lock and unlock, replace the faulty DDM. If not OK,
go to Step 3.
(3) Check the fused B(+) fuse in the Power Distri-
bution Center (PDC). If OK, go to Step 4. If not OK,
repair the shorted circuit or component as required
and replace the faulty fuse.
(4) Check for battery voltage at the fused B(+) fuse
in the PDC. If OK, go to Step 5. If not OK, repair the
open fused B(+) circuit to the battery as required.
(5) Disconnect and isolate the battery negative
cable. Remove the trim panel from the driver side
front door. Disconnect the 15-way door wire harness
connector from the DDM connector receptacle. Check
for continuity between the ground circuit cavity of
the 15-way door wire harness connector for the DDM
and a good ground. There should be continuity. If
OK, go to Step 6. If not OK, repair the open ground
circuit to ground as required.
(6)
Reconnect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
15-way door wire harness connector for the DDM. If
OK, replace the faulty DDM. If not OK, repair the open
fused B(+) circuit to the fuse in the PDC as required.
ONE MIRROR INOPERATIVE
(1) If the one inoperative mirror is on the passen-
ger side, go to Step 2. If the one inoperative mirror is
on the driver side, go to Step 3.
(2)
Check if the passenger front door will lock and
unlock using the power lock switch on the driver side
front door. If OK, go to Step 3. If not OK, go to Step 6.
(3) Disconnect and isolate the battery negative
cable. Remove the trim panel from the front door.
Disconnect the 12-way mirror wire harness connector
from the door wire harness connector.
(4) Using two jumper wires, test the mirror as
shown in the Mirror Test chart (Fig. 2). If the mirror
tests OK, go to Step 5. If the mirror does not test
OK, replace the faulty mirror.(5) Disconnect the 12-way door wire harness con-
nector from the door module connector receptacle.
Check all of the circuits of the door wire harness
between the connector for the mirror and the connec-
tor for the door module for opens or shorts. If all of
the circuits are OK, replace the faulty door module.
If any of the circuits are not OK, repair the open or
shorted circuit(s) as required.
(6) Use a DRB scan tool and the proper Diagnostic
Procedures manual to test and repair the faulty Pro-
grammable Communications Interface (PCI) data bus
communication between the two door modules.
NO MIRROR HEAT
If one or both mirror heaters are inoperative,
(Refer to 8 - ELECTRICAL/HEATED MIRRORS -
DESCRIPTION).
(1) Disconnect and isolate the battery negative
cable. Remove the front door trim panel on the side
of the inoperative mirror heater.
(2) Disconnect the 12-way door wire harness con-
nector from the door module connector receptacle.
Check for continuity between the heater switched
ground circuit cavity and the heater 12V supply cir-
cuit cavity of the 12-way door wire harness connector
Fig. 2 Mirror Test
POWER MIRROR TEST TABLE
APPLY 12
VOLTS TO:APPLY
GROUND TO:MIRROR
REACTION
DRIVER SIDE
1 7 LEFT
7 1 RIGHT
87UP
7 8 DOWN
PASSENGER SIDE
1 7 LEFT
7 1 RIGHT
87UP
7 8 DOWN
8N - 16 POWER MIRRORSWJ
SIDEVIEW MIRROR (Continued)

²Ten-way power drivers and passenger seats
with Memory- This power seat option is standard
on Overland models and optional on Limited models.
This option includes a six-way adjustable seat cush-
ion track with power seat back recliners and power
lumbar supports. Heated Seats are standard with
this option.
Refer toHeated Seat Systemfor more informa-
tion on the heated seat option. Refer toMemory
Systemin the Memory System section of this group
for more information on the memory system.
The power seat system includes the following com-
ponents:
²Power lumbar adjuster (ten-way power seat
only)
²Power lumbar switch (ten-way power seat only)
²Power seat recliner (ten-way power seat only)
²Power seat switch
²Power seat track.
Refer toPower Seatin Wiring Diagrams for com-
plete circuit diagrams. Following are general descrip-
tions of the major components in the power seat/
memory seat system.
DESCRIPTION - MEMORY SYSTEM
An electronic memory system is standard equip-
ment on the Limited model. The memory system is
able to store and recall the driver side power seat
positions (including the power recliner position), and
both outside power mirror positions for two drivers.
For vehicles with a radio connected to the Program-
mable Communications Interface (PCI) data bus net-
work, the memory system is also able to store and
recall up to twenty - ten AM and ten FM - radio sta-
tion presets for two drivers. The memory system also
will store and recall the last station listened to for
each driver, even if it is not one of the twenty preset
stations.
The memory system will automatically return to
all of these settings when the corresponding num-
bered and color-coded button (Driver 1 - Black, or
Driver 2 - Gray) of the memory switch on the driver
side front door trim panel is depressed, or when the
doors are unlocked using the corresponding num-
bered and color-coded (Driver 1 - Black, or Driver 2 -
Gray) Remote Keyless Entry (RKE) transmitter. A
customer programmable feature of the memory sys-
tem allows the RKE recall of memory features to be
disabled in cases where there are more than two
drivers of the vehicle.
The memory system also has a customer program-
mable easy exit feature that will move the driver
seat rearward 55 millimeters (two inches) or to the
end of its travel, whichever occurs first, when the key
is removed from the ignition switch lock cylinder.A Memory Seat Module (MSM) or Memory Heated
Seat Module (MHSM) are used on this model to con-
trol and integrate the many electronic functions and
features included in the memory system. On vehicles
equipped with the heated seat system option, the
MHSM also controls the functions and features of
that system.
The memory system includes the following compo-
nents:
²Memory seat module (or memory heated seat
module)
²Memory switch
²Position potentiometers on both outside power
mirrors
²Position potentiometers on the driver side power
seat track and power seat recliner motors.
²Radio receiver (if PCI data bus capable).
Certain functions and features of the memory sys-
tem rely upon resources shared with other electronic
modules in the vehicle over the Programmable Com-
munications Interface (PCI) data bus network. The
PCI data bus network allows the sharing of sensor
information. This helps to reduce wire harness com-
plexity, internal controller hardware, and component
sensor current loads. At the same time, this system
provides increased reliability, enhanced diagnostics,
and allows the addition of many new feature capabil-
ities. For diagnosis of these electronic modules or of
the PCI data bus network, the use of a DRBtscan
tool and the proper Diagnostic Procedures manual
are recommended.
The other electronic modules that may affect mem-
ory system operation are as follows:
²Body Control Module (BCM)- Refer toBody
Control Modulein Electronic Control Modules for
more information.
²Driver Door Module (DDM)- Refer toDoor
Modulein Electronic Control Modules for more
information.
²Electronic Vehicle Information Center
(EVIC)- Refer toElectronic Vehicle Information
Centerin Overhead Console Systems for more infor-
mation.
²Passenger Door Module (PDM)- Refer to
Door Modulein Electronic Control Modules for
more information.
²Powertrain Control Module (PCM)- Refer to
Powertrain Control Modulein Electronic Control
Modules for more information.
²Radio Receiver- Refer toRadio Receiverin
Audio Systems for more information.
Refer toHeated Seat Systemfor more informa-
tion on this system. Refer toRemote Keyless Entry
Systemin Power Lock Systems for more information
on the RKE system. Refer toPower Mirrorin
Power Mirror Systems for more information on the
WJPOWER SEAT SYSTEM 8N - 19
POWER SEAT SYSTEM (Continued)

mirror position potentiometers. Refer toPower Seat
TrackandPower Seat Reclinerin the Power Seat
System section of this group for more information on
the driver side power seat position potentiometers.
Refer toPower Seatin Wiring Diagrams for com-
plete circuit diagrams. Following are general descrip-
tions of the remaining major components in the
factory-installed memory system.
OPERATION
OPERATION - POWER SEAT SYSTEM
The power seat system allows the driver and/or
front passenger seating positions to be adjusted elec-
trically and independently using the separate power
seat switches found on the outboard seat cushion
side shield of each front seat. See the owner's manual
in the vehicle glove box for more information on the
features, use and operation of the power seat system.
OPERATION - MEMORY SYSTEM
See the owner's manual in the vehicle glove box for
more information on the features, use and operation of
the memory system. For diagnosis of the MSM, the PCI
data bus, or the other electronic modules on the PCI
data bus that provide inputs and outputs for the mem-
ory system, the use of a DRBtscan tool and the proper
Diagnostic Procedures manual are recommended.
DRIVER AND PASSENGER DOOR MODULES
The Driver Door Module (DDM) monitors the mem-
ory switch through a hard wired circuit. It also mon-
itors the unlock messages from the Remote Keyless
Entry (RKE) receiver in the Passenger Door Module
(PDM) sent over the Programmable Communications
Interface (PCI) data bus. The DDM is programmed to
send memory recall messages and memory system
status messages over the PCI data bus to the other
electronic modules when it detects a memory recall
request.
Refer toDoor Modulein Electronic Control Mod-
ules for more information on the DDM and PDM.
ELECTRONIC VEHICLE INFORMATION CENTER
The Electronic Vehicle Information Center (EVIC)
serves as the user interface for the memory system. It
displays memory system status messages and provides
the user with the means for enabling and disabling
the many customer programmable features available
on the vehicle, including those for the memory system.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the EVIC. Refer toElectronic Vehicle Informa-
tion Centerin Overhead Console Systems for more
information on the EVIC.
DIAGNOSIS AND TESTING
DIAGNOSIS & TESTING - POWER SEAT
SYSTEM
Following are tests that will help to diagnose the
hard wired components and circuits of the power seat
system. However, if the vehicle is also equipped with
the optional memory system, these tests may not
prove conclusive in the diagnosis of the driver side
power seat. In order to obtain conclusive testing of
the driver side power seat with the memory system
option, the Programmable Communications Interface
(PCI) data bus network and all of the electronic mod-
ules that provide inputs to, or receive outputs from
the memory system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the driver side power seat with the memory
system option requires the use of a DRBtscan tool
and the proper Diagnostic Procedures manual. The
DRBtscan tool can provide confirmation that the
PCI data bus is functional, that all of the electronic
modules are sending and receiving the proper mes-
sages on the PCI data bus, and that the memory sys-
tem is receiving the proper hard wired inputs and
relaying the proper hard wired outputs to perform its
driver side power seat functions.
Before any testing of the power seat system is
attempted, the battery should be fully-charged and
all of the power seat system wire harness connections
and pins cleaned and tightened to ensure proper cir-
cuit continuity and ground paths. For complete cir-
cuit diagrams, refer toPower Seatin Wiring
Diagrams.
With the dome lamp on, apply the power seat
switch in the direction of the failure. If the dome
lamp dims, the seat may be jamming. Check under
and behind the seat for binding or obstructions. If
the dome lamp does not dim, proceed with testing of
the individual components and circuits.
DIAGNOSIS & TESTING - MEMORY SYSTEM
Following are tests that will help to diagnose the
components and circuits that provide hard wired
inputs to the memory system. However, these tests
may not prove conclusive in the diagnosis of this sys-
tem. In order to obtain conclusive testing of the
memory system, the Programmable Communications
Interface (PCI) data bus network and all of the elec-
tronic modules that provide inputs to, or receive out-
puts from the memory system components must be
checked.
The most reliable, efficient, and accurate means to
diagnose the memory system requires the use of a
DRBtscan tool and the proper Diagnostic Proce-
dures manual. The DRBtscan tool can provide con-
firmation that the PCI data bus is functional, that all
8N - 20 POWER SEAT SYSTEMWJ
POWER SEAT SYSTEM (Continued)

OPERATION
The power lumbar adjuster mechanism includes a
reversible electric motor that is secured to the
inboard side of the seat back panel and is connected
to a worm-drive gearbox. The motor and gearbox
operate the lumbar adjuster mechanism in the center
of the seat back by extending and retracting a cable
that actuates a lever. The action of this lever com-
presses or relaxes a grid of flexible slats. The more
this grid is compressed, the more the slats bow out-
ward against the center of the seat back padding,
providing additional lumbar support.
DIAGNOSIS AND TESTING - POWER LUMBAR
ADJUSTER
Actuate the power lumbar switch to move the
power lumbar adjuster in each direction. The power
lumbar adjuster should move in both directions. It
should be noted that the power lumber adjuster nor-
mally operates very quietly and exhibits little visible
movement. If the power lumbar adjuster fails to oper-
ate in only one direction, move the adjuster a short
distance in the opposite direction and test again to be
certain that the adjuster is not at its travel limit. If
the power lumbar adjuster still fails to operate in
only one direction, refer toDiagnosis and Testing
Power Lumbar Switchin this group. If the power
lumbar adjuster fails to operate in either direction,
perform the following tests. For complete circuit dia-
grams, refer toWiring Diagrams.
(1) Check the power seat circuit breaker in the
junction block. If OK, go to Step 2. If not OK, replace
the faulty power seat circuit breaker.
(2) Check for battery voltage at the power seat cir-
cuit breaker in the junction block. If OK, go to Step
3. If not OK, repair the open fused B(+) circuit to the
fuse in the Power Distribution Center as required.
(3) Remove the outboard seat cushion side shield
from the seat. Disconnect the seat wire harness con-
nector from the power lumbar switch connector
receptacle. Check for battery voltage at the fused
B(+) circuit cavity of the power seat wire harness
connector for the power lumbar switch. If OK, go to
Step 4. If not OK, repair the open fused B(+) circuit
to the power seat circuit breaker in the junction
block as required.
(4) Check for continuity between the ground cir-
cuit cavity of the power seat wire harness connector
for the power lumbar switch and a good ground.
There should be continuity. If OK, go to Step 5. If not
OK, repair the open ground circuit to ground as
required.
(5) Test the power lumbar switch. Refer toDiag-
nosis and Testing Power Lumbar Switchin this
group. If the switch tests OK, test the circuits of the
power seat wire harness between the power lumbaradjuster motor and the power lumbar switch for
shorts or opens. If the circuits check OK, replace the
faulty seat back frame assembly. If the circuits are
not OK, repair the power seat wire harness as
required.
MEMORY SET SWITCH
DESCRIPTION
Vehicles equipped with the memory system have a
memory switch mounted to the driver side front door
trim panel (Fig. 12). This switch is used to set and
recall all of the memory system settings for up to two
drivers. The memory switch is a resistor multiplexed
unit that is hard wired to the Driver Door Module
(DDM), which is also located on the driver side front
door trim panel. The DDM sends out the memory
system set and recall requests to the other electronic
modules over the Programmable Communications
Interface (PCI) data bus.
The memory switch cannot be adjusted or repaired
and, if faulty or damaged, it must be replaced. For
complete circuit diagrams, refer toWiring Diagrams
.
OPERATION
The memory switch has three momentary switch
buttons labeled Set, 1 and 2. The Driver 1 and Driver
2 buttons are back-lit with Light-Emitting Diodes
Fig. 12 WJ/WG MEMORY SELECT/SET SWITCH
1 - DRIVER TRIM PANEL
2 - MEMORY SWITCH
8N - 26 POWER SEAT SYSTEMWJ
LUMBAR MOTOR (Continued)

(LED) for visibility, and are also color-coded to coin-
cide with the color-coded Driver 1 and Driver 2
Remote Keyless Entry (RKE) transmitters. The
Driver 1 memory switch button and RKE transmitter
are black, and the Driver 2 memory switch button
and RKE transmitter are gray. The memory switch
Set button also has an LED that will illuminate and
flash to indicate that the memory system is in the set
mode. This LED will automatically be extinguished
when a set request has been successfully completed.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the memory switch. For diagnosis of the memory
switch, the DDM or the PCI data bus, the use of a
DRB scan tool and the proper Diagnostic Procedures
manual are recommended.
DIAGNOSIS AND TESTING - MEMORY SWITCH
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the driver side front door trim panel.
Refer to the Body section for the procedure.
(3) Disconnect the memory switch wire harness
connector from the driver door module connector
receptacle.
(4) Use an ohmmeter to test the resistances of the
memory switch in each switch position. See the Mem-
ory Switch Test chart MEMORY SWITCH TEST . If
OK, refer toMemory System Diagnosis and Test-
ingin this group. If not OK, replace the faulty mem-
ory switch.
MEMORY SWITCH TEST
MEMORY
SWITCH
POSITIONRESISTANCE
BETWEENRESISTANCE
RANGE
(OHMS)
NEUTRAL A&D 14000   1%
MEMORY 1 A&B 4600   1%
MEMORY 2 A&B 1700   1%
SET A&B 300   1%
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the trim panel from the driver side
front door. Refer toFront Door Trim Panelin Body
for the procedure.
(3) Disconnect the memory switch wire harness
connector from the driver door module connector
receptacle.
(4) Remove the two screws that secure the memory
switch to the back of the driver side front door trim
panel.(5) Remove the memory switch from the back of
the driver side front door trim panel.
INSTALLATION
(1) Position the memory switch onto the back of
the driver side front door trim panel.
(2) Install and tighten the two screws that secure
the memory switch to the back of the driver side
front door trim panel. Tighten the screws to 2.2 N´m
(20 in. lbs.).
(3) Reconnect the memory switch wire harness
connector to the driver door module connector recep-
tacle.
(4) Install the trim panel onto the driver side front
door. Refer toFront Door Trim Panelin Body for
the procedure.
(5) Reconnect the battery negative cable.
PASSENGER SEAT SWITCH
DESCRIPTION
Two different power seat switches are used on this
vehicle, depending upon the optional power seat sys-
tem installed in the vehicle. The six-way power seats
are each equipped with a switch featuring three
switch control knobs ganged together on the outboard
seat cushion side shield (Fig. 13). The ten-way power
seats are each equipped with a switch featuring two
knobs ganged together on the outboard seat cushion
side shield (Fig. 14).
The switch units for both power seat types are
secured to the back of the seat cushion side shield
with two screws. However, the control knobs for the
six-way power seat switch unit remain installed dur-
Fig. 13 Six-Way Power Seat Switches - Typical
1 - OUTBOARD SEAT CUSHION SIDE SHIELD
2 - POWER SEAT TRACK SWITCHES
3 - MECHANICAL SEAT BACK RECLINER LEVER
WJPOWER SEAT SYSTEM 8N - 27
MEMORY SET SWITCH (Continued)

(4) Position the outboard seat cushion side shield
onto the seat cushion frame
(5) Install and tighten the three screws that secure
the outboard seat cushion side shield to the seat
cushion frame. Tighten the screws to 1.5 N´m (14 in.
lbs.).
(6) On models with the ten-way power seat system
only, position the power seat and power recliner
switch knobs onto the switch stems and push on
them firmly and evenly until they snap into place.
(7) Reconnect the battery negative cable.
RECLINER MOTOR
DESCRIPTION
The ten-way power seat option includes an electri-
cally operated seat back recliner mechanism. The
only visible evidence of this option is the separate
power seat recliner switch control knob that is
located on the outboard seat cushion side shield, just
behind the other power seat switch control knob. The
power seat recliner switch is integral to the ten-way
power seat switch unit, but is actuated with a sepa-
rate switch knob.
The power seat recliner unit is mounted in the
place of a seat hinge on the outboard side of the seat
(Fig. 20). The upper hinge plate of the power seat
recliner mechanism is secured with two screws to the
seat back frame and is concealed beneath the seat
back trim cover and padding. The lower hinge plate
and the motor and drive unit of the power seat
recliner mechanism is secured with two screws to the
seat cushion frame, and is concealed by the outboard
seat cushion side shield.
The power seat recliner cannot be repaired. If the
unit is faulty or damaged, it must be replaced. Refer
toBucket Seat Reclinerin Body for the service
procedure.
OPERATION
The power seat recliner includes a reversible elec-
tric motor that is secured to the lower hinge plate of
the recliner unit. The motor is connected to a gearbox
that moves the upper hinge plate of the power seat
recliner through a screw-type drive unit. The driver
side power seat recliner motor used on models
equipped with the optional memory system also has
a position potentiometer integral to the motor assem-
bly, which electronically monitors the motor position.
DIAGNOSIS AND TESTING - RECLINER MOTOR
Actuate the power seat recliner switch to move the
power seat recliner adjuster in each direction. The
power seat recliner adjuster should move in both
directions. If the power seat recliner adjuster fails to
operate in only one direction, move the adjuster a
short distance in the opposite direction and test
again to be certain that the adjuster is not at its
travel limit. If the power seat recliner adjuster still
fails to operate in only one direction, refer toPower
Seat Switch Diagnosis and Testingin this group.
If the power recliner adjuster fails to operate in
either direction, perform the following tests. For com-
plete circuit diagrams, refer toWiring Diagrams.
(1) Check the power seat circuit breaker in the
junction block. If OK, go to Step 2. If not OK, replace
the faulty power seat circuit breaker.
Fig. 18 Six-Way Power Seat Switches Remove/
Install
1 - SEAT SIDE SHIELD
2 - POWER SEAT SWITCH
3 - SCREWS
Fig. 19 Ten-Way Power Seat Switches Remove/
Install
1 - POWER SEAT SWITCH
2 - SCREWS (2)
3 - POWER LUMBAR SWITCH
4 - SEAT CUSHION SIDE SHIELD
5 - WIRE HARNESS CONNECTOR
8N - 30 POWER SEAT SYSTEMWJ
PASSENGER SEAT SWITCH (Continued)

OPERATION
The power seat track unit includes three reversible
electric motors that are secured to the upper half of
the track unit. Each motor moves the seat adjuster
through a combination of worm-drive gearboxes and
screw-type drive units. Each of the three driver side
power seat track motors used on models equipped
with the optional memory system also has a position
potentiometer integral to the motor assembly, which
electronically monitors the motor position.
The front and rear of the seat are operated by two
separate vertical adjustment motors. These motors
can be operated independently of each other, tilting
the entire seat assembly forward or rearward; or,
they can be operated in unison by selecting the
proper power seat switch functions, which will raise
or lower the entire seat assembly. The third motor is
the horizontal adjustment motor, which moves the
seat track in the forward and rearward directions.
DIAGNOSIS AND TESTING - POWER SEAT
TRACK
Following are tests that will help to diagnose the
hard wired components and circuits of the power seat
system. However, if the vehicle is also equipped with
the optional memory system, these tests may not
prove conclusive in the diagnosis of the driver side
power seat. In order to obtain conclusive testing of
the driver side power seat with the memory system
option, the Programmable Communications Interface
(PCI) data bus network and all of the electronic mod-
ules that provide inputs to, or receive outputs from
the memory system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the driver side power seat with the memory
system option requires the use of a DRBtscan tool
and the proper Diagnostic Procedures manual. The
DRBtscan tool can provide confirmation that the
PCI data bus is functional, that all of the electronic
modules are sending and receiving the proper mes-
sages on the PCI data bus, and that the memory sys-
tem is receiving the proper hard wired inputs and
relaying the proper hard wired outputs to perform its
driver side power seat functions.Actuate the power seat switch to move all three
power seat track adjusters in each direction. The
power seat track adjusters should move in each of
the selected directions. If a power seat track adjuster
fails to operate in only one direction, move the
adjuster a short distance in the opposite direction
and test again to be certain that the adjuster is not
at its travel limit. If the power seat track adjuster
still fails to operate in only one direction, refer to
Power Seat Switch Diagnosis and Testingin this
group. If the power seat track adjuster fails to oper-
ate in more than one direction, perform the following
tests. For complete circuit diagrams, refer toWiring
Diagrams.
(1) Check the power seat circuit breaker in the
junction block. If OK, go to Step 2. If not OK, replace
the faulty power seat circuit breaker.
(2) Check for battery voltage at the power seat cir-
cuit breaker in the junction block. If OK, go to Step
3. If not OK, repair the open fused B(+) circuit to the
fuse in the Power Distribution Center as required.
(3) Remove the outboard seat cushion side shield
from the seat. Disconnect the seat wire harness con-
nector from the power seat switch connector recepta-
cle. Check for battery voltage at the fused B(+)
circuit cavity of the power seat wire harness connec-
tor for the power seat switch. If OK, go to Step 4. If
not OK, repair the open fused B(+) circuit to the
power seat circuit breaker in the junction block as
required.
(4) Check for continuity between the ground cir-
cuit cavity of the power seat wire harness connector
for the power seat switch and a good ground. There
should be continuity. If OK, go to Step 5. If not OK,
repair the open ground circuit to ground as required.
(5) Test the power seat switch. Refer toPower
Seat Switch Diagnosis and Testingin this group.
If the switch tests OK, test the circuits of the power
seat wire harness between the inoperative power seat
track adjuster motor and the power seat switch for
shorts or opens. If the circuits check OK, replace the
faulty power seat track unit. If the circuits are not
OK, repair the power seat wire harness as required.
8N - 32 POWER SEAT SYSTEMWJ
POWER SEAT TRACK (Continued)