mirror controls JEEP GRAND CHEROKEE 2002 WJ / 2.G Workshop Manual

Frequency (RF) Remote Keyless Entry (RKE)
receiver. The DDM and PDM control and integrate
many functions and features of the vehicle through
both hard wired outputs and messages over the PCI
data bus. The functions and features that the door
modules support or control include the following:
²Automatic Door Lock- The two door modules
provide an automatic door lock feature which locks
the doors when the vehicle is moving. This is a pro-
grammable feature.
²Automatic Door Unlock On Exit- The two
door modules provide an automatic door unlock on
exit feature. This feature will unlock all the doors if
they were locked via the automatic door lock feature
after the vehicle has stopped moving and the driver
door is opened. This is a programmable feature via
the EVIC.
²Customer Programmable Features- Each
door module provides support for certain customer
programmable features that are monitored on the
PCI bus.
²Cylinder Lock Switch Status- The DDM
monitors and transmits the status of the cylinder
lock switch on the driver side front door lock cylin-
der.
²Door Courtesy Lamp Control- Each door
module provides control of its own optional front
door-mounted courtesy lamp.
²Door Lock Inhibit- Each door module pro-
vides a door lock inhibit feature which prevents the
doors from being locked with a power lock switch ifthe key was left in the ignition and a front door is
open.
²Express-Down Window- The DDM provides
an express-down feature for the driver side front door
window only.
²Extended Window Operation- Both door
modules provide an extended power window opera-
tion feature that allows operation of the power win-
dows for 45 seconds following ignition Off or until a
front door is opened.
²Front Door Ajar Switch Status- Each door
module monitors and transmits the status of its own
front door ajar switch.
²Heated Mirrors- Each door module provides
control for its own optional heated outside rear view
mirror.
²Illuminated Entry- Each door module sup-
ports an illuminated entry feature through its own
optional front door-mounted courtesy lamp.
²Memory Mirrors- Each door module provides
control for its own optional memory outside rear view
mirror.
²Memory Switch- The DDM monitors the sta-
tus of the optional memory switch and controls the
illumination of the memory switch ªsetº Light Emit-
ting Diode (LED) indicator and illumination lamps.
²Memory System- The DDM transmits memory
set and recall messages based upon inputs from the
memory switch. If the optional RKE linked to mem-
ory feature is enabled, the DDM will also transmit
memory recall messages based upon memory
requests received from the Remote Keyless Entry
(RKE) system in the PDM. Certain memory system
features are programmable.
²Power Foldaway Mirrors - Export Only-
Each door module provides support for the optional
power foldaway outside mirrors. The DDM also
houses the control switch for this system.
²Power Lock Control- The DDM provides con-
trol for the driver side front door power lock motor,
while the PDM provides control for the power lock
motors of the three remaining doors and the liftgate.
²Power Lock Switch Status- Each door mod-
ule monitors and transmits the status of its own inte-
gral power lock switch.
²Power Window Control- Each door module
provides control for both the front and rear door
power window motors and the rear door power win-
dow switches on the same side of the vehicle.
²Power Window Switch Status- The DDM
monitors and transmits the status of its integral pas-
senger side front and rear power window switches.
²Remote Keyless Entry- The PDM monitors
and transmits the status of the Remote Keyless
Entry (RKE) system and provides support for the
RKE Lock (with the optional horn chirp and park
Fig. 7 Door Module
1 - FRONT DOOR TRIM PANEL
2 - SCREW (5)
3 - DOOR MODULE
8E - 8 ELECTRONIC CONTROL MODULESWJ
DOOR MODULE (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)

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

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)