ECU CHRYSLER CARAVAN 2002 Owners Manual

DOOR LOCK CIRCUIT PROTECTION
The BCM controls the door lock output drivers. If
the door lock switch is actuated continuously for
more than one second the BCM will turn the output
driver OFF (the BCM would consider the switch
stuck). The lock motors are protected with Positive
Temperature Coefficient (PTC) device that prevents
motor burn out.
REMOTE KEYLESS ENTRY SYSTEM
²LOCK: Pressing the LOCK button locks all
doors and sounds horn (chirp) and arm the Vehicle
Theft Security System, if equipped. The chirp verifies
that the RKE receiver has sent a message to the
BCM for door lock operation. If a door has not been
closed before pressing the LOCK button, the vehicle
may not be secured and the VTSS will not arm until
the door is closed.
²UNLOCK: Pressing the UNLOCK button once
will unlock the driver's side doors and activate the
illuminated entry system and disarm Vehicle Theft
Security System, if equipped. Pressing the UNLOCK
button twice within five seconds will unlock all doors
and activate the illuminated entry system.
²LEFT SLIDING DOOR: Pressing the LEFT
SLIDING DOOR BUTTON opens/closes the left
power sliding door remotely.
²RIGHT SLIDING DOOR: Pressing the RIGHT
SLIDING DOOR BUTTON opens/closes the right
power sliding door remotely.
²LIFTGATE:
Pressing the LIFTGATE BUTTON
opens/closes the liftgate remotely, if equipped.If not
equipped with power liftgate, pressing the liftgate but-
ton will allow a one time 30 second access to liftgate.
²PANIC: Pressing the PANIC button sounds the
horns at half second intervals, flashes the exterior
lamps, and turns ON the interior lamps. The panic
alarm will remain on for three minutes, or until the
PANIC button is actuated again or the ignition
switch is turned to the RUN position.
The Remote Keyless Entry Module is capable of
retaining the transmitter Vehicle Access Code(s)
(VAC) in its memory even after vehicle power has
been interrupted.
NOTE: Additional features available to the customer
are described in the Vehicle Owners Manual.
The RKE system activates the optional memory
seat, mirror system and adjustable pedals, if
equipped. Two primary key fob transmitters can be
programmed to actuate memory seat and mirror set-
ting 1 or 2. Two additional key fob transmitters can be
added, but they will not be able to operate the mem-
ory seat and mirror system (Refer to 8 - ELECTRI-
CAL/POWER SEATS - OPERATION) and (Refer to 8 -
ELECTRICAL/POWER MIRRORS - OPERATION).
DOOR CYLINDER LOCK
SWITCH
DESCRIPTION
The Door Cylinder Lock Switch is used to:
²Unlock/Lock all the doors via the Central Lock-
ing feature.
²Arm/Disarm the Vehicle Theft Security System.
²Trigger the Illuminated Entry feature.
The door cylinder lock switch is mounted to the
rear of the driver and passenger door lock cylinders.
When installed on the rear of the cylinder, there is a
tab on the lock cylinder that aligns with the switch
to prevent it from turning. An anti-rotating device.
The door cylinder lock switch is a one time use
switch. Once it is removed from the rear of the door
lock cylinder, it may not be reinstalled and a new
switch must be used.
OPERATION
When the Door Cylinder Lock Switch is turned
either way using the door key cylinder, the BCM
reads a direct message signal from the switch, via
the Programmable Communication Interface (PCI)
bus.
If turning the key cylinder once, toward the front
of the vehicle (for either driver or passenger doors),
this will:
(1) Mechanically unlock the door lock.
(2) Disarm the Vehicle Theft Security System (if
equipped).
(3) Turn on the Illuminated Entry (if equipped) for
approximately 30 seconds.
If the key cylinder is turned to the unlock position
(toward the front of vehicle) twice within two sec-
onds, all the doors and liftgate will unlock (if
equipped with the central locking feature).
To lock the vehicle using the door cylinder lock
switch, turn the key cylinder toward the rear of the
vehicle (either passenger or driver doors) once. This
will lock the door that you are using the key on. If
equipped with the central locking feature, this will
lock all the other doors and liftgate. Furthermore,
this will arm the vehicle theft security system and
turn off the illuminated entry.
DIAGNOSIS AND TESTING - DOOR CYLINDER
LOCK SWITCH
(1) Visually inspect the switch for proper installa-
tion. Make sure it is seated on the rear of the key
cylinder, with the tab of the door key cylinder prop-
erly aligned with the slot on the door cylinder lock
switch.
(2) Disconnect the switch at the harness connector
and check the resistance in each switch position.
RSPOWER LOCKS8N-41
POWER LOCKS (Continued)
ProCarManuals.com

REMOTE KEYLESS ENTRY
MODULE
DESCRIPTION
The RKE module is capable of retaining up to four
different Vehicle Access Codes.
OPERATION
Whenever the vehicle battery power is interrupted
the RKE Module will retain all vehicle access codes
in its memory. When replacing or adding a key fob
transmitter (maximum 4) a DRB IIItscan tool is
required to program the RKE Module to accept the
new Vehicle Access Code if a customer owned trans-
mitter is not available. Refer to Electrical, Remote
Keyless Entry Module, Standard Procedure - Pro-
gramming RKE Module or the Proper Body Diagnos-
tic Procedures manual.
DIAGNOSIS AND TESTING - REMOTE KEYLESS
ENTRY MODULE
Refer to the appropriate wiring information. The
wiring information 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 har-
ness connectors, splices and grounds. Refer to the
proper Body Diagnostic Procedures Manual for test-
ing the Remote Keyless Entry system using a DRB
IIItscan tool. Also refer to other interrelated sys-
tems groups within this manual:
²Vehicle Theft Security System
²Power Seats
²Power Mirrors
STANDARD PROCEDURE - PROGRAMMING
RKE MODULE
(1) Using a functional key fob transmitter, unlock
the vehicle and disarm the Vehicle Theft Security
System.
(2) Insert ignition key into the ignition switch.
(3) Turn the ignition switch to RUN position with-
out starting engine.
(4) Using a functional key fob transmitter, press
and hold the UNLOCK button for a minimum five
seconds (maximum ten seconds).
(5) While still holding UNLOCK button, and
before ten seconds passes, press the PANIC button
and release both at the same time. A single chime
will sound to verify that the RKE module is set to
receive the new Vehicle Access Code(s).
(6) Within 30 seconds of the chime, press and
release the ªLOCKº and ªUNLOCKº buttons on the
transmitter at the same time. Then press and release
any one of the buttons. The BCM will sound anabbreviated chime to acknowledge that the program-
ming of the transmitter has been completed and was
successful.
(7) Repeat step 6 for all transmitters that will be
used with this vehicle (up to 4 total).
(8) Programming mode will last for 30 seconds. To
get out of programming mode sooner, turn the igni-
tion OFF. A single chime will sound to verify that the
RKE module will no longer accept additional Vehicle
Access Code(s).
(9) When Vehicle Access Code(s) programming is
complete, turn the ignition switch to the OFF posi-
tion and verify RKE system operation using each key
fob.
NOTE:
Only the two key fob transmitters that have been
programmed to the memory seat and mirror system
will operate it. If any key fob is replaced, the mem-
ory seat and mirror module will require program-
ming. (Refer to 8 - ELECTRICAL/POWER SEATS -
DIAGNOSIS AND TESTING).
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove instrument panel top cover (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL TOP PAD - REMOVAL).
(3) Remove screws holding RKE module to instru-
ment panel.
(4) Disconnect wire connector from RKE module
(Fig. 4).
(5) Remove the RKE module from vehicle.
Fig. 4 RKE MODULE
1 - REMOTE KEYLESS ENTRY MODULE
2 - INSTRUMENT PANEL
3 - DEMISTER DUCT
8N - 44 POWER LOCKSRS
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²Body Control Module (BCM)- Refer toBody
Control Modulein Electronic Control Modules for
more information.
²Powertrain Control Module (PCM)- Refer to
Powertrain Control Modulein Electronic Control
Modules for more information.
Refer toHeated Seat Systemfor more informa-
tion on the heated seat system. Refer toRemote
Keyless Entry Systemin Power Lock Systems for
more information on the RKE system.
Refer toWiring Diagramsfor complete circuit
diagrams. Following are descriptions, theory of oper-
ation, diagnosis/testing procedures and removal/in-
stallation procedures of the major components in the
memory and power seat systems.
OPERATION
OPERATION - POWER SEAT SYSTEM
The power seat system receives battery current
through fuse #22 in the Intelligent Power Module
and a circuit breaker under the front seats, regard-
less of the ignition switch position.
When a power seat switch control knob or knobs
are actuated, a battery feed and a ground path are
applied through the switch contacts to the appropri-
ate power seat track adjuster motor. The selected
adjuster motor operates to move the seat track
through its drive unit in the selected direction until
the switch is released, or until the travel limit of the
seat track 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 seat track has reached its travel
limit. The power seat track each contain a self-reset-
ting circuit breaker to protect them from overload.
However, consecutive or frequent resetting of the cir-
cuit breaker must not be allowed to continue, or the
motor may be damaged. Refer to the owner's manual
in the vehicle glove box for more information on the
features, use and operation of the power seat system.
OPERATION - MEMORY SYSTEM
The memory system receives battery current
through fuse #22 in the Intelligent Power Module
and the power seat system circuit breaker, located
under each front seat near the rear edge of the seat
cushion pans. The Memory Seat Mirror Module
(MSMM) will drive a maximum of 2 motors at a time
in a given direction. If conflicting directions are
requested, the priority for response will be as follows:
²Seat Track Rearward or Forward²Seat Front Down or Up
²Seat Rear Down or Up
²Recliner Rearward or Forward
The inputs from these switches to the MSMM is a
current limited battery source fed by the MSMM.
This protects the MSMM printed circuit board traces
from acting as fuses. All of these switch contact
inputs to the MSMM are normally closed to ground,
except when actuated.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the memory system. For diagnosis of the MSMM,
the PCI data bus, or the other electronic modules on
the PCI data bus that provide inputs and outputs for
the memory system, the use of a DRBIIItscan tool
and the proper Diagnostic Procedures manual are
recommended.
ELECTRONIC VEHICLE INFORMATION CENTER
The Electronic Vehicle Information Center (EVIC)
serves as the user interface for the memory system.
It displays memory system status messages and pro-
vides the user with the means for enabling and dis-
abling the many customer programmable features
available on the vehicle, including those for the mem-
ory system.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the EVIC. Refer toElectronic Vehicle Informa-
tion Centerin Overhead Console Systems for more
information on the EVIC.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - POWER SEAT
SYSTEM
Following are tests that will help to diagnose the
hard wired components and circuits of the power seat
system. However, if the vehicle is also equipped with
the optional memory system, these tests may not
prove conclusive in the diagnosis of the driver side
power seat. In order to obtain conclusive testing of
the driver side power seat with the memory system
option, the Programmable Communications Interface
(PCI) data bus network and all of the electronic mod-
ules that provide inputs to, or receive outputs from
the memory system components must be checked.
The most reliable, efficient, and accurate means to
diagnose the driver side power seat with the memory
system option requires the use of a DRB IIItscan
tool and the proper Diagnostic Procedures manual.
The DRB IIItscan tool can provide confirmation that
the PCI data bus is functional, that all of the elec-
tronic modules are sending and receiving the proper
messages on the PCI data bus, and that the memory
RSPOWER SEAT SYSTEM8N-53
POWER SEAT SYSTEM (Continued)
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The switch is secured to the back of the seat cush-
ion side shield with two screws. However, the control
knobs for the seat switch unit must be removed
before the seat switch can be removed from the side
shield.
The power seat switch cannot be repaired. If one
switch is damaged or faulty, the entire power seat
switch unit must be replaced.
OPERATION
When a power seat 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. See the owner's
manual in the vehicle glove box for more information
on the power seat switch functions and the seat
adjusting procedures.
DIAGNOSIS AND TESTING - DRIVER SEAT
SWITCH
(1) Remove the power seat switch, refer to the
Switch Removal and Installation procedures in this
section.
(2) Using an ohmmeter, check pin #1 of the power
seat switch connector for continuity to ground. It
should be present, If OK go to Step3,IfNOTOK
repair the open ground circuit as required.
(3) Using an voltmeter, check pin #5 of the power
seat switch connector for approx. 12v. It should be
present, If OK go to Step4,IfNOTOKrepair the
open voltage supply circuit as required.
(4) Using an ohmmeter, verify the Seat Switch
Continuity Test table, using the seat switch connec-
tor (Fig. 3). If there is no continuity at any of the
switch positions, replace the power seat switch.
DRIVER SEAT SWITCH CONTINUITY TEST
TABLE
SWITCH
POSITIONCONTINUITY BETWEEN
PINS
DRIVER
OFF PIN5&4
PIN5&3
PIN5&2
PIN5&10
PIN5&9
PIN5&8
PIN5&7
PIN5&6
FRONT RISER
UPPIN5&6
PIN1&9
FRONT RISER
DOWNPIN5&9
PIN1&6
CENTER
SWITCH
FORWARDPIN5&3
PIN1&10
CENTER
SWITCH
REARWARDPIN5&10
PIN3&1
REAR RISER UP PIN5&7
PIN1&8
REAR RISER
DOWNPIN5&8
PIN1&7
RECLINER UP PIN5&2
PIN4&1
RECLINER
DOWNPIN5&4
PIN2&1
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) On models equipped with the eight-way power
seat, using a push pin remover or another suitable
wide flat-bladed tool, gently pry the power seat and
power recliner switch knobs off of the switch levers
(Fig. 4).
Fig. 3 Seat Switch Pin Call-Out
RSPOWER SEAT SYSTEM8N-55
DRIVER SEAT SWITCH (Continued)
ProCarManuals.com

(3) Remove the screws that secure the outboard
seat cushion side shield to the seat cushion frame.
Refer to the Body section of the service manual for
the procedure.
(4) Pull the outboard seat cushion side shield away
from the seat cushion frame far enough to access the
power seat switch wire harness connector.
(5) Disconnect the power seat wire harness connec-
tor from the power seat switch connector receptacle.
(6) Remove the screws that secure the power seat
switch to the inside of the outboard seat cushion side
shield.
(7) Remove the power seat switch from the out-
board seat cushion side shield.
INSTALLATION
(1) Position the power seat switch onto the out-
board seat cushion side shield.
(2) Install and tighten the screws that secure the
power seat switch to the inside of the outboard 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 seat switch connector receptacle.
(4) Position the outboard seat cushion side shield
onto the seat cushion frame
(5) Install and tighten the 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) Install the switch knobs on the switch control
levers, if equipped.
(7) Reconnect the battery negative cable.
MEMORY SET SWITCH
DESCRIPTION
Vehicles equipped with the memory system have a
memory switch mounted to the driver side front door
trim panel (Fig. 5). 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 Body Control Module
(BCM). The BCM 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 Dia-
grams.
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
(LED) for visibility. When the memory set switch is
depressed, a resistance value is sent to the Body
Control Module via hard wired connections. When
the memory system is in ªsetº mode a chime will be
generated by the body control module.
Fig. 4 Removing Switch Control Knobs - Typical
Fig. 5 Memory Switch Location
1 - Memory Switch
2 - Switch Bezel
8N - 56 POWER SEAT SYSTEMRS
DRIVER SEAT SWITCH (Continued)
ProCarManuals.com

See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of the memory switch.
DIAGNOSIS AND TESTING - MEMORY SWITCH
(1) Remove the memory set switch from the driv-
ers door panel (Refer to 8 - ELECTRICAL/POWER
SEATS/MEMORY SET SWITCH - REMOVAL).
(2) Using an ohmmeter, check for continuity on the
memory select switch MUX circuit between the body
control module C2 electrical connector and the mem-
ory switch connector. Continuity should be present, If
OK go to Step 3, If NOT OK repair the open or
shorted MUX circuit as required.
(3) Using an ohmmeter, check for continuity on the
memory select switch RETURN circuit between the
body control module C2 electrical connector and the
memory switch connector. Continuity should be
present, If OK go to Step 4, If NOT OK repair the
open or shorted RETURN circuit as required.
(4) Using an ohmmeter, test the resistances of the
memory switch in each switch position. See the Mem-
ory Switch Test Table. If OK, refer toDiagnosis and
Testing Memory Systemin this section. If not OK,
replace the faulty memory set switch.
MEMORY SWITCH TEST TABLE
MEMORY
SWITCH
POSITIONRESISTANCE
BETWEEN
PINSRESISTANCE
RANGE
(OHMS)
NEUTRAL 1&2 24650   5%
(24.65 k)
MEMORY 1 1&2 6850   5%
(6.85 k)
MEMORY 2 1&2 2100   5%
(2.10 k)
SET 1&2 4490   5%
(4.49 k)
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the front door trim panel switch bezel
from the driver side front door. Using a thin flat-
bladed pry tool, gently pry the switch bezel away
from the drivers door trim panel.
(3) Disconnect the memory switch wire harness
connector from the memory switch.
(4) Remove the two screws that secure the memory
switch to the back of the driver side front door trim
panel switch bezel.
(5) Remove the memory switch.
INSTALLATION
(1) Position the memory switch and install and
tighten the two screws that secure the memory
switch to the back of the driver side front door trim
panel switch bezel. Tighten the screws to 2.2 N´m (20
in. lbs.).
(2) Reconnect the memory switch wire harness
connector to the memory switch.
(3) Install the trim panel switch bezel onto the
driver side front door.
(4) Reconnect the battery negative cable.
PASSENGER SEAT SWITCH
DESCRIPTION
Vehicles equipped with power seats utilize a ten-
way power seat switch. This ten-way power seat
switch features two knobs ganged together on the
outboard seat cushion side shield.
The switch is secured to the back of the seat cush-
ion side shield with two screws. However, the control
knobs for the seat switch unit must be removed
before the seat switch can be removed from the side
shield.
The power seat switch cannot be repaired. If one
switch is damaged or faulty, the entire power seat
switch unit must be replaced.
OPERATION
When a power seat 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. See the owner's
manual in the vehicle glove box for more information
on the power seat switch functions and the seat
adjusting procedures.
RSPOWER SEAT SYSTEM8N-57
MEMORY SET SWITCH (Continued)
ProCarManuals.com

DIAGNOSIS AND TESTING - PASSENGER SEAT
SWITCH
(1) Remove the power seat switch, refer to the
Switch Removal and Installation procedures in this
section.
(2) Using an ohmmeter, check pin #1 of the power
seat switch connector for continuity to ground. It
should be present, If OK go to Step3,IfNOTOK
repair the open ground circuit as required.
(3) Using an voltmeter, check pin #5 of the power
seat switch connector for approx. 12v. It should be
present, If OK go to Step4,IfNOTOKrepair the
open voltage supply circuit as required.
(4) Using an ohmmeter, perform the Seat Switch
Continuity Test table using (Fig. 6). If there is no
continuity at any of the switch positions, replace the
power seat switch.
PASSENGER SEAT SWITCH CONTINUITY
TEST TABLE
SWITCH
POSITIONCONTINUITY BETWEEN
PINS
PASSENGER
OFF PIN5&4
PIN5&3
PIN5&2
PIN5&10
PIN5&9
PIN5&8
PIN5&7
PIN5&6
FRONT RISER
UPPIN5&9
PIN1&6
FRONT RISER
DOWNPIN5&6
PIN1&9
CENTER
SWITCH
FORWARDPIN5&3
PIN1&10
CENTER
SWITCH
REARWARDPIN5&10
PIN3&1
REAR RISER UP PIN5&8
PIN1&7
REAR RISER
DOWNPIN5&7
PIN1&8
RECLINER UP PIN5&2
PIN4&1
RECLINER
DOWNPIN5&4
PIN2&1
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) On models equipped with the eight-way power
seat, using a push pin remover or another suitable
wide flat-bladed tool, gently pry the power seat and
power recliner switch knobs off of the switch levers
(Fig. 7).
(3) Remove the screws that secure the outboard
seat cushion side shield to the seat cushion frame.
Refer to the Body section of the service manual for
the procedure.
(4) Pull the outboard seat cushion side shield away
from the seat cushion frame far enough to access the
power seat switch wire harness connector.
(5) Disconnect the power seat wire harness connec-
tor from the power seat switch connector receptacle.
(6) Remove the screws that secure the power seat
switch to the inside of the outboard seat cushion side
shield.
Fig. 6 Seat Switch Pin Call-Out
Fig. 7 Removing Switch Control Knobs - Typical
8N - 58 POWER SEAT SYSTEMRS
PASSENGER SEAT SWITCH (Continued)
ProCarManuals.com

(7) Remove the power seat switch from the out-
board seat cushion side shield.
INSTALLATION
(1) Position the power seat switch onto the out-
board seat cushion side shield.
(2) Install and tighten the screws that secure the
power seat switch to the inside of the outboard 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 seat switch connector receptacle.
(4) Position the outboard seat cushion side shield
onto the seat cushion frame
(5) Install and tighten the 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) Install the switch knobs on the switch control
levers, if equipped.
(7) Reconnect the battery negative cable.
MEMORY MIRROR/SEAT
MODULE
DESCRIPTION
Vehicles equipped with the memory mirror/seat
option, utilize a memory module located under the
drivers front seat. This module is basically wired in-
line between the power seat switch and the power
seat track/adjuster motors, or in-line between the
power mirror switch and the power side view mirror.
The MSMM contains a central processing unit that
communicates with other modules on the Program-
mable Communications Interface (PCI) data bus net-
work.
The Memory Seat/Mirror Module (MSMM) receives
hard wired inputs from the driver power seat switch
and the potentiometers on each of the driver side
power seat track motors, or from the power mirror
switch and the potentiometers on the side view mir-
ror. The MSMM receives messages over the PCI data
bus from the Body Control Module (BCM) (memory
switch status), the Powertrain Control Module (PCM)
(vehicle speed status). The MSMM will prevent the
seat memory recall function from being initiated if
the driver side seat belt is buckled, if the transmis-
sion gear selector lever is not in the Park or Neutral
positions, or if the vehicle is moving.
For diagnosis of the MSMM or the PCI data bus, a
DRBIIItscan tool and the proper Diagnostic Proce-
dures manual are recommended. The MSMM cannot
be repaired and, if faulty or damaged, it must be
replaced. Refer toMemory Systemin the Power
Seat or Power Mirror section of this manual for more
information on the memory system option.
OPERATION
When memory system operation is requested
(depressing of the memory switch), a resistor multi-
plexed signal is sent from the memory switch to the
body control module (BCM). The body control module
will then send the appropriate signals out to the
memory/mirror seat module, the memory/mirror seat
module then applies the voltage supply to the power
seat track or side-view mirror if the proper require-
ments are met. The vehicle speed must equal zero
and the transmission must be in park or neutral in
order for the memory system to function.
DIAGNOSIS AND TESTING - MEMORY
MIRROR/SEAT MODULE
Visually inspect the related wiring harness connec-
tors. Look for broken, bent, pushed out, or corroded
terminals. If any of the above conditions are present,
repair as necessary. If not, use a DRB IIItscan tool
and the proper Diagnostic Procedures Manual to test
the memory/mirror seat module. For complete circuit
diagrams, refer toWiring Diagrams.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the driver side front bucket seat
retaining nuts from under the vehicle (Refer to 23 -
BODY/SEATS/SEAT - REMOVAL).
(3) Lift the drivers seat up and out of the mount-
ing holes in the floor pan and lay the seat rearward
to access the module located under the seat. It is not
necessary to disconnect the seat electrical, just use
care not to damage the wiring by over-extending.
(4) Disconnect the memory/mirror seat module
electrical connectors. Depress the retaining tab and
pull straight apart.
(5) Remove the module retaining bolts and remove
the module from the bracket.
INSTALLATION
(1) Position and install the module retaining bolts.
(2) Connect the memory/mirror seat module elec-
trical connectors.
(3) Position the drivers seat in the mounting holes
in the floor pan.
(4) Install the driver side front bucket seat retain-
ing nuts from under the vehicle (Refer to 23 - BODY/
SEATS/SEAT - INSTALLATION).
(5) Connect the battery negative cable.
RSPOWER SEAT SYSTEM8N-59
PASSENGER SEAT SWITCH (Continued)
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DRIVER POWER SEAT TRACK
DESCRIPTION
The eight-way power seat option includes a electri-
cally operated power seat track located under each
front seat. The left side power seat track also pro-
vides the mounting location for the body control mod-
ule on this vehicle. The power seat circuit breakers
are mounted on the rear of each power seat track,
just behind the seat rear trim panel. The lower half
of the power seat track is secured to the floor panel
via four studs and nuts that must be accessed from
the underside of the vehicle. Four bolts secure the
bottom of the seat cushion pan to the upper half of
the power seat track unit. Four additional bolts
secure the seat back frame to the power seat track
unit.
The power seat track unit includes four 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 four power seat
track motors used on models equipped with the
optional memory system incorporates a position
potentiometer integral to the motor assembly, which
electronically monitors the motor position. This
enables the memory system to function by referenc-
ing the motor positions programmed into the memory
seat/mirror module.
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. A third motor is
the horizontal adjustment motor, which moves the
seat track in the forward and rearward directions.
The forth motor is the recliner adjustment motor,
which moves the seat back in the forward and rear-
ward directions.
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.
OPERATION
When a power seat 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 andground 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.
See the owner's manual in the vehicle glove box for
more information on the power seat switch functions
and the seat adjusting procedures.
DIAGNOSIS AND TESTING - DRIVER POWER
SEAT TRACK
WARNING: SOME VEHICLES ARE EQUIPPED WITH
SEATBACK MOUNTED AIRBAGS. BEFORE
ATTEMPTING TO DIAGNOSE OR SERVICE ANY
SEAT OR POWER SEAT SYSTEM COMPONENT
YOU MUST FIRST DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE CABLE. THEN WAIT TWO MIN-
UTES FOR THE SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE FURTHER SYSTEM SERVICE.
THIS IS THE ONLY SURE WAY TO DISABLE THE
AIRBAG SYSTEM. FAILURE TO DO SO COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
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
Diagnosis and Testing Power Seat Switchin this
section. 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.
TESTING POWER SEAT TRACK MOTORS
(1) Check the power seat circuit breaker under the
seat. 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 under the seat. If OK, go to Step 3. If
not OK, repair the open fused B(+) circuit to the fuse
in the Intelligent Power Module 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-
8N - 60 POWER SEAT SYSTEMRS
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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 under the seat 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 toDiagnosis
and Testing Power Seat Switchin this section. 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.
REMOVAL
WARNING: SOME VEHICLES ARE EQUIPPED WITH
SEATBACK MOUNTED AIRBAGS. BEFORE
ATTEMPTING TO DIAGNOSE OR SERVICE ANY
SEAT OR POWER SEAT SYSTEM COMPONENT
YOU MUST FIRST DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE CABLE. THEN WAIT TWO MIN-
UTES FOR THE SYSTEM CAPACITOR TO DIS-
CHARGE BEFORE FURTHER SYSTEM SERVICE.
THIS IS THE ONLY SURE WAY TO DISABLE THE
AIRBAG SYSTEM. FAILURE TO DO SO COULD
RESULT IN ACCIDENTAL AIRBAG DEPLOYMENT
AND POSSIBLE PERSONAL INJURY.
(1) Remove the appropriate seat from the vehicle
and place it on a clean work surface(Refer to 23 -
BODY/SEATS/SEAT - REMOVAL).
(2) Remove the Body Control Module retaining
screws.
(3) Disconnect the body control module electrical
connectors and remove the body control module from
the power seat track.
(4) Remove the rear fabric blocker trim panel from
the rear of the front seat.
(5) Remove the seat side cover and power seat
switch as an assembly (Refer to 23 - BODY/SEATS/
SEAT CUSHION SIDE COVERS - REMOVAL).
(6) Disconnect all electrical connectors connecting
the power seat track to the seat assembly.
(7) Pull the seat back trim cover up slightly to
access and remove the two seat back frame mounting
bolts and also remove two seat back recliner bolts.
(8) Remove four seat track mounting bolts from
the seat cushion pan.
(9) Remove the power seat track from the seat.
INSTALLATION
(1) Position the seat cushion on the seat track.
(2) Install the four seat track retaining bolts in the
seat cushion pan. Torque the bolts to 28.5 N´m.
(3) Position the seat back and install the two seat
back frame mounting bolts and the two seat back
recliner bolts. Torque the bolts to 55 N´m.
(4) Route and connect the electrical connectors
between the power seat track and the seat assembly.
(5) Install the seat side cover and power seat
switch as an assembly (Refer to 23 - BODY/SEATS/
SEAT CUSHION SIDE COVERS - INSTALLATION).
(6) Install the rear fabric blocker trim panel on the
rear of the front seat.
(7) Position the body control module and connect
the body control module electrical connectors.
(8) Install the Body Control Module retaining
screws.
(9) Install the seat assembly in the vehicle (Refer
to 23 - BODY/SEATS/SEAT - INSTALLATION).
PASSENGER POWER SEAT
TRACK
DESCRIPTION
The eight-way power seat option includes a electri-
cally operated power seat track unit located under
each front seat. The power seat circuit breaker is
mounted on the rear of the power seat track, just
behind the seat rear trim panel. The lower half of the
power seat track is secured to the floor panel via four
studs and nuts that must be accessed from the
underside of the vehicle. Four bolts secure the bot-
tom of the seat cushion frame to the upper half of the
power seat track unit. Four additional bolts secure
the seat back frame to the power seat track unit.
The power seat track unit includes four 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.
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. A third motor is
the horizontal adjustment motor, which moves the
seat track in the forward and rearward directions.
The forth motor is the recliner adjustment motor,
which moves the seat back in the forward and rear-
ward directions.
RSPOWER SEAT SYSTEM8N-61
DRIVER POWER SEAT TRACK (Continued)
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