2002 JEEP LIBERTY Electronic control modules

mounted to the back of the quarter panel on each
side of the tailgate at the rear of the vehicle. The
park lamps include a license plate lamp or lamps,
depending upon the requirements of the market for
which the vehicle is manufactured. Vehicles with a
license plate tub located near the left end of the rear
bumper fascia have a single lamp, while vehicles
with a license plate module located on the spare tire
carrier have two license plate lamps. In certain mar-
kets where required, a front position lamp that is
integral to each headlamp unit is illuminated instead
of the front park lamps and front side marker lamps
in the park lamps circuit; and, a rectangular, red
reflector is located on the rear bumper fascia just
inboard and below each rear lamp unit.
²Rear Fog Lamps- Rear fog lamps are avail-
able only in certain markets where they are required
equipment. The rear fog lamps are integral to the
rear lamp units mounted to the back of the quarter
panel on each side of the tailgate at the rear of the
vehicle.
²Turn Signal Lamps- The turn signal lamps
include the front turn signal and front side marker
lamps that are integral to the front lamp units
mounted at each end of the bumper fascia at the
front of the vehicle, as well as rear turn signal lamps
that are integral to the rear lamp units mounted to
the back of the quarter panel on each side of the tail-
gate at the rear of the vehicle. In certain markets
where required, a repeater lamp unit mounted to
each front fender just behind the front wheel opening
is illuminated instead of the front side marker lamp
in each turn signal lamp circuit.
Other components of the exterior lighting system
for this model include:
²Combination Flasher- An electronic combina-
tion flasher is integral to the hazard warning switch
in the center of the instrument panel.
²Backup Lamp Switch- Vehicles equipped with
a manual transmission have a plunger-type backup
lamp switch located on the transmission housing. A
Transmission Range Sensor (TRS) integral to the
solenoid pack on the valve body of the optional elec-
tronic automatic transmission performs the backup
lamp switch function on models that are so equipped.
²Brake Lamp Switch- A plunger-type brake
lamp switch is located on the steering column sup-
port bracket under the instrument panel and actu-
ated by the brake pedal arm.²Body Control Module- The Body Control
Module (BCM) is located on the Junction Block (JB)
under the driver side outboard end of the instrument
panel. (Refer to 8 - ELECTRICAL/ELECTRONIC
CONTROL MODULES/BODY CONTROL MODULE
- DESCRIPTION).
²Daytime Running Lamp Relay- Vehicles
manufactured for sale in Canada use a solid state
Daytime Running Lamps (DRL) relay installed in the
Junction Block (JB) instead of the conventional high
beam relay.
²Front Fog Lamp Relay- Vehicles equipped
with the optional front fog lamps have a front fog
lamp relay located in the Junction Block (JB).
²Hazard Switch- The hazard switch is located
near the center of the instrument panel and includes
the integral electronic combination flasher circuitry
for the hazard warning system and the turn signal
system.
²Headlamp Leveling Motor- A headlamp lev-
eling actuator motor is located on the back of each
headlamp housing of vehicles manufactured for cer-
tain markets where this equipment is required.
²Headlamp Leveling Switch- A thumbwheel
actuated headlamp leveling switch is mounted in the
driver side inboard instrument panel trim bezel of
vehicles manufactured for certain markets where this
equipment is required.
²High Beam Relay- A high beam relay is
located in the Junction Block (JB) of all vehicles
except those that are manufactured for sale in Can-
ada. Canadian vehicles have a solid state Daytime
Running Lamps (DRL) relay in the JB instead of the
high beam relay.
²Low Beam Relay- A low beam relay is located
in the Junction Block (JB) of all vehicles.
²Multi-Function Switch- The multi-function
switch is located on the top of the steering column,
just below the steering wheel. The multi-function
switch includes a left (lighting) control stalk and a
right (wiper) control stalk. The left control stalk is
dedicated to providing almost all of the driver con-
trols for both the exterior and interior lighting sys-
tems.
²Park Lamp Relay- A park lamp relay is
located in the Junction Block (JB) of all vehicles.
²Rear Fog Lamp Relay- Vehicles manufac-
tured for certain markets where rear fog lamps are
required equipment have a rear fog lamp relay
located in the Junction Block (JB).
1 - HEADLAMP UNIT (2)
2 - REPEATER LAMP UNIT (2)
3 - FRONT POSITION LAMP (2)
4 - FRONT LAMP UNIT (2)5 - FRONT FOG LAMP (2)
6 - CENTER HIGH MOUNTED STOP LAMP UNIT
7 - REAR LAMP UNIT
8 - LICENSE PLATE LAMP UNIT
8Ls - 4 LAMPSKJ
LAMPS/LIGHTING - EXTERIOR (Continued)

REMOVAL
OVERHEAD CONSOLE - REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the overhead console retaining screw,
located in the front of console near the windshield.
(3) Using your fingertips, grasp the sides of the
overhead console and pull straight down evenly to
disengage the two snap clips at the rear of the unit.
(4) Lower the overhead console far enough to
access the wire harness connectors.
(5) Disconnect the control module, courtesy lamps
and power sunroof switch electrical connectors, if
equipped.
(6) Remove the overhead console assembly from
the vehicle.
INSTALLATION
(1) Position the overhead console in the vehicle
and connect the wire harness connectors.
(2) Connect the control module, courtesy lamps
and power sunroof switch electrical connectors, if
equipped.
(3) Grasp the sides of the overhead console and
push straight up evenly to engage the two snap clips
at the rear of the unit.
(4) Install the overhead console retaining screw,
located in the front of console near the windshield.
Torque the screw to 1.2 N´m (10 in. lbs.).
(5) Connect the negative battery cable.
COMPASS/MINI-TRIP
COMPUTER
DESCRIPTION
The Compass Mini-Trip Computer (CMTC) is
located in the overhead console on models equipped
with this option. The Compass Mini-Trip Computer
module features a large Vacuum Fluorescent Display
(VFD) screen for displaying information, and four
back-lit push button function switches labeled C/T
(compass/thermometer), RESET, STEP, and US/M
(United States/Metric Scale).
The Compass Mini-Trip Computer module contains
a central processing unit and interfaces with other
electronic modules in the vehicle over the Program-
mable Communications Interface (PCI) data bus net-
work. The PCI data bus network allows the sharing
of sensor information. This helps to reduce wire har-
ness complexity, reduce internal controller hardware,
and reduce component sensor current loads. At the
same time, this system provides increased reliability,
enhanced diagnostics, and allows the addition of
many new feature capabilities.
The Compass Mini-Trip Computer module contains
six informational displays which can be displayed
using the four outer buttons on the overhead console.
When the vehicle is first turned ON:
²CMTC blanks the display for a half second
²Displays whatever was being viewed when the
ignition was last turned OFF
Fig. 5 Variance Settings
8M - 4 MESSAGE SYSTEMSKJ
OVERHEAD CONSOLE (Continued)

NOTE: Individual channels cannot be erased. Eras-
ing the transmitter codes will erase ALL pro-
grammed codes.
STANDARD PROCEDURE - SETTING
TRANSMITTER CODES
(1) Turn off the engine.
(2) Erase the factory test codes by pressing but-
tons 1 and 3. Release the buttons when the two
green lights begin to flash (about 20 seconds).
(3) Choose one of the three buttons to train. Place
the hand-held transmitter within one inch of the uni-
versal transmitter and push the buttons on both
transmitters. The green dot below the house symbol
will begin to flash slowly.
(4) When the red light on the universal transmit-
ter begins to flash rapidly (this may take as long as
60 seconds), release both buttons. Your universal
transmitter is now ªtrainedº. To train the other but-
tons, repeat Step 3 and Step 4. Be sure to keep your
hand-held transmitter in case you need to retrain the
universal transmitter.
AMBIENT TEMP SENSOR
DESCRIPTION
Ambient air temperature is monitored by the Com-
pass Mini-Trip Computer (CMTC) through ambient
temperature sensor messages received from the Body
Control Module (BCM) over the Programmable Com-
munications Interface (PCI) data bus network. The
BCM receives a hard wired input from the ambient
temperature sensor. The ambient temperature sensor
(Fig. 8) is a variable resistor mounted in front the
radiator, behind the grille, near the center of the
vehicle.
Refer toBody Control Modulein Electronic Con-
trol Modules. For complete circuit diagrams, refer to
the appropriate wiring information. The ambient
temperature sensor cannot be adjusted or repaired
and, if faulty or damaged, it must be replaced.
OPERATION
The ambient temperature sensor is a variable
resistor that operates on a five-volt reference signal
sent to it by the BCM. The resistance in the sensor
changes as temperature changes, changing the tem-
perature sensor signal circuit voltage to the BCM.
Based upon the resistance in the sensor, the BCM
senses a specific voltage on the temperature sensor
signal circuit, which it is programmed to correspond
to a specific temperature. The BCM then sends the
proper ambient temperature messages to the CMTC
over the PCI data bus.
The thermometer function is supported by the
ambient temperature sensor, a wiring circuit, the
Body Control Module (BCM), the Programmable
Communications Interface (PCI) data bus, and a por-
tion of the Compass Mini-Trip Computer module.
The ambient temperature sensor circuit can also be
diagnosed by referring toDiagnosis and Testing -
Ambient Temperature Sensor, and Diagnosis
and Testing - Ambient Temperature Sensor Cir-
cuit. If the temperature sensor and circuit are con-
firmed to be OK, but the temperature display is
inoperative or incorrect, refer toDiagnosis and
Testing - Compass Mini-Trip Computerin this
section. For complete circuit diagrams, refer to the
appropriate wiring information.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR
(1) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the ambient temperature sensor wire har-
ness connector.
(2) Measure the resistance of the ambient temper-
ature sensor. At ±40É C (±40É F), the sensor resis-
tance is 336 kilohms. At 55É C (140É F), the sensor
resistance is 2.488 kilohms. The sensor resistance
should read between these two values. If OK, refer to
Diagnosis and Testing - Ambient Temperature
Sensor Circuitin this group. If not OK, replace the
faulty ambient temperature sensor.
DIAGNOSIS AND TESTING - AMBIENT
TEMPERATURE SENSOR CIRCUIT
(1) Turn the ignition switch to the Off position.
Disconnect and isolate the battery negative cable.
Disconnect the ambient temperature sensor wire har-
ness connector and the Body Control Module wire
harness connector.
(2) Connect a jumper wire between the two termi-
nals in the body half of the ambient temperature sen-
sor wire harness connector.
Fig. 8 Ambient Temperature Sensor
KJMESSAGE SYSTEMS 8M - 9
UNIVERSAL TRANSMITTER (Continued)

are closed and the accelerator pedal is depressed.
The rolling door lock feature can be disabled if
desired.
This vehicle also offers several customer program-
mable features, which allows the selection of several
optional electronic features to suit individual prefer-
ences.
The power lock system for this vehicle can also be
operated remotely using the available Remote Key-
less Entry (RKE) system radio frequency transmit-
ters, if equipped.
Certain functions and features of the power lock
system rely upon resources shared with other elec-
tronic modules in the vehicle over the Programmable
Communications Interface (PCI) data bus network.
For proper diagnosis of these electronic modules or of
the PCI data bus network, the use of a DRBIIItscan
tool and the appropriate diagnostic information are
required.
REMOTE KEYLESS ENTRY
A Radio Frequency (RF) type Remote Keyless
Entry (RKE) system is an available factory-installed
option on this model. The RKE system allows the use
of a remote battery-powered radio transmitter to sig-
nal the Body Control Module (BCM) to actuate the
power lock system. The RKE receiver operates on
non-switched battery current through a fuse in the
Junction Block (JB), so that the system remains
operational, regardless of the ignition switch position.
The RKE transmitters are also equipped with a
Panic button. If the Panic button on the RKE trans-
mitter is depressed, the horn will sound and the
exterior lights will flash on the vehicle for about
three minutes, or until the Panic button is depressed
a second time. A vehicle speed of about 25.7 kilome-
ters-per-hour (15 miles-per-hour) will also cancel the
panic event.
The RKE system can also perform other functions
on this vehicle. If the vehicle is equipped with the
optional Vehicle Theft Security System (VTSS), the
RKE transmitter will arm the VTSS when the Lock
button is depressed, and disarm the VTSS when the
Unlock button is depressed.
The RKE system includes two transmitters when
the vehicle is shipped from the factory, but the sys-
tem can retain the vehicle access codes of up to four
transmitters. The transmitter codes are retained in
the RKE receiver memory, even if the battery is dis-
connected. If an RKE transmitter is faulty or lost,
new transmitter vehicle access codes can be pro-
grammed into the system using a DRBIIItscan tool.
This vehicle also offers several customer program-
mable features, which allows the selection of several
optional electronic features to suit individual prefer-ences. Customer programmable feature options
affecting the RKE system include:
²Remote Unlock Sequence- Allows the option
of having only the driver side front door unlock when
the RKE transmitter Unlock button is depressed the
first time. The remaining doors and the tailgate
unlock when the button is depressed a second time
within 5 seconds of the first unlock press. Another
option is having all doors and the tailgate unlock
upon the first depression of the RKE transmitter
Unlock button.
²Sound Horn on Lock- Allows the option of
having the horn sound a short chirp as an audible
verification that the RKE system received a valid
Lock request from the RKE transmitter, or having no
audible verification.
²Flash Lights with Lock and Unlock- Allows
the option of having the lights flash as an optical ver-
ification that the RKE system received a valid Lock
request or Unlock request from the RKE transmitter,
or having no optical verification.
²Programming Additional Transmitters-
Allows up to four transmitter vehicle access codes to
be stored in the receiver memory.
Certain functions and features of the RKE system
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. For diagnosis of these electronic
modules or of the PCI data bus network, the use of a
DRBIIItscan tool and the appropriate diagnostic
information are required.
TAILGATE / FLIP-UP GLASS POWER RELEASE
SYSTEM
A power operated tailgate / flip-up glass release
system is standard factory installed equipment on
this model. The entire system is controlled by the
Body Control Module (BCM). The tailgate / flip-up
glass power release system allows the flip-up glass
latch to be released electrically by actuating a switch
located integral to the outside tailgate handle. By
pulling the handle to the first detent or turning the
key cylinder to unlock, the flip-up glass will open.
Pulling the handle to the second detent will allow the
tailgate to open.
The tailgate / flip-up glass release system operates
on non-switched battery current supplied through a
fuse in the junction block so that the system remains
functional, regardless of the ignition switch position.
However, the BCM prevents the flip-up glass latch
from being actuated when the tailgate latch is
locked.
8N - 2 POWER LOCKSKJ
POWER LOCKS (Continued)

proper Diagnostic Procedures 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 relays for
them to perform their power lock system func-
tions.
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 Body Control Module (BCM) will set Diagnos-
tic Trouble Codes (DTC) for the power lock 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.
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 junction
Block (JB).
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/KEYLESS ENTRY TRANSMITTER - DIAG-
NOSIS AND TESTING) or (Refer to 8 - ELECTRI-
CAL/POWER LOCKS/REMOTE KEYLESS ENTRY
MODULE - DIAGNOSIS AND TESTING).
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 lock
switches. (Refer to 8 - ELECTRICAL/POWER
LOCKS/POWER LOCK SWITCH - 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).
DOOR LOCK / UNLOCK
SWITCH
DIAGNOSIS AND TESTING - DOOR LOCK/
UNLOCK SWITCH
(1) Remove the switch to be tested (Refer to 8 -
ELECTRICAL/POWER LOCKS/POWER LOCK
SWITCH - REMOVAL).
(2) Using an ohmmeter, Test switch for resistance
values (Fig. 1).
DOOR LOCK SWITCH TEST
SWITCH
POSITIONPINS RESISTANCE
VALUE
UNACTUATED 1 AND 4 5.0K OHM   10
%
LOCK 1 AND 4 1.4K OHM  10
%
UNLOCK 1 AND 4 426 OHM   10
%
(3) If test results are not obtained as shown in the
test table, replace the switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
Fig. 1 DOOR LOCK/UNLOCK SWITCH
8N - 4 POWER LOCKSKJ
POWER LOCKS (Continued)

(2) Remove the door trim panel (Fig. 2) (Refer to
23 - BODY/DOOR - FRONT/TRIM PANEL - REMOV-
AL).
(3) Disconnect electrical harness connector from
switch.
(4) From behind the door trim panel, gently pry
the switch from the door trim panel (Fig. 3).
INSTALLATION
(1) Press the switch into place.
(2) Connect the electrical harness connector to the
switch.(3) Install the door trim panel (Refer to 23 -
BODY/DOOR - FRONT/TRIM PANEL - INSTALLA-
TION).
(4) Connect the battery negative cable.
DOOR LOCK MOTOR
DESCRIPTION
The lock mechanisms are actuated by a reversible
electric motor mounted within each door and tailgate.
The power lock motors are integral to the door latch
units.
The power lock motors cannot be adjusted or
repaired and, if faulty or damaged, the door latch
unit must be replaced.
OPERATION
The door lock motors are controlled by relays. A
positive and negative battery connection to the two
motor terminals will cause the motor to move in one
direction. Reversing the current will cause the motor
to move in the opposite direction.
DIAGNOSIS AND TESTING - DOOR LOCK
MOTOR
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.
FLIP-UP GLASS RELEASE
SWITCH
DIAGNOSIS AND TESTING - FLIP-UP GLASS
RELEASE SWITCH
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the tailgate trim panel (Refer to 23 -
BODY/DECKLID/HATCH/LIFTGATE/TAILGATE/
TRIM PANEL - REMOVAL).
(3) Disconnect the wire harness connector.
Fig. 2 DOOR LOCK SWITCH
1 - DOOR TRIM PANEL
2 - DOOR LOCK SWITCH
3 - POWER MIRROR SWITCH
Fig. 3 DOOR LOCK/MIRROR SWITCH
1 - DOOR TRIM PANEL
2 - DOOR LOCK SWITCH
3 - POWER MIRROR SWITCH
KJPOWER LOCKS 8N - 5
DOOR LOCK / UNLOCK SWITCH (Continued)

Press and hold the transmitter UNLOCK button
for four to ten seconds. While pressing the UNLOCK
button in, press the LOCK button. Release both but-
tons.
This will toggle between Driver door first and
Unlock all doors function.
STANDARD PROCEDURE - RKE TRANSMITTER
PROGRAMING
New Remote Keyless Entry (RKE) transmitters can
be programed using the DRBIIItscan tool and the
proper Diagnostic Procedures manual. The DRBIIIt
scan tool can provide confirmation that the PCI data
bus is functional, and that all of the electronic mod-
ules are sending and receiving the proper messages
on the PCI data bus.
The following procedure can be used as long as one
functioning transmitter is available:
(1) Using the original transmitter, press the
UNLOCK button for 4 to 10 seconds.
(2) Without releasing the UNLOCK button, press
the PANIC button (within the 4 to 10 second inter-
val).
(3) Release both buttons.
(4) Press LOCK and UNLOCK simultaneously on
the original transmitter.
(5) Release both buttons.
(6) Press any button on the ORIGINAL transmit-
ter. A chime tone from the instrument cluster will
confirm the programming of the ORIGINAL trans-
mitter.
(7) On NEW transmitter, press LOCK and
UNLOCK simultaneously.
(8) Release both buttons.
(9) Press any button on the NEW transmitter. A
chime tone from the instrument cluster will confirm
the programming of the NEW transmitter.
(10) Up to four transmitters can be programed for
one vehicle.
SPECIFICATIONS - REMOTE KEYLESS ENTRY
TRANSMITTER
RANGE
Normal operation range is up to a distance of 3 to
7 meters (10 to 23 ft.) of the vehicle. Range may be
better or worse depending on the environment
around the vehicle.
TAILGATE CYLINDER LOCK
SWITCH
DESCRIPTION
The tailgate cylinder lock switch is integral to the
key lock cylinder inside the tailgate. The tailgate cyl-
inder lock switch is a normally-open momentary
switch that is hard wired directly to the Body Con-
trol Module (BCM), and closes a path to ground
through an internal resistor when the lock cylinder is
rotated to the unlock or lock position.
The tailgate cylinder lock switch cannot be
adjusted or repaired.
OPERATION
The tailgate cylinder lock switch is actuated when
the key is inserted in the lock cylinder and turned to
the unlock or lock position. The tailgate cylinder lock
switch closes a path to ground through an internal
resistor for the Body Control Module (BCM) when
the tailgate key lock cylinder is in the lock or unlock
position, and opens the ground path when the lock
cylinder is in the neutral position. The BCM reads
the switch status, then sends the proper switch sta-
tus messages to other electronic modules over the
Programmable Communications Interface (PCI) data
bus network. The tailgate cylinder lock switch unlock
status message is used by the BCM as an input for
Vehicle Theft Security System (VTSS) operation and
to tell the BCM to lock or unlock the tailgate. There
is no mechanical linkage between the tailgate key
cylinder and the latches.
DIAGNOSIS AND TESTING - TAILGATE
CYLINDER LOCK SWITCH
(1) Disconnect and isolate the battery negative
cable.
(2) Remove tailgate trim panel (Refer to 23 -
BODY/DECKLID/HATCH/LIFTGATE/TAILGATE/
TRIM PANEL - REMOVAL).
(3) Disconnect tailgate cylinder lock switch har-
ness connector.
(4) Using a ohmmeter, test for resistances as
shown in the Tailgate Cylinder Lock Switch Table.
KJPOWER LOCKS 8N - 9
REMOTE KEYLESS ENTRY TRANSMITTER (Continued)

is located on the back side of each vertical member of
the radiator support.
²Passenger Airbag- The passenger airbag is
located on the instrument panel, beneath the passen-
ger airbag door on the instrument panel above the
glove box on the passenger side of the vehicle.
²Passenger Knee Blocker- The passenger knee
blocker is a structural reinforcement that is integral
to and concealed within the glove box door.
²Seat Belt Tensioner- The seat belt tensioner
is integral to the driver side front seat belt retractor
unit on vehicles equipped with dual front airbags.
²Side Impact Airbag Control Module-Two
Side Impact Airbag Control Modules (SIACM) are
used on vehicles with the optional side curtain air-
bags, one left side and one right side. One SIACM is
located behind the B-pillar trim near the base of each
B-pillar.
²Side Curtain Airbag- In vehicles equipped
with this option, a side curtain airbag is located on
each inside roof side rail above the headliner, and
extends from the A-pillar to just beyond the C-pillar.
The ACM, both SIACMs, and the EMIC each con-
tain a central processing unit and programming that
allow them to communicate with each other using
the Programmable Communication Interface (PCI)
data bus network. This method of communication is
used by the ACM for control of the airbag indicator
on all models equipped with dual front airbags.
(Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/COMMUNICATION - DESCRIP-
TION).
Hard wired circuitry connects the supplemental
restraint system components to each other through
the electrical system of the vehicle. These hard wired
circuits are integral to several wire harnesses, which
are routed throughout the vehicle and retained by
many different methods. These circuits may be con-
nected to each other, to the vehicle electrical system,
and to the supplemental restraint system compo-
nents through the use of a combination of soldered
splices, splice block connectors, and many different
types of wire harness terminal connectors and insu-
lators. 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
harness connectors, splices and grounds.
OPERATION
ACTIVE RESTRAINTS The primary passenger
restraints in this or any other vehicle are the stan-
dard equipment factory-installed seat belts. Seat
belts are referred to as an active restraint because
the vehicle occupants are required to physically fas-ten and properly adjust these restraints in order to
benefit from them. See the owner's manual in the
vehicle glove box for more information on the fea-
tures, use and operation of all of the factory-installed
active restraints.
PASSIVE RESTRAINTS The passive restraints
system is referred to as a supplemental restraint sys-
tem because they were designed and are intended to
enhance the protection for the vehicle occupants of
the vehicleonlywhen used in conjunction with the
seat belts. They are referred to as passive systems
because the vehicle occupants are not required to do
anything to make them operate; however, the vehicle
occupants must be wearing their seat belts in order
to obtain the maximum safety benefit from the facto-
ry-installed supplemental restraint systems.
The supplemental restraint system electrical cir-
cuits are continuously monitored and controlled by a
microprocessor and software contained within the
Airbag Control Module (ACM) and, on vehicles
equipped with the side curtain airbags, both Side
Impact Airbag Control Modules (SIACM). An airbag
indicator in the ElectroMechanical Instrument Clus-
ter (EMIC) illuminates for about seven seconds as a
bulb test each time the ignition switch is turned to
the On or Start positions. Following the bulb test,
the airbag indicator is turned on or off by the ACM
to indicate the status of the supplemental restraint
system. If the airbag indicator comes on at any time
other than during the bulb test, it indicates that
there is a problem in the supplemental restraint sys-
tem electrical circuits. Such a problem may cause air-
bags not to deploy when required, or to deploy when
not required.
Deployment of the supplemental restraints
depends upon the angle and severity of an impact.
Deployment is not based upon vehicle speed; rather,
deployment is based upon the rate of deceleration as
measured by the forces of gravity (G force) upon the
impact sensors. When an impact is severe enough,
the microprocessor in the ACM or the SIACM signals
the inflator unit of the airbag module to deploy the
airbag. The seat belt tensioner is provided with a
deployment signal by the ACM in conjunction with
the driver airbag. During a frontal vehicle impact,
the knee blockers work in concert with properly fas-
tened and adjusted seat belts to restrain both the
driver and the front seat passenger in the proper
position for an airbag deployment. The knee blockers
also absorb and distribute the crash energy from the
driver and the front seat passenger to the structure
of the instrument panel. The seat belt tensioner
removes the slack from the driver side front seat belt
to provide further assurance that the driver is prop-
erly positioned and restrained for an airbag deploy-
ment.
8O - 4 RESTRAINTSKJ
RESTRAINTS (Continued)