2002 JEEP LIBERTY service indicator

(3) Remove the compass mini-trip computer from
the overhead console.
INSTALLATION
(1) Install the compass mini-trip computer in the
overhead console. Align the compass mini-trip com-
puter guides on the housing with the grooves of the
console.
(2) Install the mounting screws and install the
map lamp wire connector on the compass mini-trip
computer. Make sure the LOOP of wire that was
clipped into the compass mini-trip computer module
housing is properly clipped into the new module
before the console is placed back into the headliner.
(3) Install the overhead console, refer to Console
Installation in this section.
UNIVERSAL TRANSMITTER
DESCRIPTION
On some KJ models a Universal Transmitter trans-
ceiver is standard factory-installed equipment. The
universal transmitter transceiver is integral to the
Compass Mini-Trip Computer (CMTC), which is
located in the overhead console. The only visible com-
ponent of the universal transmitter are the three
transmitter push buttons (Fig. 7) centered between
the four CMTC push buttons located just rearward of
the CMTC display screen in the overhead console.
The three universal transmitter push buttons are
identified with one, two or three light indicators so
that they be easily identified by sight or by feel.
Each of the three universal transmitter push but-
tons controls an independent radio transmitter chan-
nel. Each of these three channels can be trained totransmit a different radio frequency signal for the
remote operation of garage door openers, motorized
gate openers, home or office lighting, security sys-
tems or just about any other device that can be
equipped with a radio receiver in the 286 to 399
MegaHertz (MHz) frequency range for remote opera-
tion. The universal transmitter is capable of operat-
ing systems using either rolling code or non-rolling
code technology.
The CMTC module displays messages and a small
house-shaped icon with one, two or three dots corre-
sponding to the three transmitter buttons to indicate
the status of the Universal Transmitter.
The Universal Transmitter cannot be repaired, and
is available for service only as a unit with the CMTC
module. This unit includes the push button switches
and the plastic module and display lens. If any of
these components is faulty or damaged, the complete
CMTC module must be replaced.
OPERATION
The universal transmitter operates on a non-
switched source of battery current so the unit will
remain functional, regardless of the ignition switch
position. For more information on the features, pro-
gramming procedures and operation of the universal
transmitter, see the owner's manual in the vehicle
glove box.
DIAGNOSIS AND TESTING - UNIVERSAL
TRANSMITTER
If the Universal Transmitter is inoperative, but the
Compass Mini-Trip Computer (CMTC) is operating
normally, see the owner's manual in the vehicle glove
box for instructions on training the universal trans-
mitter. Retrain the universal transmitter with a
known good transmitter as instructed in the owner's
manual and test the universal transmitter operation
again. If the unit is still inoperative, replace the
faulty universal transmitter and CMTC module as a
unit. If both the universal transmitter and the CMTC
module are inoperative, refer toDiagnosis and
Testing the Compass Mini-Trip Computerin this
section for further diagnosis. For complete circuit
diagrams, refer toOverhead Consolein Wiring
Diagrams.
STANDARD PROCEDURE
STANDARD PROCEDURE - ERASING
TRANSMITTER CODES
To erase the universal transmitter codes, simply
hold down buttons 1 and 3 until the two green dots
below the house symbol begin to flash.
Fig. 7 Overhead Console With Universal Transmitter
8M - 8 MESSAGE SYSTEMSKJ
COMPASS/MINI-TRIP COMPUTER (Continued)

An occupant restraint system is standard factory-
installed safety equipment on this model. Available
occupant restraints for this model include both active
and passive types. Active restraints are those which
require the vehicle occupants to take some action to
employ, such as fastening a seat belt; while passive
restraints require no action by the vehicle occupants
to be employed (Fig. 1).
ACTIVE RESTRAINTS The active restraints for
this model include:
²Front Seat Belts- Both front seating positions
are equipped with three-point seat belt systems
employing a lower B-pillar mounted inertia latch-
type retractor, height-adjustable upper B-pillar
mounted turning loops, a traveling lower seat belt
anchor secured to the outboard side of the seat
frame, and a traveling end-release seat belt buckle
secured to the inboard side of the seat frame. Both
front seat belt buckles include an integral Hall-effect
seat belt switch that detects whether its respective
seat belt has been fastened.
²Rear Seat Belts- All three rear seating posi-
tions are equipped with three-point seat belt sys-
tems. The outboard seating position belts employ a
lower C-pillar mounted inertia latch-type retractor, a
fixed position upper C-pillar mounted turning loop,
and a fixed lower seat belt anchor secured to the
floor panel. The rear seat center seating position belt
has an inertia latch-type retractor that is integral to
the rear seat back panel, and a cable from the seat
back latch locks the center belt retractor spool unless
the seat back is fully latched. The rear seat center
seating position belt lower anchor is secured to the
floor panel. All three rear seat belts have fixed end-
release seat belt buckles secured to the floor panel, a
single buckle unit on the right side and a double
buckle unit on the left side.
²Child Seat Tether Anchors- All vehicles are
equipped with three, fixed-position, child seat tether
anchors. Two anchors are integral to the back of the
right rear seat back panel, and one is integral to the
left rear seat back panel.
PASSIVE RESTRAINTS The passive restraints
available for this model include the following:
²Dual Front Airbags- Multistage driver and
front passenger airbags are available for this model.
This airbag system is a passive, inflatable, Supple-
mental Restraint System (SRS) and vehicles with
this equipment can be readily identified by the ªSRS
- AIRBAGº logo molded into the driver airbag trim
cover in the center of the steering wheel and also
into the passenger airbag door on the instrument
panel above the glove box (Fig. 2). Vehicles with the
airbag system can also be identified by the airbag
indicator, which will illuminate in the instrument
cluster for about seven seconds as a bulb test eachtime the ignition switch is turned to the On position.
A pyrotechnic-type seat belt tensioner is integral to
the driver side front seat belt retractor mounted on
the lower B-pillar of all models equipped with dual
front airbags.
²Side Curtain Airbags- Optional side curtain
airbags are available for this model when it is also
equipped with dual front airbags. This airbag system
is a passive, inflatable, Supplemental Restraint Sys-
tem (SRS) and vehicles with this equipment can be
readily identified by a molded identification trim but-
ton with the ªSRS - AIRBAGº logo located on the
headliner above each B-pillar (Fig. 2).
The supplemental restraint system includes the
following major components, which are described in
further detail elsewhere in this service information:
²Airbag Control Module- The Airbag Control
Module (ACM) is also sometimes referred to as the
Occupant Restraint Controller (ORC). The ACM is
located on a mount on the floor panel transmission
tunnel, below the center of the instrument panel.
²Airbag Indicator- The airbag indicator is inte-
gral to the ElectroMechanical Instrument Cluster
(EMIC), which is located on the instrument panel in
front of the driver.
²Clockspring- The clockspring is located near
the top of the steering column, directly beneath the
steering wheel.
²Driver Airbag- The driver airbag is located in
the center of the steering wheel, beneath the driver
airbag trim cover.
²Driver Knee Blocker- The driver knee blocker
is a structural unit secured to the back side of and
integral to the instrument panel steering column
opening cover.
²Front Impact Sensor- Two front impact sen-
sors are used on vehicles equipped with dual front
airbags, one left side and one right side. One sensor
Fig. 2 SRS Logo
KJRESTRAINTS 8O - 3
RESTRAINTS (Continued)

Typically, the vehicle occupants recall more about
the events preceding and following a collision than
they have of an airbag deployment itself. This is
because the airbag deployment and deflation occur so
rapidly. In a typical 48 kilometer-per-hour (30 mile-
per-hour) barrier impact, from the moment of impact
until the airbags are fully inflated takes about 40
milliseconds. Within one to two seconds from the
moment of impact, the airbags are almost entirely
deflated. The times cited for these events are approx-
imations, which apply only to a barrier impact at the
given speed. Actual times will vary somewhat,
depending upon the vehicle speed, impact angle,
severity of the impact, and the type of collision.
When the ACM monitors a problem in any of the
dual front airbag system circuits or components,
including the seat belt tensioner, it stores a fault
code or Diagnostic Trouble Code (DTC) in its memory
circuit and sends an electronic message to the EMIC
to turn on the airbag indicator. When the SIACM
monitors a problem in any of the side curtain airbag
system circuits or component, it stores a fault code or
Diagnostic Trouble Code (DTC) in its memory circuit
and sends an electronic message to the ACM, and the
ACM sends an electronic message to the EMIC to
turn on the airbag indicator. Proper testing of the
airbag system components, the Programmable Com-
munication Interface (PCI) data bus, the data bus
message inputs to and outputs from the EMIC, the
SIACM, or the ACM, as well as the retrieval or era-
sure of a DTC from the ACM, SIACM, or EMIC
requires the use of a DRBIIItscan tool. Refer to the
appropriate diagnostic information.
See the owner's manual in the vehicle glove box for
more information on the features, use and operation
of all of the factory-installed passive restraints.
WARNING - RESTRAINT SYSTEM
WARNING: DURING AND FOLLOWING ANY SEAT
BELT SERVICE, CAREFULLY INSPECT ALL SEAT
BELTS, BUCKLES, MOUNTING HARDWARE, AND
RETRACTORS FOR PROPER INSTALLATION,
OPERATION, OR DAMAGE. REPLACE ANY BELT
THAT IS CUT, FRAYED, OR TORN. STRAIGHTEN
ANY BELT THAT IS TWISTED. TIGHTEN ANY
LOOSE FASTENERS. REPLACE ANY BELT THAT
HAS A DAMAGED OR INOPERATIVE BUCKLE OR
RETRACTOR. REPLACE ANY BELT THAT HAS A
BENT OR DAMAGED LATCH PLATE OR ANCHOR
PLATE. NEVER ATTEMPT TO REPAIR A SEAT BELT
COMPONENT. ALWAYS REPLACE DAMAGED OR
FAULTY SEAT BELT COMPONENTS WITH THE COR-
RECT, NEW AND UNUSED REPLACEMENT PARTS
LISTED IN THE DAIMLERCHRYSLER MOPAR PARTS
CATALOG.WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSOR, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
WARNING: AN AIRBAG INFLATOR UNIT MAY CON-
TAIN SODIUM AZIDE AND POTASSIUM NITRATE.
THESE MATERIALS ARE POISONOUS AND
EXTREMELY FLAMMABLE. CONTACT WITH ACID,
WATER, OR HEAVY METALS MAY PRODUCE HARM-
FUL AND IRRITATING GASES (SODIUM HYDROXIDE
IS FORMED IN THE PRESENCE OF MOISTURE) OR
COMBUSTIBLE COMPOUNDS. AN AIRBAG INFLA-
TOR UNIT MAY ALSO CONTAIN A GAS CANISTER
PRESSURIZED TO OVER 2500 PSI. DO NOT
ATTEMPT TO DISMANTLE AN AIRBAG UNIT OR
TAMPER WITH ITS INFLATOR. DO NOT PUNCTURE,
INCINERATE, OR BRING INTO CONTACT WITH
ELECTRICITY. DO NOT STORE AT TEMPERATURES
EXCEEDING 93É C (200É F).
WARNING: WHEN HANDLING A SEAT BELT TEN-
SIONER RETRACTOR, PROPER CARE SHOULD BE
EXERCISED TO KEEP FINGERS OUT FROM UNDER
THE RETRACTOR COVER AND AWAY FROM THE
SEAT BELT WEBBING WHERE IT EXITS FROM THE
RETRACTOR COVER.
WARNING: REPLACE ALL RESTRAINT SYSTEM
COMPONENTS ONLY WITH PARTS SPECIFIED IN
THE DAIMLERCHRYSLER MOPAR PARTS CATA-
LOG. SUBSTITUTE PARTS MAY APPEAR INTER-
CHANGEABLE, BUT INTERNAL DIFFERENCES MAY
RESULT IN INFERIOR OCCUPANT PROTECTION.
KJRESTRAINTS 8O - 5
RESTRAINTS (Continued)

The ACM housing also has an integral ground lug
with a tapped hole that protrudes from the lower left
rear corner of the unit. This lug provides a case
ground to the ACM when a ground screw is installed
through the left side of the mounting bracket. Two
molded plastic electrical connector receptacles exit
the right side of the ACM housing. The smaller of the
two receptacles contains twelve terminal pins, while
the larger one contains twenty-three. These terminal
pins connect the ACM to the vehicle electrical system
through two dedicated take outs and connectors of
the instrument panel wire harness.
A molded rubber protective cover is installed
loosely over the ACM to protect the unit from con-
densation or coolant leaking from a damaged or
faulty heater-air conditioner unit housing. An inte-
gral flange on the left side of the cover is secured to
the floor panel transmission tunnel with a short
piece of double-faced tape as an assembly aid during
the manufacturing process, but this tape does not
require replacement following service removal.
The impact sensor and safing sensor internal to
the ACM are calibrated for the specific vehicle, and
are only serviced as a unit with the ACM. The ACM
cannot be repaired or adjusted and, if damaged or
faulty, it must be replaced. The ACM cover is avail-
able for separate service replacement.
OPERATION
The microprocessor in the Airbag Control Module
(ACM) contains the front supplemental restraint sys-
tem logic circuits and controls all of the front supple-
mental restraint system components. The ACM uses
On-Board Diagnostics (OBD) and can communicate
with other electronic modules in the vehicle as well
as with the DRBIIItscan tool using the Programma-
ble Communications Interface (PCI) data bus net-
work. This method of communication is used for
control of the airbag indicator in the ElectroMechani-
cal Instrument Cluster (EMIC) and for supplemental
restraint system diagnosis and testing through the
16-way data link connector located on the driver side
lower edge of the instrument panel. (Refer to 8 -
ELECTRICAL/INSTRUMENT CLUSTER/AIRBAG
INDICATOR - OPERATION).
The ACM microprocessor continuously monitors all
of the front supplemental restraint system electrical
circuits to determine the system readiness. If the
ACM detects a monitored system fault, it sets an
active and stored Diagnostic Trouble Code (DTC) and
sends electronic messages to the EMIC over the PCI
data bus to turn on the airbag indicator. An active
fault only remains for the duration of the fault or in
some cases the duration of the current ignition
switch cycle, while a stored fault causes a DTC to be
stored in memory by the ACM. For some DTCs, if afault does not recur for a number of ignition cycles,
the ACM will automatically erase the stored DTC.
For other internal faults, the stored DTC is latched
forever.
On models equipped with optional side curtain air-
bags, the ACM communicates with both the left and
right Side Impact Airbag Control Modules (SIACM)
over the PCI data bus. The SIACM notifies the ACM
when it has detected a monitored system fault and
stored a DTC in memory for its respective side cur-
tain airbag system, and the ACM sets a DTC and
controls the airbag indicator operation accordingly.
The ACM also monitors a Hall effect-type seat belt
switch located in the buckle of each front seat belt to
determine whether the seatbelts are buckled, and
provides an input to the EMIC over the PCI data bus
to control the seatbelt indicator operation based upon
the status of the driver side front seat belt switch.
The ACM receives battery current through two cir-
cuits; a fused ignition switch output (run) circuit
through a fuse in the Junction Block (JB), and a
fused ignition switch output (run-start) circuit
through a second fuse in the JB. The ACM has a case
ground through a lug on the bottom of the ACM
housing that is secured with a ground screw to the
left side of the ACM mounting bracket. The ACM
also receives a power ground through a ground cir-
cuit and take out of the instrument panel wire har-
ness. This take out has a single eyelet terminal
connector that is secured by a second ground screw
to the left side of the ACM mounting bracket. These
connections allow the ACM to be operational when-
ever the ignition switch is in the Start or On posi-
tions. The ACM also contains an energy-storage
capacitor. When the ignition switch is in the Start or
On positions, this capacitor is continually being
charged with enough electrical energy to deploy the
airbags for up to one second following a battery dis-
connect or failure. The purpose of the capacitor is to
provide backup supplemental restraint system pro-
tection in case there is a loss of battery current sup-
ply to the ACM during an impact.
Two sensors are contained within the ACM, an
electronic impact sensor and a safing sensor. The
ACM also monitors inputs from two remote front
impact sensors located on the back of the right and
left vertical members of the radiator support near
the front of the vehicle. The electronic impact sensors
are accelerometers that sense the rate of vehicle
deceleration, which provides verification of the direc-
tion and severity of an impact. The safing sensor is
an electromechanical sensor within the ACM that
provides an additional logic input to the ACM micro-
processor. The safing sensor is a normally open
switch that is used to verify the need for an airbag
deployment by detecting impact energy of a lesser
8O - 10 RESTRAINTSKJ
AIRBAG CONTROL MODULE (Continued)

FRONT IMPACT SENSOR
DESCRIPTION
Two front impact sensors are used on this model,
one each for the left and right sides of the vehicle
(Fig. 17). These sensors are mounted remotely from
the impact sensor that is internal to the Airbag Con-
trol Module (ACM). Each front sensor is secured with
two screws to the backs of the right and left vertical
members of the radiator support within the engine
compartment. The sensor housing has an integral
connector receptacle and two integral mounting
points each with a metal sleeve to provide crush pro-
tection.
The right and left front impact sensors are identi-
cal in construction and calibration with two excep-
tions:
²On models equipped with an optional 2.4L gaso-
line engine, the left front impact sensor includes a
shim that moves the sensor three millimeters toward
the rear of the vehicle on the left vertical member of
the radiator support for additional clearance that is
required for that application.
²On models equipped with an optional diesel
engine, the left front impact sensor includes a
stamped metal mounting bracket that rotates theconnector receptacle end of the sensor toward the
outboard side of the vehicle for additional clearance
that is required for that application.
A cavity in the center of the molded black plastic
impact sensor housing contains the electronic cir-
cuitry of the sensor which includes an electronic com-
munication chip and an electronic impact sensor.
Potting material fills the cavity to seal and protect
the internal electronic circuitry and components. The
front impact sensors are each connected to the vehi-
cle electrical system through a dedicated take out
and connector of the headlamp and dash wire har-
ness.
The impact sensors cannot be repaired or adjusted
and, if damaged or faulty, they must be replaced. The
mounting bracket for the left front impact sensor on
models with a diesel engine is serviced as a unit with
that sensor.
OPERATION
The front impact sensors are electronic accelerom-
eters that sense the rate of vehicle deceleration,
which provides verification of the direction and sever-
ity of an impact. Each sensor also contains an elec-
tronic communication chip that allows the unit to
communicate the sensor status as well as sensor
fault information to the microprocessor in the Airbag
Control Module (ACM). The ACM microprocessor con-
tinuously monitors all of the front passive restraint
system electrical circuits to determine the system
readiness. If the ACM detects a monitored system
fault, it sets a Diagnostic Trouble Code (DTC) and
controls the airbag indicator operation accordingly.
The impact sensors each receive battery current and
ground through dedicated left and right sensor plus and
minus circuits from the ACM. The impact sensors and
the ACM communicate by modulating the voltage in the
sensor plus circuit. The hard wired circuits between the
front impact sensors and the ACM may be diagnosed
and tested using conventional diagnostic tools and pro-
cedures. However, conventional diagnostic methods will
not prove conclusive in the diagnosis of the ACM or the
impact sensors. The most reliable, efficient, and accu-
rate means to diagnose the impact sensors, the ACM,
and the electronic message communication between the
sensors and the ACM requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic informa-
tion.
Fig. 17 Front Impact Sensor
1 - SENSOR
2 - CONNECTOR RECEPTACLE
KJRESTRAINTS 8O - 21

through the tube. The rack gear engages a pinion
gear that drives a gear set in the tensioner housing,
which drives the seat belt retractor spool causing the
slack to be removed from the driver side front seat
belt. Removing excess slack from the driver side front
seat belt not only keeps the occupant properly posi-
tioned for an airbag deployment following a frontal
impact of the vehicle, but also helps to reduce inju-
ries that the occupant of the driver side front seat
might experience in these situations as a result of a
harmful contact with the steering wheel and/or steer-
ing column. Also, the seat belt tensioner has a tor-
sion bar mechanism that is designed to deform in
order to control the loading being applied to the occu-
pant of the driver side front seat by the seat belt dur-
ing a frontal impact, further reducing the potential
for occupant injuries.
The ACM monitors the condition of the seat belt
tensioner through circuit resistance, and will illumi-
nate the airbag indicator in the ElectroMechanical
Instrument Cluster (EMIC) and store a Diagnostic
Trouble Code (DTC) for any fault that is detected.
For proper diagnosis of the seat belt tensioner, a
DRBIIItscan tool is required. Refer to the appropri-
ate diagnostic information.
SEAT BELT TURNING LOOP
ADJUSTER
REMOVAL
WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS, DISABLE THE SUPPLEMENTAL RESTRAINT
SYSTEM BEFORE ATTEMPTING ANY STEERING
WHEEL, STEERING COLUMN, DRIVER AIRBAG,
PASSENGER AIRBAG, SEAT BELT TENSIONER,
FRONT IMPACT SENSORS, SIDE CURTAIN AIRBAG,
OR INSTRUMENT PANEL COMPONENT DIAGNOSIS
OR SERVICE. DISCONNECT AND ISOLATE THE
BATTERY NEGATIVE (GROUND) CABLE, THEN
WAIT TWO MINUTES FOR THE SYSTEM CAPACI-
TOR TO DISCHARGE BEFORE PERFORMING FUR-
THER DIAGNOSIS OR SERVICE. THIS IS THE ONLY
SURE WAY TO DISABLE THE SUPPLEMENTAL
RESTRAINT SYSTEM. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.
WARNING: DURING AND FOLLOWING ANY SEAT
BELT SERVICE, CAREFULLY INSPECT ALL SEAT
BELTS, BUCKLES, MOUNTING HARDWARE, AND
RETRACTORS FOR PROPER INSTALLATION,
OPERATION, OR DAMAGE. REPLACE ANY BELTTHAT IS CUT, FRAYED, OR TORN. STRAIGHTEN
ANY BELT THAT IS TWISTED. TIGHTEN ANY
LOOSE FASTENERS. REPLACE ANY BELT THAT
HAS A DAMAGED OR INOPERATIVE BUCKLE OR
RETRACTOR. REPLACE ANY BELT THAT HAS A
BENT OR DAMAGED LATCH PLATE OR ANCHOR
PLATE. NEVER ATTEMPT TO REPAIR A SEAT BELT
COMPONENT. ALWAYS REPLACE DAMAGED OR
FAULTY SEAT BELT COMPONENTS WITH THE COR-
RECT, NEW AND UNUSED REPLACEMENT PARTS
LISTED IN THE MOPAR PARTS CATALOG.
(1) Disconnect and isolate the battery negative
cable. Wait two minutes for the system capacitor to
discharge before further service.
(2) Unsnap and lift the trim cover to access the
nut that secures the front seat belt turning loop to
the height adjuster on the upper B-pillar.
(3) Remove the nut that secures the seat belt turn-
ing loop to the height adjuster stud on the upper
B-pillar.
(4) Remove the seat belt turning loop from the
height adjuster stud.
(5) Remove the upper trim from the inside of the
B-pillar. (Refer to 23 - BODY/INTERIOR/B-PILLAR
UPPER TRIM - REMOVAL).
(6) Remove the screw that secures the seat belt
turning loop adjuster to the upper B-pillar (Fig. 35).
(7) Pull the upper end of the turning loop adjuster
away from the B-pillar far enough to disengage the
hooks on the lower end of the adjuster from the slots
in the B-pillar.
(8) Remove the seat belt turning loop adjuster
from the B-pillar.
Fig. 35 Seat Belt Turning Loop Adjuster Remove/
Install
1 - SCREW
2 - B-PILLAR
3 - ADJUSTER
KJRESTRAINTS 8O - 37
SEAT BELT TENSIONER (Continued)

(10) Reinstall the headliner into the vehicle. (Refer
to 23 - BODY/INTERIOR/HEADLINER - INSTALLA-
TION).
(11) Reinstall the lower trim onto the inside of the
B-pillar. (Refer to 23 - BODY/INTERIOR/B-PILLAR
LOWER TRIM - INSTALLATION).
(12) Do not reconnect the battery negative cable at
this time. The airbag system verification test proce-
dure should be performed following service of any
supplemental restraint system component. (Refer to
8 - ELECTRICAL/RESTRAINTS - STANDARD PRO-
CEDURE - VERIFICATION TEST).
SIDE IMPACT AIRBAG
CONTROL MODULE
DESCRIPTION
On vehicles equipped with the optional side curtain
airbags, a Side Impact Airbag Control Module
(SIACM) and its mounting bracket are secured with
four screws to the sill panel at the base of each B-pil-
lar behind the lower B-pillar trim (Fig. 43). Con-
cealed within a hollow in the center of the die cast
aluminum SIACM housing is the electronic circuitry
of the SIACM which includes a microprocessor and
an electronic impact sensor. The SIACM housing is
secured to a stamped steel mounting bracket, which
is unique for the right or left side application of this
component. The SIACM should never be removed
from its mounting bracket. The housing also receives
a case ground through this mounting bracket when it
is secured to the vehicle. A molded plastic electrical
connector receptacle that exits the top of the SIACMhousing connects the unit to the vehicle electrical
system through a dedicated take out and connector of
the body wire harness. Both the SIACM housing and
its electrical connection are sealed to protect the
internal electronic circuitry and components against
moisture intrusion.
The impact sensor internal to the SIACM is cali-
brated for the specific vehicle, and is only serviced as
a unit with the SIACM. The SIACM cannot be
repaired or adjusted and, if damaged or faulty, it
must be replaced.
OPERATION
The microprocessor in the Side Impact Airbag Con-
trol Module (SIACM) contains the side curtain airbag
system logic circuits and controls all of the features
of only the side curtain airbag mounted on the same
side of the vehicle as the SIACM. The SIACM uses
On-Board Diagnostics (OBD) and can communicate
with other electronic modules in the vehicle as well
as with the DRBIIItscan tool using the Programma-
ble Communications Interface (PCI) data bus net-
work. This method of communication is used by the
SIACM to communicate with the Airbag Control
Module (ACM) and for supplemental restraints sys-
tem diagnosis and testing through the 16-way data
link connector located on the driver side lower edge
of the instrument panel. The ACM communicates
with both the left and right SIACM over the PCI
data bus.
The SIACM microprocessor continuously monitors
all of the side curtain airbag electrical circuits to
determine the system readiness. If the SIACM
detects a monitored system fault, it sets an active
and stored Diagnostic Trouble Code (DTC) and sends
electronic messages to the ACM over the PCI data
bus. The ACM will respond by sending an electronic
message to the EMIC to turn on the airbag indicator,
and by storing a DTC that will indicate whether the
left or the right SIACM has stored the DTC that ini-
tiated the airbag indicator illumination. An active
fault only remains for the current ignition switch
cycle, while a stored fault causes a DTC to be stored
in memory by the SIACM. For some DTCs, if a fault
does not recur for a number of ignition cycles, the
SIACM will automatically erase the stored DTC. For
other internal faults, the stored DTC is latched for-
ever.
The SIACM receives battery current on a fused
ignition switch output (run-start) circuit through a
fuse in the Junction Block (JB). The SIACM has a
case ground through its mounting bracket and also
receives a power ground through a ground circuit
and take out of the body wire harness. This take out
has a single eyelet terminal connector that is secured
by a ground screw to the front seat front crossmem-
Fig. 43 Side Impact Airbag Control Module
1 - BRACKET (RIGHT SHOWN)
2 - CONNECTOR RECEPTACLE
3 - SIACM
KJRESTRAINTS 8O - 43
SIDE CURTAIN AIRBAG (Continued)

²Combination Flasher- An electronic combina-
tion flasher is integral to the hazard switch located
in the center of the instrument panel above the
radio. (Refer to 8 - ELECTRICAL/LAMPS/LIGHT-
ING - EXTERIOR/COMBINATION FLASHER -
DESCRIPTION).
²Door Ajar Switch- A door ajar switch is inte-
gral to the latch of each door in the vehicle. (Refer to
8 - ELECTRICAL/LAMPS/LIGHTING - INTERIOR/
DOOR AJAR SWITCH - DESCRIPTION).
²Door Cylinder Lock Switch- For North
American vehicles only, a door cylinder lock switch is
located on the back of the lock cylinder of each front
door. (Refer to 8 - ELECTRICAL/VEHICLE THEFT
SECURITY/DOOR CYLINDER LOCK SWITCH -
DESCRIPTION).
²Flip-Up Glass Ajar Switch- A flip-up glass
ajar switch is integral to the rear flip-up glass latch,
located on the top of the tailgate near the center.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/FLIP-UP GLASS AJAR SWITCH -
DESCRIPTION).
²Hood Ajar Switch- A hood ajar switch is
located beneath the hood panel on the right inner
fender side shield of vehicles built for sale in certain
markets where it is required equipment. (Refer to 8 -
ELECTRICAL/VEHICLE THEFT SECURITY/HOOD
AJAR SWITCH - DESCRIPTION).
²Horn Relay- A horn relay is located on the
Junction Block (JB) under the driver side outboard
end of the instrument panel. (Refer to 8 - ELECTRI-
CAL/HORN/HORN RELAY - DESCRIPTION).
²Intrusion Transceiver Module- An Intrusion
Transceiver Module (ITM) is located near the center
of the headliner in the passenger compartment of
vehicles built for sale in certain markets where it is
required equipment. (Refer to 8 - ELECTRICAL/VE-
HICLE THEFT SECURITY/UK SECURITY SYSTEM
MODULE - DESCRIPTION).
²Security Indicator- A security indicator is
located in the ElectroMechanical Instrument Cluster
(EMIC) on the instrument panel in front of the driver
side front seat. (Refer to 8 - ELECTRICAL/INSTRU-
MENT CLUSTER/SECURITY INDICATOR -
DESCRIPTION).
²Siren- An alarm siren is located on the front
extension of the right front wheel house panel in the
engine compartment of vehicles built for sale in cer-
tain markets where it is required equipment. (Refer
to 8 - ELECTRICAL/VEHICLE THEFT SECURITY/
SIREN - DESCRIPTION).
²Tailgate Ajar Switch- A tailgate ajar switch is
integral to the latch for the tailgate in the vehicle.
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
INTERIOR/TAILGATE AJAR SWITCH - DESCRIP-
TION).SENTRY KEY IMMOBILIZER SYSTEM The Sen-
try Key Immobilizer System (SKIS) is available as a
factory-installed option on this model. Vehicles
equipped with the Vehicle Theft Alarm (VTA) are also
equipped with SKIS. The SKIS provides passive vehi-
cle protection by preventing the engine from operat-
ing unless a valid electronically encoded key is
detected in the ignition lock cylinder. The SKIS
includes the following major components, which are
described in further detail elsewhere in this service
information:
²Powertrain Control Module- The Powertrain
Control Module (PCM) is located on the left inner
fender shield in the engine compartment near the
dash panel. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES/POWERTRAIN
CONTROL MODULE - DESCRIPTION).
²Sentry Key Immobilizer Module- The Sentry
Key Immobilizer Module (SKIM) is located beneath
the steering column shrouds on the right side of the
steering column near the ignition lock cylinder hous-
ing. (Refer to 8 - ELECTRICAL/ELECTRONIC CON-
TROL MODULES/SENTRY KEY IMMOBILIZER
MODULE - DESCRIPTION).
²Sentry Key Transponder- The Sentry Key
transponder is molded into the head of the ignition
key, and concealed by a gray molded rubber cap.
(Refer to 8 - ELECTRICAL/VEHICLE THEFT SECU-
RITY/TRANSPONDER KEY - DESCRIPTION).
²SKIS Indicator- The SKIS indicator is located
in the ElectroMechanical Instrument Cluster (EMIC)
on the instrument panel in front of the driver side
front seat. (Refer to 8 - ELECTRICAL/INSTRU-
MENT CLUSTER/SPEED CONTROL INDICATOR -
DESCRIPTION).
OPERATION
The Vehicle Theft Security System (VTSS) is
divided into two basic subsystems: Vehicle Theft
Alarm (VTA) and Sentry Key Immobilizer System
(SKIS). Following are paragraphs that briefly
describe the operation of each of these two sub-
systems.
VEHICLE THEFT ALARM The Body Control Mod-
ule (BCM) is used on this model to control and inte-
grate many of the electronic functions and features
included in the Vehicle Theft Alarm (VTA). The BCM
receives hard wired inputs indicating the status of
the door ajar switches, the door cylinder lock
switches, the ignition switch, the tailgate ajar switch,
the tailgate cylinder lock switch, the flip-up glass
ajar switch, the power lock switches and, in vehicles
built for certain markets where it is required, the
hood ajar switch. The programming in the BCM
allows it to process the information from all of these
inputs and send control outputs to energize or de-en-
KJVEHICLE THEFT SECURITY 8Q - 3
VEHICLE THEFT SECURITY (Continued)