Power System JEEP GRAND CHEROKEE 2003 WJ / 2.G Workshop Manual

See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the power lock system.
OPERATION - REMOTE KEYLESS ENTRY
SYSTEM
The Passenger Door Module (PDM) contains the
RKE system control logic and the RKE receiver.
When the RKE receiver recognizes a Lock, Unlock or
Panic message from a valid RKE transmitter, the
RKE receiver provides that input to the PDM. The
PDM circuitry and programming responds by sending
the proper messages to the other electronic modules
over the Programmable Communications Interface
(PCI) data bus.
When an RKE lock message is received, the doors
and the liftgate lock, the interior lighting fades to off,
the horn chirps (if this feature is enabled), the exte-
rior lamps flash (if this feature is enabled) and, if the
vehicle is so equipped, the Vehicle Theft Security
System (VTSS) is armed. When an RKE unlock mes-
sage is received, the driver side front door (or all
doors and the liftgate if this feature is enabled)
unlock, the interior lighting is turned on and, if the
vehicle is so equipped, the VTSS is disarmed. If the
vehicle is equipped with the Memory System and the
RKE Linked to Memory feature is enabled, the RKE
unlock message also recalls the driver seat, outside
mirror and radio settings assigned to the RKE trans-
mitter that sent the unlock signal.
When an RKE panic message is received, it causes
the exterior lamps (including the headlights) to flash,
and the horn to pulse for about three minutes, or
until a second panic message is received. A vehicle
speed of about 24 kilometers-per-hour (15 miles-per-
hour) will also cancel the panic event.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the RKE system.
OPERATION - LIFTGATE FLIP-UP GLASS
POWER RELEASE SYSTEM
When the liftgate mounted flip-up glass release
switch is depressed, battery current is directed to the
electric release motor that is integral to the flip-up
glass latch located inside the liftgate. When the
release motor is energized the latch releases and the
flip-up glass can be opened. A liftgate flip-up glass
limit switch is integral to the liftgate latch actuator
mechanism. The limit switch automatically enables
or disables the liftgate flip-up glass power release cir-
cuitry, depending upon the position of the liftgate
latch lock mechanism. When the liftgate latch is
unlocked, the limit switch closes and battery current
is available at the release switch. When the liftgatelatch is locked , the limit switch opens, and the
release switch is disabled.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the liftgate flip-up glass power release system.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - POWER LOCK
SYSTEM
Following are tests that will help to diagnose the
hard wired components and circuits of the power lock
system. However, these tests may not prove conclu-
sive in the diagnosis of this system. In order to
obtain conclusive testing of the power lock 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 lock system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the power lock system requires the use of a
DRBIIItscan tool and the proper Diagnostic Proce-
dures manual. The DRBIIItscan tool can provide
confirmation that the PCI data bus is functional, that
all of the electronic modules are sending and receiv-
ing the proper messages on the PCI data bus, and
that the power lock motors are being sent the proper
hard wired outputs by the door modules for them to
perform their power lock system functions.
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.
PRELIMINARY DIAGNOSIS
As a preliminary diagnosis for the power lock sys-
tem, note the system operation while you actuate
both the Lock and Unlock functions with the power
lock switches and with the Remote Keyless Entry
(RKE) transmitter. Then, proceed as follows:
²If the entire power lock system fails to function
with either the power lock switches or the RKE
transmitter, check the fused B(+) fuse in the Power
Distribution Center. If the fuse is OK, proceed to
diagnosis of the door modules. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/
DOOR MODULE - DIAGNOSIS AND TESTING).
²If the power lock system functions with both
power lock switches, but not with the RKE transmit-
ter, proceed to diagnosis of the Remote Keyless Entry
(RKE) system. (Refer to 8 - ELECTRICAL/POWER
LOCKS - DIAGNOSIS AND TESTING - REMOTE
KEYLESS ENTRY SYSTEM).
WJPOWER LOCKS 8N - 5
POWER LOCKS (Continued)

²If the power lock system functions with the RKE
transmitter, but not with one or both power lock
switches, proceed to diagnosis of the door modules.
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/DOOR MODULE - DIAGNOSIS
AND TESTING).
²If the driver side power lock switch operates
only the driver side front door power lock motor, but
all other power lock motors operate with the passen-
ger side power lock switch or the RKE transmitter,
use a DRBIIItscan tool and the appropriate diagnos-
tic information to diagnose the Programmable Com-
munications Interface (PCI) data bus.
²If only one power lock motor fails to operate
with both power lock switches and the RKE trans-
mitter, proceed to diagnosis of the power lock motor.
(Refer to 8 - ELECTRICAL/POWER LOCKS/POWER
LOCK MOTOR - DIAGNOSIS AND TESTING).
DIAGNOSIS AND TESTING - REMOTE KEYLESS
ENTRY SYSTEM
Following are tests that will help to diagnose the
Remote Keyless Entry (RKE) system. However, these
tests may not prove conclusive in the diagnosis of
this system. In order to obtain conclusive testing of
the RKE 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 RKE system components must be
checked.
The most reliable, efficient, and accurate means to
diagnose the RKE system requires the use of a
DRBIIItscan tool and the appropriate diagnostic
information. The DRBIIItscan tool can provide con-
firmation 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 RKE receiver is being sent the proper radio fre-
quency signals by the RKE transmitters to perform
its RKE system functions.
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.
PRELIMINARY DIAGNOSIS
As a preliminary diagnosis for the RKE system,
note the system operation while you perform both the
Lock and Unlock functions with the power lock
switches and with the Remote Keyless Entry (RKE)
transmitter. Then, proceed as follows:
²If the entire power lock system fails to function
with either the power lock switches or the RKE
transmitter, check the fused B(+) fuse in the PowerDistribution Center. If the fuse is OK, proceed to the
diagnosis for the door modules. (Refer to 8 - ELEC-
TRICAL/ELECTRONIC CONTROL MODULES/
DOOR MODULE - DIAGNOSIS AND TESTING).
²If the power lock system functions with both
power lock switches, but not with the RKE transmit-
ter, proceed to the diagnosis for the RKE transmitter.
(Refer to 8 - ELECTRICAL/POWER LOCKS/RE-
MOTE KEYLESS ENTRY TRANSMITTER - DIAG-
NOSIS AND TESTING).
²If the driver side power lock switch operates
only the driver side front door power lock motor, but
all other power lock motors operate with the passen-
ger side power lock switch or the RKE transmitter,
use a DRBIIItscan tool and the appropriate diagnos-
tic information to diagnose the Programmable Com-
munications Interface (PCI) data bus.
If the problem being diagnosed involves only the
Sound Horn on Lock or the Flash Lights with Locks
features, be certain that these programmable fea-
tures are enabled. If the features are enabled and the
service horn and turn signals still operate, the Body
Control Module (BCM) and the PCI data bus must be
tested. For diagnosis of the BCM or the PCI data
bus, the use of a DRBIII scan tool and the appropri-
ate diagnostic information are required.
DIAGNOSIS AND TESTING - LIFTGATE FLIP-UP
GLASS POWER RELEASE SYSTEM
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.
(1) Check the fused B(+) fuse in the Junction
Block (JB). If OK, go to Step 2. If not OK, repair the
shorted circuit or component as required and replace
the faulty fuse.
(2) Check for battery voltage at the fused B(+) fuse
in the JB. If OK, go to Step 3. If not OK, repair the
open fused B(+) circuit to the Power Distribution
Center (PDC) as required.
(3) Disconnect the liftgate wire harness connector
for the liftgate lock motor and flip-up glass limit
switch from the motor and switch connector recepta-
cle. Check for battery voltage at the fused B(+) cir-
cuit cavity of the liftgate wire harness connector for
the liftgate lock motor and flip-up glass limit switch.
If OK, go to Step 4. If not OK, repair the open fused
B(+) circuit between the liftgate lock motor and
flip-up glass limit switch and the JB as required.
(4) Check for continuity between the two liftgate
flip-up glass limit switch terminals. There should be
continuity with the liftgate latch unlocked, and no
continuity with the latch locked. If OK, go to Step 5.
8N - 6 POWER LOCKSWJ
POWER LOCKS (Continued)

If not OK, replace the faulty liftgate latch actuator
(brainplate) unit.
(5) Disconnect the liftgate wire harness connector
for the liftgate flip-up glass release switch from the
switch connector receptacle. With the liftgate latch
unlocked, check for battery voltage at the liftgate
flip-up glass limit switch output circuit cavity of the
liftgate wire harness connector for the release switch.
If OK, go to Step 6. If not OK, repair the open lift-
gate flip-up glass limit switch output circuit between
the release switch and the limit switch as required.
(6) Check for continuity between the two terminals
of the liftgate flip-up glass release switch. There
should be no continuity. Depress the switch, there
should now be continuity. If OK, go to Step 7. If not
OK, replace the faulty liftgate flip-up glass release
switch.
(7) Disconnect the liftgate wire harness connector
for the liftgate flip-up glass latch motor from the
motor connector receptacle. Check for continuity
between the ground circuit cavity of the liftgate wire
harness connector for the latch motor and a good
ground. There should be continuity. If OK, go to Step
8. If not OK, repair the open ground circuit to ground
as required.
(8) With the liftgate latch unlocked and the flip-up
glass release switch depressed, check for battery volt-
age at the liftgate flip-up glass release switch output
circuit cavity of the liftgate wire harness connector
for the latch motor. If OK, replace the faulty liftgate
flip-up glass latch unit. If not OK, repair the open
liftgate flip-up glass release switch output circuit
between the latch motor and the release switch as
required.
DOOR CYLINDER LOCK
SWITCH
DESCRIPTION
The driver cylinder lock switch is integral to the
key lock cylinder inside the driver side front door.
The driver cylinder lock switch is a resistive multi-
plexed switch that is hard wired between a body
ground and the Driver Door Module (DDM) through
the front door wire harness. It maintains a path to
ground, and changes voltages through an internal
resistor when the lock cylinder is rotated to the lock
or unlock position.
The driver cylinder lock switch cannot be adjusted
or repaired and, if faulty or damaged, the driver side
front door lock cylinder unit must be replaced. (Refer
to 23 - BODY/DOOR - FRONT/LOCK CYLINDER -
REMOVAL) and (Refer to 23 - BODY/DOOR -
FRONT/LOCK CYLINDER - INSTALLATION). Refer
to the appropriate wiring information. The wiringinformation includes wiring diagrams, proper wire
and connector repair procedures, further details on
wire harness routing and retention, as well as pin-
out and location views for the various wire harness
connectors, splices and grounds.
OPERATION
The driver cylinder lock switch is actuated by the
key lock cylinder when the key is inserted in the lock
cylinder and turned to the unlock position. The
driver cylinder lock switch maintains a path to
ground and changes voltages through an internal
resistor for the DDM when the driver door key lock
cylinder is in the lock or unlock position. The DDM
reads the switch status through an internal pull-up,
then sends the proper switch status messages to
other electronic modules over the Programmable
Communications Interface (PCI) data bus network.
The driver cylinder lock switch unlock status mes-
sage is used by the BCM as an input for Vehicle
Theft Security System (VTSS) operation and interior
lighting.
POWER LOCK MOTOR
DESCRIPTION
Power operated front door, rear door, and liftgate
locking mechanisms are standard equipment on this
model. The lock mechanisms are actuated by a
reversible electric motor mounted within each door
and the liftgate. The power lock motors for the doors
are integral to the door latch units. The liftgate
power lock motor is a separate unit secured to the
latch brainplate near the center of the liftgate and
operates the liftgate latch lock mechanism through a
connecting linkage rod.
The power lock motors for the four doors cannot be
adjusted or repaired and, if faulty or damaged, the
entire door latch unit must be replaced. The liftgate
power lock motor cannot be adjusted or repaired and,
if faulty or damaged, the entire liftgate latch actua-
tor (brainplate) unit must be replaced.
OPERATION
The driver side front door power lock motor is con-
trolled by the Driver Door Module (DDM). The
remaining power door lock motors and the liftgate
power lock motor are controlled by the Passenger
Door Module (PDM). A positive and negative battery
connection to the two motor terminals will cause the
power lock motor plunger to move in one direction.
Reversing the current through these same two con-
nections will cause the power lock motor plunger to
move in the opposite direction.
WJPOWER LOCKS 8N - 7
POWER LOCKS (Continued)

REMOTE KEYLESS ENTRY
MODULE
DESCRIPTION
The Remote Keyless Entry (RKE) receiver is a
radio frequency unit contained within the Passenger
Door Module (PDM). The PDM also contains the pro-
gram logic circuitry for the RKE system. The PDM is
secured with screws to the back of the trim panel
inside the passenger side front door. The RKE
receiver has a memory function to retain the vehicle
access codes of up to four RKE transmitters. The
receiver is designed to retain the transmitter codes in
memory, even if the battery is disconnected.
For diagnosis of the RKE receiver, the PDM, or the
Programmable Communications Interface (PCI) data
bus a DRBIIItscan tool and the appropriate diagnos-
tic information are required. The RKE receiver is
only serviced as a unit with the PDM and, if faulty
or damaged, the entire PDM unit must be replaced.
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/DOOR MODULE - DESCRIP-
TION).
OPERATION
The RKE receiver is energized by one of three mes-
sages from the RKE transmitter: Unlock, Lock, or
Panic. The PDM circuitry responds to these messages
to lock or unlock the power lock motors that it con-
trols. The PDM circuitry also sends Lock, Unlock,
and Panic messages to other electronic modules over
the Programmable Communications Interface (PCI)
data bus. These messages will result in the Driver
Door Module (DDM) locking or unlocking the driver
side front door, and the other electronic modules in
the vehicle responding as their programming dic-
tates.
REMOTE KEYLESS ENTRY
TRANSMITTER
DESCRIPTION
The Remote Keyless Entry (RKE) system Radio
Frequency (RF) transmitter is equipped with three
buttons, labeled Lock, Unlock, and Panic. It is also
equipped with a key ring and is designed to serve as
a key fob. The operating range of the transmitter
radio signal is up to 10 meters (30 feet) from the
RKE receiver.
Each RKE transmitter has a different vehicle
access code, which must be programmed into the
memory of the RKE receiver in the vehicle in order
to operate the RKE system. Two transmitters are
provided with the vehicle, but the RKE receiver canretain the access codes of up to four transmitters in
its memory. (Refer to 8 - ELECTRICAL/POWER
LOCKS/REMOTE KEYLESS ENTRY TRANSMIT-
TER - STANDARD PROCEDURE - RKE TRANS-
MITTER PROGRAMMING).
In addition, the RKE transmitters for vehicles
equipped with the optional Memory System are color-
coded and have a number ª1º or ª2º molded into the
transmitter case to coincide with the ªDriver 1
(Black)º and ªDriver 2 (Gray)º buttons of the memory
switch on the driver side front door trim panel. These
transmitters must also have their access codes pro-
grammed into the RKE receiver so that they coincide
with the ªDriver 1º and ªDriver 2º buttons of the
memory switch. (Refer to 8 - ELECTRICAL/POWER
SEATS - DESCRIPTION - MEMORY SYSTEM).
The RKE transmitter operates on two Panasonic
CR2016 (or equivalent) batteries. Typical battery life
is from one to two years. The RKE transmitter can-
not be repaired and, if faulty or damaged, it must be
replaced.
OPERATION
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the Remote Keyless Entry (RKE) transmitters.
DIAGNOSIS AND TESTING - REMOTE KEYLESS
ENTRY TRANSMITTER
(1) Replace the Remote Keyless Entry (RKE)
transmitter batteries. (Refer to 8 - ELECTRICAL/
POWER LOCKS/REMOTE KEYLESS ENTRY
TRANSMITTER - STANDARD PROCEDURE - RKE
TRANSMITTER BATTERIES). Test each of the RKE
transmitter functions. If OK, discard the faulty bat-
teries. If not OK, go to Step 2.
(2) Program the suspect RKE transmitter and
another known good transmitter into the RKE
receiver. Use a DRBIIItscan tool, as described in the
appropriate diagnostic information. (Refer to 8 -
ELECTRICAL/POWER LOCKS/REMOTE KEYLESS
ENTRY TRANSMITTER - STANDARD PROCE-
DURE - RKE TRANSMITTER PROGRAMMING).
(3) Test the RKE system operation with both
transmitters. If both transmitters fail to operate the
power lock system, use a DRBIIItscan tool and the
appropriate diagnostic information for further diag-
nosis of the RKE system. If the known good RKE
transmitter operates the power locks and the suspect
transmitter does not, replace the faulty RKE trans-
mitter.
NOTE: Be certain to perform the RKE Transmitter
Programming procedure again following this test.
This procedure will erase the access code of the
test transmitter from the RKE receiver.
WJPOWER LOCKS 8N - 9

STANDARD PROCEDURE
STANDARD PROCEDURE - RKE TRANSMITTER
PROGRAMMING
To program the Remote Keyless Entry (RKE)
transmitter access codes into the RKE receiver in the
Passenger Door Module (PDM) requires the use of a
DRBIIItscan tool. Refer to the appropriate diagnos-
tic information.
STANDARD PROCEDURE - RKE TRANSMITTER
BATTERIES
The Remote Keyless Entry (RKE) transmitter case
snaps open and shut for battery access. To replace
the RKE transmitter batteries:
(1) Using a trim stick or a thin coin, gently pry at
the notch in the center seam of the RKE transmitter
case halves near the key ring until the two halves
unsnap.
(2) Lift the back half of the transmitter case off of
the RKE transmitter.
(3) Remove the two batteries from the RKE trans-
mitter.(4) Replace the two batteries with new Panasonic
CR2016, or their equivalent. Be certain that the bat-
teries are installed with their polarity correctly ori-
ented.
(5) Align the two RKE transmitter case halves
with each other, and squeeze them firmly and evenly
together until they snap back into place.
NOTE: The RKE system for this model uses a roll-
ing code security strategy. This strategy requires
that synchronization be maintained between the
RKE transmitter and the RKE receiver. RKE trans-
mitter battery removal or replacement can cause a
loss of synchronization. If the RKE receiver fails to
respond to the RKE transmitter following battery
removal or replacement, depress and release the
RKE transmitter Unlock button repeatedly while lis-
tening carefully for the power door locks in the
vehicle to cycle. After between five and eight
presses of the Unlock button, the power door locks
should cycle, indicating that re-synchronization has
occurred.
8N - 10 POWER LOCKSWJ
REMOTE KEYLESS ENTRY TRANSMITTER (Continued)

POWER MIRRORS
TABLE OF CONTENTS
page page
POWER MIRRORS
DESCRIPTION.........................11
OPERATION...........................12
DIAGNOSIS AND TESTING - POWER
MIRRORS...........................12
AUTOMATIC DAY/NIGHT MIRROR
DESCRIPTION
DESCRIPTION - REAR VIEW MIRROR.....12
DESCRIPTION - OUTSIDE REAR VIEW
MIRROR............................13
OPERATION
OPERATION - REAR VIEW MIRROR.......13
OPERATION - OUTSIDE REAR VIEW
MIRROR............................13
DIAGNOSIS AND TESTING - AUTOMATIC DAY
/ NIGHT MIRROR......................13POWER FOLD-AWAY MIRROR - EXPORT
DESCRIPTION.........................14
OPERATION...........................14
DIAGNOSIS AND TESTING - POWER
FOLD-AWAY MIRROR - EXPORT..........14
REMOVAL.............................14
POWER MIRROR SWITCH
DESCRIPTION.........................15
OPERATION...........................15
SIDEVIEW MIRROR
DESCRIPTION.........................15
OPERATION...........................15
DIAGNOSIS AND TESTING - SIDEVIEW
MIRROR............................16
POWER MIRRORS
DESCRIPTION
Driver and passenger side power operated outside
rear view mirrors are standard factory-installed
equipment on this model. The power mirror system
allows the driver to adjust both outside mirrors elec-
trically from the driver seat position by operating a
switch on the driver side front door trim panel. The
power mirror system receives non-switched battery
current through a fuse in the Power Distribution
Center (PDC) so that the power mirrors remain oper-
ational, regardless of the ignition switch position.
The standard equipment power operated outside
rear view mirrors are also equipped with the heated
mirror system, which will only operate when the
ignition switch is in the On position and the rear
window defogger switch is turned on. When the rear
window defogger switch is in the On position, electric
heater grids on the rear window glass and behind
both outside rear view mirror glasses are energized.
These electric heater grids produce heat to help clear
the rear window glass and outside rear view mirrors
of ice, snow, or fog. (Refer to 8 - ELECTRICAL/
HEATED MIRRORS - DESCRIPTION) for more
information on this feature.
A driver side automatic dimming outside mirror
that dims the mirror to reduce the glare of bright
lights approaching the vehicle from behind, and a
memory system that automatically positions the
power mirrors for two different drivers are optionalfactory-installed equipment on this model. (Refer to 8
- ELECTRICAL/POWER MIRRORS/AUTOMATIC
DAY / NIGHT MIRROR - DESCRIPTION) for more
information. (Refer to 8 - ELECTRICAL/POWER
SEATS - DESCRIPTION) for more information.
This group covers the following components of the
power mirror system:
²Power mirrors
²Power mirror switch.
Certain functions and features of the power mirror
system rely upon resources shared with other elec-
tronic modules in the vehicle over the Programmable
Communications Interface (PCI) data bus network.
The PCI data bus network allows the sharing of sen-
sor information. This helps to reduce wire harness
complexity, internal controller hardware, and compo-
nent sensor current loads. At the same time, this sys-
tem 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
mirror 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-
WJPOWER MIRRORS 8N - 11

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)

(4) Turn the ignition switch to the Off position.
Check for continuity between the ground circuit cav-
ity of the overhead wire harness connector for the
automatic day/night mirror 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) Turn the ignition switch to the On position. Set
the parking brake. Place the transmission gear selec-
tor lever in the Reverse position. Check for battery
voltage at the backup lamp switch output circuit cav-
ity of the overhead wire harness connector for the
automatic day/night mirror. If OK, reconnect the
overhead wire harness connector to the automatic
day/night mirror connector receptacle and go to Step
6. If not OK, repair the open backup lamp switch
output circuit as required.
(6) Place the transmission gear selector lever in
the Neutral position. Place the automatic day/night
mirror switch in the Auto (LED next to the switch is
lighted) position (Fig. 1). Cover the forward facing
ambient photocell sensor to keep out any ambient
light.
NOTE: The ambient photocell sensor must be cov-
ered completely, so that no light reaches the sen-
sor. Use a finger pressed tightly against the sensor,
or cover the sensor completely with electrical tape.
(7) Shine a light into the rearward facing head-
lamp photocell sensor. The automatic day/night mir-
ror should darken. If OK, go to Step 8. If not OK,
replace the faulty automatic day/night mirror unit.
(8) With the mirror darkened, place the transmis-
sion gear selector lever in the Reverse position. The
automatic day/night mirror should return to its nor-
mal reflectance. If not OK, replace the faulty auto-
matic day/night mirror unit.POWER FOLD-AWAY MIRROR -
EXPORT
DESCRIPTION
Some vehicles are equipped with Power Fold-Away
Side View Mirrors. This feature allows both the
driver and passenger side view mirrors to fold
inward (retract) on demand. This feature is con-
trolled by an additional switch located on the power
mirror switch.
The fold-away side view mirror is attached to the
vehicle's door in the same manner as mirrors without
the fold-away option. The fold-away mirrors unique
option is the internal motor which allows the mirrors
to fold inward on demand. the fold-away mirror
motor is not serviceable separately, and if a motor is
found to be faulty the entire side view mirror must
be replaced.
OPERATION
When the mirror retract switch is depressed, both
of the side view mirrors will fold inward, thus mak-
ing the overall width of the vehicle the smallest pos-
sible. This can be very helpful where parking space is
an absolute minimum.
DIAGNOSIS AND TESTING - POWER
FOLD-AWAY MIRROR - EXPORT
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.
REMOVAL
The fold-away mirror motor is not serviceable sep-
arately, and if a motor is found to be faulty the entire
side view mirror must be replaced. (Refer to 8 -
ELECTRICAL/POWER MIRRORS/SIDEVIEW MIR-
ROR - REMOVAL).
Fig. 1 Automatic Day/Night Mirror
1 - LED INDICATOR
2 - SWITCH
3 - HEADLAMP SENSOR
8N - 14 POWER MIRRORSWJ
AUTOMATIC DAY/NIGHT MIRROR (Continued)

POWER MIRROR SWITCH
DESCRIPTION
Both the right and left power outside mirrors are
controlled by a single multi-function switch unit
located on the driver side front door trim panel. The
power mirror switch unit includes a three-position
rocker selector switch and four momentary direc-
tional push button switches.
The power mirror switch unit is integral to the
Driver Door Module (DDM). The power mirror switch
cannot be repaired or adjusted and, if faulty or dam-
aged, the entire DDM unit must be replaced. (Refer
to 8 - ELECTRICAL/ELECTRONIC CONTROL
MODULES/DRIVER DOOR MODULE - REMOVAL)
for the DDM service procedures.
OPERATION
The power mirror selector switch is moved right
(right mirror control), left (left mirror control), or
center to turn the power outside mirror system off.
When the selector switch is in the right mirror con-
trol or left mirror control position, one of the four
directional control buttons is depressed to control
movement of the selected mirror up, down, right, or
left. When the selector switch is in the Off position,
depressing any of the directional switches will not
change either mirror position.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the power mirror switches.
SIDEVIEW MIRROR
DESCRIPTION
Mechanically folding, power operated outside rear
view mirrors are standard equipment on this model.
Each power mirror housing contains two electric
motors, two drive mechanisms, an electric heating
grid, the mirror glass case and the mirror glass. One
motor and drive controls mirror up-and-down (verti-
cal) movement, and the other controls right-and-left
(horizontal) movement. If the vehicle is equipped
with the optional memory system, each mirror head
also contains two position potentiometers. One posi-
tion potentiometer monitors the vertical mirror
motor, and the other monitors the horizontal mirror
motor.
An optional driver side automatic dimming mirror
is able to automatically change its reflectance level.
This mirror is controlled by the circuitry of the auto-
matic day/night inside rear view mirror. A thin layer
of electrochromic material between two pieces of con-
ductive glass make up the face of the mirror. (Refer
to 8 - ELECTRICAL/POWER MIRRORS/AUTO-MATIC DAY / NIGHT MIRROR - DESCRIPTION) for
more information on this feature.
The power mirror unit cannot be repaired. Only
the mirror glass and glass case are serviced sepa-
rately. The replacement mirror glass is supplied with
an instruction sheet that details the recommended
replacement procedure. If any other component of the
power mirror unit is faulty or damaged, the entire
power mirror unit must be replaced.
OPERATION
Each of the two outside power mirrors includes two
reversible electric motors that are secured within the
power mirror housing. Each motor moves the mirror
case and glass through an integral drive unit. When
a power mirror motor is supplied with battery cur-
rent and ground, it moves the mirror case and glass
through its drive unit in one direction. When the bat-
tery current and ground feeds to the motor are
reversed, it moves the mirror case and glass in the
opposite direction.
The power mirrors are equipped with a standard
equipment electric heating grid that is applied to the
back of each outside rear view mirror glass. When an
electrical current is passed through the resistor wire
of the heating grid, it warms the mirror glass. (Refer
to 8 - ELECTRICAL/HEATED MIRRORS -
DESCRIPTION) for more information on the opera-
tion of the heated mirrors and the rear window
defogger system.
If the driver side mirror is equipped with the auto-
matic dimming outside mirror option, two photocell
sensors on the inside rear view mirror are used to
monitor light levels and adjust the reflectance of both
the inside and driver side outside mirrors. This
change in reflectance helps to reduce the glare of
headlamps approaching the vehicle from the rear.
(Refer to 8 - ELECTRICAL/POWER MIRRORS/AU-
TOMATIC DAY / NIGHT MIRROR - OPERATION)
for more information on this feature.
If the vehicle is equipped with the optional mem-
ory system, the Driver Door Module (DDM) and the
Passenger Door Module (PDM) store the mirror posi-
tion information as monitored through the mirror
motor position potentiometers. When the memory
system requests a recall of the stored mirror position,
the DDM and the PDM are able to duplicate the
stored mirror positions by moving the mirror motors
until the potentiometer readings match the stored
values.
WJPOWER MIRRORS 8N - 15