air JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

of the electronic modules are sending and receiving
the proper messages on the PCI data bus, and that
the memory system is receiving the proper hard
wired inputs and relaying the proper hard wired out-
puts to perform its functions.
DRIVER 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. 1). The ten-way power
seats are each equipped with a switch featuring two
knobs ganged together on the outboard seat cushion
side shield (Fig. 2).
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-
ing switch unit removal and installation, while both
knobs for the ten-way power seat switch unit must
be removed.
The individual switches in both power seat switch
units cannot be repaired. If one switch is damaged or
faulty, the entire power seat switch unit must be
replaced.
OPERATION
The power seat tracks of both the six-way and the
ten-way power seat systems can be adjusted in six
different ways using the power seat switches. The
ten-way system has the additional power seat
recliner switch integral to the power seat switch and
also has a separate, stand-alone switch to control the
power lumbar adjuster. See the owner's manual in
the vehicle glove box for more information on the
power seat switch functions and the seat adjusting
procedures.
When a power switch control knob or knobs are
actuated, a battery feed and a ground path are
applied through the switch contacts to the power seat
track or recliner adjuster motor. The selected
adjuster motor operates to move the seat track or
recliner through its drive unit in the selected direc-
tion until the switch is released, or until the travel
limit of the adjuster is reached. When the switch is
moved in the opposite direction, the battery feed and
ground path to the motor are reversed through the
switch contacts. This causes the adjuster motor to
run in the opposite direction.
No power seat switch should be held applied in any
direction after the adjuster has reached its travel
limit. The power seat adjuster motors each contain a
self-resetting circuit breaker to protect them from
overload. However, consecutive or frequent resetting
of the circuit breaker must not be allowed to con-
tinue, or the motor may be damaged.
Fig. 1 Six-Way Power Seat Switches - Typical
1 - OUTBOARD SEAT CUSHION SIDE SHIELD
2 - POWER SEAT TRACK SWITCHES
3 - MECHANICAL SEAT BACK RECLINER LEVER
Fig. 2 Ten-Way Power Seat Switches - Typical
1 - OUTBOARD CUSHION SIDE SHIELD
2 - POWER SEAT RECLINER SWITCH
3 - POWER SEAT TRACK SWITCH
4 - POWER LUMBAR SWITCH
WJPOWER SEAT SYSTEM 8N - 21
POWER SEAT SYSTEM (Continued)

LUMBAR CONTROL SWITCH
DESCRIPTION
The ten-way power seat option includes an electri-
cally operated lumbar support mechanism. A single
two-way momentary power lumbar switch is located
on the outboard seat cushion side shield of each front
seat, just forward of the other power seat switches
(Fig. 8). The power lumbar switch is secured to the
back of the seat cushion side shield with two screws,
and the switch paddle protrudes through a hole to
the outside of the shield. The switch paddle is located
in a shallow depression molded into the outer surface
of the seat cushion side shield that helps to shroud it
from unintentional actuation when entering or leav-
ing the vehicle.
The power lumbar switches cannot be adjusted or
repaired and, if faulty or damaged, they must be
replaced.
OPERATION
When the power lumbar switch paddle is actuated,
a battery feed and a ground path are applied through
the switch contacts to the power lumbar adjuster
motor. The motor operates to move the lumbar
adjuster through its drive unit in the selected direc-
tion until the switch is released, or until the travel
limit of the adjuster is reached. When the switch is
moved in the opposite direction, the battery feed and
ground path to the motor are reversed through the
switch contacts. This causes the motor to run in the
opposite direction.
The power lumbar switch should not be held
applied in either direction after the adjuster hasreached its travel limit. The power lumbar adjuster
motor contains a self-resetting circuit breaker to pro-
tect it from overload. However, consecutive or fre-
quent resetting of the circuit breaker must not be
allowed to continue, or the motor may be damaged.
DIAGNOSIS AND TESTING - POWER LUMBAR
SWITCH
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the power lumbar switch from the out-
board seat cushion side shield. Refer to the procedure
in this section of the manual.
(3) Use an ohmmeter to test the continuity of the
power lumbar switch in each switch position. See the
Power Lumbar Switch Continuity chart (Fig. 9). If
OK, refer toPower Lumbar Adjuster Diagnosis
and Testingin this group. If not OK, replace the
faulty power lumbar switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
Fig. 8 Ten-Way Power Seat Switches
1 - OUTBOARD CUSHION SIDE SHIELD
2 - POWER SEAT RECLINER SWITCH
3 - POWER SEAT TRACK SWITCH
4 - POWER LUMBAR SWITCH
Fig. 9 Power Lumbar Switch
POWER LUMBAR SWITCH
LEFT SWITCH
POSITIONRIGHT
SWITCH
POSITIONCONTINUITY
BETWEEN
Off Off 2-4, 3-5
Forward Rearward 3-5, 4-6
Rearward Forward 2-4, 3-6
8N - 24 POWER SEAT SYSTEMWJ

(2) Remove the three screws that secure the out-
board seat cushion side shield to the seat cushion
frame.
(3) Pull the outboard seat cushion side shield away
from the seat cushion frame far enough to access the
power lumbar switch wire harness connector.
(4) Disconnect the power seat wire harness connec-
tor from the power lumbar switch connector recepta-
cle (Fig. 10).
(5) Remove the two screws that secure the power
lumbar switch to the inside of the outboard seat
cushion side shield.
(6) Remove the power lumbar switch from the out-
board seat cushion side shield.
INSTALLATION
(1) Position the power lumbar switch onto the out-
board seat cushion side shield.
(2) Install and tighten the two screws that secure
the power lumbar switch to the inside of the out-
board seat cushion side shield. Tighten the screws to
1.5 N´m (14 in. lbs.).
(3) Reconnect the power seat wire harness connec-
tor to the power lumbar switch connector receptacle.
(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 cush-
ion frame. Tighten the screws to 1.5 N´m (14 in. lbs.).
(6) Reconnect the battery negative cable.
LUMBAR MOTOR
DESCRIPTION
The ten-way power seat option includes an electri-
cally operated lumbar support mechanism. The only
visible evidence of this option is the separate power
lumbar switch control paddle that is located on the
outboard seat cushion side shield, just forward of the
other power seat switch control knobs. The power
lumbar adjuster and motor are concealed beneath the
seat back trim cover and padding, where they are
secured to a molded plastic back panel and to the
seat back frame (Fig. 11).
The power lumbar adjuster cannot be repaired, and
is serviced only as a unit with the seat back frame. If
the power lumbar adjuster or the seat back frame
are damaged or faulty, the entire seat back frame
unit must be replaced.
Fig. 10 Power Lumbar Switch Remove/Install
1 - OUTBOARD SEAT CUSHION SIDE SHIELD
2 - POWER LUMBAR SWITCH
3 - WIRE HARNESS CONNECTOR
4 - SCREWS (2)
Fig. 11 Power Lumbar Adjuster
1 - SEAT BACK FRAME
2 - SEAT BACK PANEL
3 - LUMBAR MOTOR PIGTAIL TO SEAT WIRE HARNESS
4 - TIE WRAP
5 - SCREW (3)
6 - POWER LUMBAR ADJUSTER
7 - SEAT BACK TRIM COVER AND PADDING
WJPOWER SEAT SYSTEM 8N - 25
LUMBAR CONTROL SWITCH (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)

ing switch unit removal and installation, while both
knobs for the ten-way power seat switch unit must
be removed.
The individual switches in both power seat switch
units cannot be repaired. If one switch is damaged or
faulty, the entire power seat switch unit must be
replaced.
OPERATION
The power seat tracks of both the six-way and the
ten-way power seat systems can be adjusted in six
different ways using the power seat switches. The
ten-way system has the additional power seat
recliner switch integral to the power seat switch and
also has a separate, stand-alone switch to control the
power lumbar adjuster. See the owner's manual in
the vehicle glove box for more information on the
power seat switch functions and the seat adjusting
procedures.
When a power switch control knob or knobs are
actuated, a battery feed and a ground path are
applied through the switch contacts to the power seat
track or recliner adjuster motor. The selected
adjuster motor operates to move the seat track or
recliner through its drive unit in the selected direc-
tion until the switch is released, or until the travel
limit of the adjuster is reached. When the switch is
moved in the opposite direction, the battery feed and
ground path to the motor are reversed through the
switch contacts. This causes the adjuster motor to
run in the opposite direction.
No power seat switch should be held applied in any
direction after the adjuster has reached its travel
limit. The power seat adjuster motors each contain a
self-resetting circuit breaker to protect them fromoverload. However, consecutive or frequent resetting
of the circuit breaker must not be allowed to con-
tinue, or the motor may be damaged.
DIAGNOSIS AND TESTING - PASSENGER SEAT
SWITCH
For complete circuit diagrams, refer toWiring
Diagrams.
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the power seat switch from the out-
board seat cushion side shield. Refer to the procedure
in this section of the manual.
(3) Use an ohmmeter to test the continuity of the
power seat switch in each switch position. See the
Power Seat Switch Continuity chart (Fig. 15) or (Fig.
16). If OK, refer toDiagnosis and Testing Power
Seat TrackorDiagnosis and Testing Power Seat
Reclinerin this section. If not OK, replace the
faulty power seat switch.
Fig. 14 Ten-Way Power Seat Switches - Typical
1 - OUTBOARD CUSHION SIDE SHIELD
2 - POWER SEAT RECLINER SWITCH
3 - POWER SEAT TRACK SWITCH
4 - POWER LUMBAR SWITCH
Fig. 15 Rear Of Six-Way Power Seat Switch
SIX-WAY POWER SEAT SWITCH TEST
LEFT SWITCH
POSITIONRIGHT
SWITCH
POSITIONCONTINUITY
BETWEEN
OFF OFFB-N, B-J, B-M,
B-E, B-L, B-K
VERTICAL UPVERTICAL
DOWNA-J, A-N, B-M,
B-E
VERTICAL
DOWNVERTICAL UPA-E, A-M, B-N,
B-J
HORIZONTAL
FORWARDHORIZONTAL
REARWARDA-K, B-L
FRONT TILT
UPFRONT TILT
DOWNA-J, B-E
FRONT TILT
DOWNFRONT TILT
UPA-E, B-J
REAR TILT UPREAR TILT
DOWNA-N, B-M
REAR TILT
DOWNREAR TILT UP A-M, B-N
8N - 28 POWER SEAT SYSTEMWJ
PASSENGER SEAT 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)

(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 power seat recliner
adjuster motor and the power seat switch for shorts
or opens. If the circuits check OK, replace the faulty
power seat recliner unit. If the circuits are not OK,
repair the power seat wire harness as required.
POWER SEAT TRACK
DESCRIPTION
Both the six-way and the ten-way power seat
options include a single electrically operated power
seat track unit located under each front bucket seat
(Fig. 21). The power seat track unit replaces the
standard equipment manual seat tracks. The lower
half of the power seat track is secured at the front
with two screws to the floor panel seat cross member,
and at the rear with two screws to the floor panel.
Four nuts secure the bottom of the seat cushion
frame to four studs on the upper half of the power
seat track unit.
The power seat track unit cannot be repaired, and is
serviced only as a complete unit. If any component in
this unit is faulty or damaged, the entire power seat
track unit must be replaced. Refer toBucket Seat
Track Adjuster
in Body for the service procedure.
Fig. 20 Power Seat Recliner and Track - Typical
1 - SEAT BACK FRAME
2 - SEAT CUSHION PAD
3 - POWER RECLINER
4 - SEAT CUSHION FRAME
5 - SHIELD
6 - POWER SEAT TRACK ADJUSTER
Fig. 21 Power Seat Track - Typical
1 - DRIVE UNITS
2 - LOWER SEAT TRACKS
3 - POWER SEAT MOTORS
4 - SEAT CUSHION FRAME
WJPOWER SEAT SYSTEM 8N - 31
RECLINER MOTOR (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)

POWER WINDOWS
TABLE OF CONTENTS
page page
POWER WINDOWS
DESCRIPTION.........................33
OPERATION...........................34
DIAGNOSIS AND TESTING - POWER
WINDOWS...........................34
POWER WINDOW SWITCH
DESCRIPTION.........................36
OPERATION...........................36
DIAGNOSIS AND TESTING - POWER
WINDOW SWITCH.....................37REMOVAL.............................37
INSTALLATION.........................38
WINDOW MOTOR
DESCRIPTION.........................38
OPERATION...........................38
DIAGNOSIS AND TESTING - WINDOW
MOTOR .............................38
REMOVAL.............................39
INSTALLATION.........................39
POWER WINDOWS
DESCRIPTION
Power operated driver side and passenger side
front and rear door windows are standard factory-in-
stalled equipment on this model. The power window
system allows each of the door windows to be raised
or lowered electrically by operating a switch on the
trim panel for that door. Additionally, the master
switches on the driver side front door trim panel
allow all of the windows to be operated from the
driver seat position. A power window lockout switch
on the driver side front door trim panel will allow the
driver to disable all of the passenger door window
switches.
The power window system functionally operates
when the ignition switch is in the On position. How-
ever, a unique feature of this system will allow the
power windows to be operated for up to forty-five sec-
onds after the ignition switch is turned to the Off
position, or until a front door is opened, whichever
occurs first.
An auto-down feature allows the driver side front
door window to be lowered all the way, even if the
window switch is released. The driver side front door
window switch must be depressed in the down direc-
tion to a second detent to begin an auto-down event.
Depressing the switch again in any direction cancel
the auto-down event and begin movement in the
direction specified.
This group covers the following components of the
power window system:
²Power window switches
²Power window motors.
Certain functions and features of the power win-
dow system rely upon resources shared with other
electronic modules in the vehicle over the Program-mable Communications Interface (PCI) data bus net-
work. The PCI data bus network allows the sharing
of sensor information. This helps to reduce wire har-
ness complexity, 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 fea-
ture capabilities. For diagnosis of these electronic
modules or of the PCI data bus network, the use of a
DRB scan tool and the proper Diagnostic Procedures
manual are recommended.
The other electronic modules that may affect power
window system operation are as follows:
²Body Control Module (BCM)- (Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
ULES/BODY CONTROL/CENTRAL TIMER MODUL
- DESCRIPTION) for more information.
²Driver Door Module (DDM)-(Refer to 8 -
ELECTRICAL/ELECTRONIC CONTROL MOD-
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.
This group covers diagnosis and service of only the
electrical components in the power window system.
For service of mechanical components, such as the
regulator, lift plate, window tracks, or glass refer to
Body. 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. Follow-
ing are general descriptions of the major components
in the power window system.
WJPOWER WINDOWS 8N - 33

OPERATION
The power window system includes the Driver
Door Module (DDM) and Passenger Door Module
(PDM), which are mounted in their respective front
door, the rear door power window switches mounted
on the rear doors, and the power window motors
mounted to the window regulator in each door. The
DDM houses four master power window switches, the
power window lockout switch and the control logic for
the driver side front and rear door power windows.
The PDM houses the passenger side front door power
window switch and the control logic for the passenger
side front and rear door power windows.
When a master power window switch on the DDM
is used to operate a passenger side power window,
the DDM sends the window switch actuation mes-
sage to the PDM over the Programmable Communi-
cations Interface (PCI) data bus. The PDM responds
to these messages by sending control outputs to move
the passenger side power window motors. In addi-
tion, when the power window lockout switch in the
DDM is actuated to disable power window operation,
a lockout message is sent to the PDM over the PCI
data bus.
The Body Control Module (BCM) also supports and
controls certain features of the power window sys-
tem. The BCM receives a hard wired input from the
ignition switch. The programming in the BCM allows
it to process the information from this input and
send ignition switch status messages to the DDM
and the PDM over the PCI data bus. The DDM and
PDM use this information and hard wired inputs
from the front door ajar switches to control the light-
ing of the power window switch lamps, and to control
the operation of the power window after ignition-off
feature.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the power window system.
DIAGNOSIS AND TESTING - POWER
WINDOWS
Following are tests that will help to diagnose the
hard wired components and circuits of the power
window system. However, these tests may not prove
conclusive in the diagnosis of this system. In order to
obtain conclusive testing of the power window sys-
tem, the Programmable Communications Interface
(PCI) data bus network and all of the electronic mod-
ules that provide inputs to, or receive outputs from
the power window system components must be
checked.The most reliable, efficient, and accurate means to
diagnose the power window 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, and that
the power window motors are being sent the proper
hard wired outputs by the door modules for them to
perform their power window system functions.
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.
ALL WINDOWS INOPERATIVE
(1) Check the operation of the power lock switch
on the driver side front door. If all of the doors lock
and unlock, but none of the power windows operate,
use a DRB scan tool and the proper Diagnostic Pro-
cedures manual to check the Body Control Module
(BCM), the Driver Door Module (DDM) and the PCI
data bus for proper operation. If not OK, go to Step
2.
(2) Check the operation of the power lock switch
on the passenger side front door. If the passenger
doors lock and unlock, but the driver side front door
does not, go to Step 5. If all of the power locks and
power windows are inoperative from both front doors,
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.
8N - 34 POWER WINDOWSWJ
POWER WINDOWS (Continued)