cable JEEP LIBERTY 2002 KJ / 1.G Workshop Manual
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Page 679 of 1803

²The VSS signal decreases at a rate of 10 mph
per second (indicates that the vehicle may have
decelerated at an extremely high rate)
²If the actual speed is not within 20 mph of the
set speed
The previous disengagement conditions are pro-
grammed for added safety.
Once the speed control has been disengaged,
depressing the ACCEL switch restores the vehicle to
the target speed that was stored in the PCM's RAM.
NOTE: Depressing the OFF switch will erase the set
speed stored in the PCM's RAM.
If, while the speed control is engaged, the driver
wishes to increase vehicle speed, the PCM is pro-
grammed for an acceleration feature. With the
ACCEL switch held closed, the vehicle accelerates
slowly to the desired speed. The new target speed is
stored in the PCM's RAM when the ACCEL switch is
released. The PCM also has a9tap-up9feature in
which vehicle speed increases at a rate of approxi-
mately 2 mph for each momentary switch activation
of the ACCEL switch.
The PCM also provides a means to decelerate with-
out disengaging speed control. To decelerate from an
existing recorded target speed, depress and hold the
COAST switch until the desired speed is reached.
Then release the switch. The ON, OFF switch oper-
ates two components: the PCM's ON, OFF input, and
the battery voltage to the brake switch, which powers
the speed control servo.
Multiplexing
The PCM sends out 5 volts through a fixed resistor
and monitors the voltage change between the fixed
resistor and the switches. If none of the switches are
depressed, the PCM will measure 5 volts at the sen-
sor point (open circuit). If a switch with no resistor is
closed, the PCM will measure 0 volts (grounded cir-
cuit). Now, if a resistor is added to a switch, then the
PCM will measure some voltage proportional to the
size of the resistor. By adding a different resistor to
each switch, the PCM will see a different voltage
depending on which switch is pushed.
Another resistor has been added to the 'at rest cir-
cuit' causing the PCM to never see 5 volts. This was
done for diagnostic purposes. If the switch circuit
should open (bad connection), then the PCM will see
the 5 volts and know the circuit is bad. The PCM will
then set an open circuit fault.
REMOVAL
WARNING: BEFORE ATTEMPTING TO DIAGNOSE,
REMOVE OR INSTALL ANY AIRBAG SYSTEM OR
RELATED STEERING WHEEL AND STEERING COL-
UMN COMPONENTS YOU MUST FIRST DISCON-
NECT AND ISOLATE THE NEGATIVE (GROUND)
BATTERY CABLE. WAIT 2 MINUTES FOR SYSTEM
CAPACITOR TO DISCHARGE BEFORE FURTHER
SYSTEM SERVICE. FAILURE TO DO SO COULD
RESULT IN ACCIDENTAL DEPLOYMENT AND POS-
SIBLE PERSONAL INJURY.
(1) Disconnect and isolate negative battery cable
from battery.
(2) Remove airbag module. Refer to Restraint Sys-
tems.
(3) Unplug electrical connector (Fig. 7).
(4) Remove speed control switch mounting screw
(Fig. 7) and remove switch from steering wheel.
INSTALLATION
(1) Position switch to steering wheel.
(2) Install switch mounting screw and tighten.
Refer to torque specifications.
(3) Plug electrical connector into switch.
(4) Install airbag module. Refer to Restraint Sys-
tems.
(5) Connect negative battery cable to battery.
Fig. 7 SPEED CONTROL SWITCH
1 - SWITCH
2 - SCREW
3 - ELECTRICAL CONNECTOR
8P - 6 SPEED CONTROLKJ
SWITCH (Continued)
Page 687 of 1803

DIAGNOSIS AND TESTING - VEHICLE THEFT
SECURITY SYSTEM
The Vehicle Theft Security System (VTSS) is
divided into two basic subsystems: Vehicle Theft
Alarm (VTA) and Sentry Key Immobilizer System
(SKIS). Following are the recommended procedures
for diagnosis and testing of each of these two sub-
systems.
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.
VEHICLE THEFT ALARM
Models equipped with the Rest-Of-World (ROW)
premium version of the Vehicle Theft Alarm (VTA)
provide some preliminary diagnostic feedback by illu-minating the security indicator located in the Elec-
troMechanical Instrument Cluster (EMIC). If the
security indicator illuminates with the ignition
switch in the On position, it indicates that there is a
communication problem between the Intrusion
Transceiver Module (ITM) and the Body Control
Module (BCM), or between the ITM and the siren
module. The BCM will also turn on the security indi-
cator if it receives a message from the ITM indicating
that the ITM has stored a Diagnostic Trouble Code
(DTC) for a siren module fault.
The hard wired circuits and components of the
VTA may be diagnosed and tested using conventional
diagnostic tools and procedures. However, conven-
tional diagnostic methods may not prove conclusive
in the diagnosis of the Body Control Module (BCM),
the ElectroMechanical Instrument Cluster (EMIC),
the Intrusion Transceiver Module (ITM), or the Pro-
grammable Communications Interface (PCI) data bus
network. The most reliable, efficient, and accurate
means to diagnose the BCM, the EMIC, the ITM,
and the PCI data bus network inputs and outputs
related to the VTA requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation.
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.
8Q - 6 VEHICLE THEFT SECURITYKJ
VEHICLE THEFT SECURITY (Continued)
Page 688 of 1803

SENTRY KEY IMMOBILIZER SYSTEM
SENTRY KEY IMMOBILIZER SYSTEM DIAGNOSIS
CONDITION POSSIBLE CAUSES CORRECTION
SKIS INDICATOR FAILS TO
LIGHT DURING BULB TEST1. SKIS indicator faulty. 1. Test and replace the instrument cluster as
required.
2. Fuse faulty. 2. Test and replace the SKIM fused B(+) and
fused ignition switch output (run-start) fuses in the
Junction Block (JB) as required.
3. Ground circuit faulty. 3. Test and repair the SKIM ground circuit as
required.
4. Fused B(+) circuit faulty. 4. Test and repair the SKIM fused B(+) circuit as
required.
5. Fused ignition switch
output circuit faulty.5. Test and repair the SKIM fused ignition switch
output (run-start) circuit as required.
SKIS INDICATOR FLASHES
WHEN IGNITION SWITCH IS
TURNED TO9ON9
POSITION1. Invalid key in ignition
switch lock cylinder.1. Replace the key with a known valid key.
2. Key-related fault. 2. Use a DRBIIITscan tool to diagnose the
key-related fault. Refer to the appropriate
diagnostic information.
SKIS INDICATOR LIGHTS
SOLID FOLLOWING BULB
TEST1. SKIS system malfunction/
fault detected.1. Use a DRBIIITscan tool to diagnose the SKIS.
Refer to the appropriate diagnostic information.
2. SKIS system inoperative. 2. Use a DRBIIITscan tool to diagnose the SKIS.
Refer to the appropriate diagnostic information.
SKIS INDICATOR FAILS TO LIGHT DURING BULB TEST
If the Sentry Key Immobilizer System (SKIS) indi-
cator in the instrument cluster fails to illuminate for
about three seconds after the ignition switch is
turned to the On position (bulb test), perform the
instrument cluster actuator test. (Refer to 8 - ELEC-
TRICAL/INSTRUMENT CLUSTER - DIAGNOSIS
AND TESTING). If the SKIS indicator still fails to
light during the bulb test, a wiring problem resulting
in the loss of battery current or ground to the Sentry
Key Immobilizer Module (SKIM) should be sus-
pected, and the following procedure should be used
for diagnosis. Refer to the appropriate wiring infor-
mation. The wiring information includes wiring dia-
grams, proper wire and connector repair procedures,
details of wire harness routing and retention, connec-
tor pin-out information and location views for the
various wire harness connectors, splices and grounds.
NOTE: The following tests may not prove conclu-
sive in the diagnosis of this system. The most reli-
able, efficient, and accurate means to diagnose the
Sentry Key Immobilizer System requires the use of
a DRBIIITscan tool. Refer to the appropriate diag-
nostic information.(1) Check the fused B(+) fuse (Fuse 33 - 10
ampere) in the Junction Block (JB). If OK, go to Step
2. If not OK, repair the shorted circuit or component
as required and replace the faulty fuse.
(2) Check for battery voltage at the fused B(+) fuse
(Fuse 33 - 10 ampere) in the JB. If OK, go to Step 3.
If not OK, repair the open B(+) circuit between the
JB and the battery as required.
(3) Check the fused ignition switch output (run-
start) fuse (Fuse 15 - 10 ampere) in the JB. If OK, go
to Step 4. If not OK, repair the shorted circuit or
component as required and replace the faulty fuse.
(4) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-start) fuse (Fuse 15 - 10 ampere) in the
JB. If OK, go to Step 5. If not OK, repair the open
fused ignition switch output (run-start) circuit
between the JB and the ignition switch as required.
(5) Disconnect and isolate the battery negative
cable. Disconnect the instrument panel wire harness
connector for the Sentry Key Immobilizer Module
(SKIM) from the SKIM connector receptacle. Check
for continuity between each of the two ground circuit
cavities of the instrument panel wire harness connec-
tor for the SKIM and a good ground. There should be
KJVEHICLE THEFT SECURITY 8Q - 7
VEHICLE THEFT SECURITY (Continued)
Page 689 of 1803

continuity. If OK, go to Step 6. If not OK, repair the
open ground circuit(s) to ground (G202) as required.
(6) Reconnect the battery negative cable. Check for
battery voltage at the fused B(+) circuit cavity of the
instrument panel wire harness connector for the
SKIM. If OK, go to Step 7. If not OK, repair the open
fused B(+) circuit between the SKIM and the JB as
required.
(7) Turn the ignition switch to the On position.
Check for battery voltage at the fused ignition switch
output (run-start) circuit cavity of the instrument
panel wire harness connector for the SKIM. If OK,
use a DRBIIItscan tool to complete the diagnosis of
the SKIS. Refer to the appropriate diagnostic infor-
mation. If not OK, repair the open fused ignition
switch output (run-start) circuit between the SKIM
and the JB as required.
SKIS INDICATOR FLASHES UPON IGNITION ªONº OR
LIGHTS SOLID FOLLOWING BULB TEST
A SKIS indicator that flashes following the ignition
switch being turned to the On position indicates that
an invalid key has been detected, or that a key-re-
lated fault has been set. A SKIS indicator that lights
solid following a successful bulb test indicates that
the SKIM has detected a system malfunction or that
the SKIS is inoperative. In either case, fault informa-
tion will be stored in the SKIM memory. For retrieval
of this fault information and further diagnosis of the
SKIS, the PCI data bus, the SKIM electronic mes-
sage outputs to the instrument cluster that control
the SKIS indicator and chime, or the electronic mes-
sage inputs and outputs between the SKIM and the
Powertrain Control Module (PCM) that control
engine operation, a DRBIIItscan tool is required.
Refer to the appropriate diagnostic information. Fol-
lowing are preliminary troubleshooting guidelines to
be followed during diagnosis using a DRBIIItscan
tool:
(1) Using the DRBIIItscan tool, read and record
the faults as they exist in the SKIM when you first
begin your diagnosis of the vehicle. It is important to
document these faults because the SKIM does not
differentiate between historical faults (those that
have occurred in the past) and active faults (those
that are currently present). If this problem turns out
to be an intermittent condition, this information may
become invaluable to your diagnosis.
(2) Using the DRBIIItscan tool, erase all of the
faults from the SKIM.
(3) Cycle the ignition switch to the Off position,
then back to the On position.
(4) Using the DRBIIItscan tool, read any faults
that are now present in the SKIM. These are the
active faults.(5) Using this active fault information, refer to the
proper procedure in the appropriate diagnostic infor-
mation for the specific additional diagnostic steps.
STANDARD PROCEDURE
STANDARD PROCEDURE - SKIS
INITIALIZATION
The Sentry Key Immobilizer System (SKIS) must
be initialized following a Sentry Key Immobilizer
Module (SKIM) replacement. SKIS initialization
requires the use of a DRBIIItscan tool. Initialization
will also require that you have access to the unique
four-digit PIN code that was assigned to the original
SKIM. The PIN codemustbe used to enter the
Secured Access Mode in the SKIM. This PIN number
may be obtained from the vehicle owner, from the
original vehicle invoice, or from the DaimlerChrysler
Customer Center. (Refer to 8 - ELECTRICAL/ELEC-
TRONIC CONTROL MODULES - STANDARD PRO-
CEDURE - PCM/SKIM PROGRAMMING).
NOTE: If a Powertrain Control Module (PCM) is
replaced on a vehicle equipped with the Sentry Key
Immobilizer System (SKIS), the unique Secret Key
data must be transferred from the Sentry Key
Immobilizer Module (SKIM) to the new PCM using
the PCM replacement procedure. This procedure
also requires the use of a DRBIIITscan tool and the
unique four-digit PIN code to enter the Secured
Access Mode in the SKIM. Refer to the appropriate
diagnostic information for the proper PCM replace-
ment procedures.
STANDARD PROCEDURE - SENTRY KEY
TRANSPONDER PROGRAMMING
All Sentry Keys included with the vehicle are pre-
programmed to work with the Sentry Key Immobi-
lizer System (SKIS) when it is shipped from the
factory. The Sentry Key Immobilizer Module (SKIM)
can be programmed to recognize up to a total of eight
Sentry Keys. When programming a blank Sentry Key
transponder, the key must first be cut to match the
ignition switch lock cylinder in the vehicle for which
it will be used. Once the additional or new key has
been cut, the SKIM must be programmed to recog-
nize it as a valid key. There are two possible methods
to program the SKIM to recognize a new or addi-
tional valid key, the Secured Access Method and the
Customer Learn Method. Following are the details of
these two programming methods.
8Q - 8 VEHICLE THEFT SECURITYKJ
VEHICLE THEFT SECURITY (Continued)
Page 691 of 1803

Theft Security System (VTSS) have a door cylinder
lock switch secured to the back of the key lock cylin-
der inside each front door (Fig. 2). The door cylinder
lock switch is a resistor multiplexed momentary
switch that is hard wired in series between the door
lock switch ground and right or left cylinder lock
switch mux circuits of the Body Control Module
(BCM) through the front door wire harness. The door
cylinder lock switches are driven by the key lock cyl-
inders and contain two internal resistors. One resis-
tor value is used for the Lock position, and one for
the Unlock position.
The door cylinder lock switches cannot be adjusted
or repaired and, if faulty or damaged, they must be
replaced.
OPERATION
The door cylinder lock switches are actuated by the
key lock cylinder when the key is inserted in the lock
cylinder and turned to the lock or unlock positions.
The door cylinder lock switch close a circuit between
the door lock switch ground circuit and the left or
right cylinder lock switch mux circuits through one of
two internal resistors for the Body Control Module
(BCM) when either front door key lock cylinder is in
the Lock, or Unlock positions. The BCM reads the
switch status through an internal pull-up, then uses
this information as an input for the Vehicle Theft
Security System (VTSS) operation.
The door cylinder lock switches and circuits can be
diagnosed using conventional diagnostic tools and
methods.
DIAGNOSIS AND TESTING - DOOR CYLINDER
LOCK SWITCH
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.
(1) Disconnect the door cylinder lock switch pigtail
wire connector from the door wire harness connector.
(2) Using a ohmmeter, check the switch resistance
checks between the two terminals in the door cylin-
der lock switch pigtail wire connector. Actuate the
switch by rotating the key in the door lock cylinder
to test for the proper resistance values in each of the
two switch positions, as shown in the Door Cylinder
Lock Switch Test table.
DOOR CYLINDER LOCK SWITCH TEST
Switch Position Resistance
( 10%)
Left Side Right Side
Lock (Clockwise) Unlock
(Counterclockwise)473 Ohms
Unlock
(Counterclockwise)Lock (Clockwise) 1.994 Kilohms
(3) If a door cylinder lock switch fails either of the
resistance tests, replace the faulty switch.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Remove the outside door handle unit from the
outer door panel. (Refer to 23 - BODY/DOOR -
FRONT/EXTERIOR HANDLE - REMOVAL).
(3) Remove the retainer clip from the pin on the
back of the door lock cylinder (Fig. 3).
(4) Remove the lock lever from the pin on the back
of the door lock cylinder.
(5) Remove the door cylinder lock switch from the
back of the lock cylinder.
INSTALLATION
(1) Position the door cylinder lock switch onto the
back of the lock cylinder with its pigtail wire harness
oriented toward the bottom (Fig. 3).
Fig. 3 Lock Cylinder Lever Retainer Remove/Install
1 - LEVER
2 - RETAINER
3 - LOCK CYLINDER
4 - SWITCH
5 - PLIERS
6 - OUTSIDE DOOR HANDLE
8Q - 10 VEHICLE THEFT SECURITYKJ
DOOR CYLINDER LOCK SWITCH (Continued)
Page 692 of 1803

(2) Position the lock lever onto the pin on the back
of the door lock cylinder with the lever oriented
toward the rear.
(3) Install the retainer clip onto the pin on the
back of the door lock cylinder. Be certain that the
center tab of the retainer is engaged in the retention
hole on the lock lever.
(4) Reinstall the outside door handle unit onto the
outer door panel. (Refer to 23 - BODY/DOOR -
FRONT/EXTERIOR HANDLE - INSTALLATION).
(5) Reconnect the battery negative cable.
HOOD AJAR SWITCH
DESCRIPTION
The hood ajar switch is a normally closed, single
pole momentary switch that is used only on vehicles
equipped with the Vehicle Theft Security System
(VTSS) for sale in certain markets where it is
required equipment (Fig. 4). This switch consists of a
molded plastic body with a molded plastic mounting
bezel. The switch body has an integral molded con-nector receptacle on the lower end, while the spring-
loaded switch plunger extends from the upper end.
Two external latches integral to the mounting bezel
lock the switch into a keyed mounting hole in the
stamped steel switch mounting bracket. The mount-
ing bracket is fastened with two screws to the right
inner fender shield near the fender ledge in the
engine compartment. A molded plastic striker with
an integral retainer and mounting tab is secured to
the underside of the hood panel inner reinforcement
to actuate the switch plunger as the hood panel is
closed (Fig. 5). A single take out of the headlamp and
dash wire harness connects the switch to the vehicle
electrical system. The switch receives a path to
ground at all times through another take out of the
headlamp and dash wire harness with an eyelet ter-
minal connector that is secured by a ground screw to
the left inner fender shield in the engine compart-
ment.
The hood ajar switch cannot be adjusted or
repaired and, if faulty or damaged, it must be
replaced. The hood ajar switch striker is not intended
for reuse. If the striker is removed from the hood
inner reinforcement for any reason, it must be
replaced with a new unit.
Fig. 4 Hood Ajar Switch
1 - INNER FENDER
2 - SCREW (2)
3 - BRACKET
4 - HOOD AJAR SWITCH
5 - WIRE HARNESS CONNECTOR
Fig. 5 Hood Ajar Switch Striker
1 - STRIKER
2-TAB
3 - INNER HOOD REINFORCEMENT
4 - RETAINER
KJVEHICLE THEFT SECURITY 8Q - 11
DOOR CYLINDER LOCK SWITCH (Continued)
Page 693 of 1803

OPERATION
The hood ajar switch is normally held open as the
spring-loaded switch plunger is depressed by the
striker on the hood panel when the hood panel is
closed and latched. When the hood is opened, the
spring-loaded switch plunger extends from the switch
body and the switch contacts are closed. The hood
ajar switch is connected in series between ground
and the hood ajar switch sense input of the Body
Control Module (BCM). The BCM uses an internal
resistor pull up to monitor the state of the hood ajar
switch contacts. The hood ajar switch can be diag-
nosed using conventional diagnostic tools and meth-
ods.
DIAGNOSIS AND TESTING - HOOD AJAR
SWITCH
Refer to the appropriate wiring information. The
wiring information includes wiring diagrams, proper
wire and connector repair procedures, details of wire
harness routing and retention, connector pin-out
information and location views for the various wire
harness connectors, splices and grounds.
(1) Disconnect the headlamp and dash wire har-
ness connector for the hood ajar switch from the
switch connector receptacle.
(2) Check for continuity between the two terminals
in the connector receptacle of the hood ajar switch.
There should be continuity with the switch plunger
extended, and no continuity with the switch plunger
depressed. If not OK, replace the faulty hood ajar
switch.
REMOVAL
(1) Unlatch and open the hood.
(2) Disconnect and isolate the battery negative
cable.
(3) From the top of the hood ajar switch mounting
bracket, squeeze the two switch latch tabs together
and pull the switch upward (Fig. 6).
(4) Pull the hood ajar switch up through the hole
in the mounting bracket far enough to access and
disconnect the headlamp and dash wire harness con-
nector for the hood ajar switch from the switch con-
nector receptacle.(5) Remove the hood ajar switch from the mount-
ing bracket.
INSTALLATION
(1) Position the hood ajar switch near the hole in
the mounting bracket (Fig. 6).
(2) Reconnect the headlamp and dash wire harness
connector for the hood ajar switch to the switch con-
nector receptacle.
(3) From the top of the hood ajar switch mounting
bracket, use hand pressure to press the switch down-
ward into the mounting bracket until the latch tabs
lock it into place.
(4) Reconnect the battery negative cable.
(5) Close and latch the hood.
Fig. 6 Hood Ajar Switch Remove/Install
1 - INNER FENDER
2 - SCREW (2)
3 - BRACKET
4 - HOOD AJAR SWITCH
5 - WIRE HARNESS CONNECTOR
8Q - 12 VEHICLE THEFT SECURITYKJ
HOOD AJAR SWITCH (Continued)
Page 696 of 1803

electronic circuitry of the ITM which includes a
microprocessor, and an ultrasonic receive transducer.
A molded plastic connector receptacle containing six
terminal pins that is soldered to a small circuit board
and extends through a clearance hole in the left front
corner of the ITM housing, and an ultrasonic trans-
mit transducer housing extends from the center of
the right side of the ITM housing. Both the transmit
transducer on the right side of the module and the
receive transducer on the ITM circuit board are
aimed through two small round holes in the sight
shield of the trim cover. The ITM is connected to the
vehicle electrical system by a dedicated take out and
connector of the overhead wire harness that is inte-
gral to the headliner.
The ITM unit cannot be adjusted or repaired and,
if faulty or damaged, it must be replaced. The ITM is
serviced as a unit with the trim cover.
OPERATION
The microprocessor in the Intrusion Transceiver
Module (ITM) contains the motion sensor logic cir-
cuits and controls all of the features of the premium
version of the Vehicle Theft Alarm (VTA). The ITM
uses On-Board Diagnostics (OBD) and can communi-
cate with other electronic modules in the vehicle as
well as with the DRBIIItscan tool using the Pro-
grammable Communications Interface (PCI) data bus
network. This method of communication is used by
the ITM to communicate with the Body Control Mod-
ule (BCM) and for diagnosis and testing through the
16-way data link connector located on the driver side
lower edge of the instrument panel. The ITM also
communicates with the alarm siren over a dedicated
serial bus circuit.
The ITM microprocessor continuously monitors
inputs from its on-board motion sensor circuitry as
well as inputs from the BCM and the alarm siren
module. The on-board ITM motion sensor circuitry
transmits ultrasonic signals into the vehicle cabin
through a transmit transducer, then listens to the
returning signals as the bounce off of objects in the
vehicle interior. If an object is moving in the interior,
a detection circuit in the ITM senses this movement
through the modulation of the returning ultrasonic
signals that occurs due to the Doppler effect. The
motion detect function of the ITM can be disabled by
depressing the ªLockº button on the Remote Keyless
Entry (RKE) transmitter three times within fifteen
seconds, while the security indicator is still flashing
rapidly. The ITM will signal the alarm siren module
to provide a single siren ªchirpº as an audible confir-
mation that the motion sensor function has been dis-
abled.
If movement is detected, the ITM sends an elec-
tronic message to the BCM over the PCI data bus toflash the exterior lighting and sends an electronic
message to the alarm siren module over a dedicated
serial bus line to sound the siren. When the BCM
detects a breach in the perimeter protection through
a door, tailgate, flip-up glass, or hood ajar switch
input, it sends an electronic message to the ITM and
the ITM sends an electronic message to the BCM
over the PCI data bus to flash the exterior lighting
and sends an electronic message to the alarm siren
module over a dedicated serial bus line to sound the
siren. The ITM also monitors inputs from the alarm
siren module for siren battery or siren input/output
circuit tamper alerts, and siren battery condition
alerts, then sets active and stored Diagnostic Trouble
Codes (DTC) for any monitored system faults it
detects. 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 ITM. If a fault
does not recur for fifty ignition cycles, the ITM will
automatically erase the stored DTC.
The ITM is connected to the vehicle electrical sys-
tem through a dedicated take out and connector of
the overhead wire harness. The ITM receives battery
current on a fused B(+) circuit through a fuse in the
Junction Block (JB), and receives ground through a
ground circuit and take out of the body wire harness.
This ground take out has a single eyelet terminal
connector that is secured by a ground screw to the
base of the left D-pillar behind the quarter trim
panel. These connections allow the ITM to remain
operational, regardless of the ignition switch position.
The hard wired inputs and outputs for the ITM may
be diagnosed and tested using conventional diagnos-
tic tools and procedures. However, conventional diag-
nostic methods will not prove conclusive in the
diagnosis of the ITM, the PCI data bus network, or
the electronic message inputs to and outputs from
the ITM. The most reliable, efficient, and accurate
means to diagnose the ITM, the PCI data bus net-
work, and the electronic message inputs to and out-
puts from the ITM requires the use of a DRBIIIt
scan tool. Refer to the appropriate diagnostic infor-
mation.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) While pulling downward lightly on either rear
corner of the Intrusion Transceiver Module (ITM)
trim cover, insert a small thin-bladed screwdriver
through each of the service holes on the rear edge of
the trim cover to depress and release the two inte-
gral rear latch features of the module from the
mounting bracket above the headliner (Fig. 11).
(3) Pull the ITM trim cover rearward far enough
to disengage the two integral front latch features of
KJVEHICLE THEFT SECURITY 8Q - 15
INTRUSION TRANSCEIVER MODULE (Continued)
Page 697 of 1803

the module from the mounting bracket above the
headliner.
(4) Pull the ITM and trim cover down from the
headliner far enough to access and disconnect the
overhead wire harness connector for the ITM from
the module connector receptacle.
(5) Remove the ITM from the headliner.
INSTALLATION
(1) Position the Intrusion Transceiver Module
(ITM) to the headliner.
(2) Reconnect the overhead wire harness connector
for the ITM to the module connector receptacle.
(3) Align the two integral front latch features of
the ITM with the two front latch receptacles of the
mounting bracket above the headliner (Fig. 12).
(4) Push the ITM trim cover forward far enough to
insert the two integral rear latch features of the
module into the two rear latch receptacles of the
mounting bracket above the headliner.
(5) Push upward firmly and evenly on the rear
edge of the ITM trim cover until the two integral
rear latch features of the module are engaged in the
latch receptacles of the mounting bracket above the
headliner.
(6) Reconnect the battery negative cable.
NOTE: If the Intrusion Transceiver Module (ITM) has
been replaced with a new unit, the new ITM MUST
be initialized before the Vehicle Theft Security Sys-
tem can operate as designed. The use of a DRBIIIT
scan tool is required to initialize the ITM. Refer to
the appropriate diagnostic information.
SIREN
DESCRIPTION
An alarm siren module is part of the Rest-Of-World
(ROW) premium version of the Vehicle Theft Alarm
(VTA) in the Vehicle Theft Security System (VTSS)
(Fig. 13). The ROW premium version of the VTA is
only available in vehicles built for certain markets,
where the additional features offered by this system
are required. The alarm siren module is located in
Fig. 11 Intrusion Transceiver Module Remove
1 - SMALL SCREWDRIVER
2 - HEADLINER
3 - SERVICE HOLES
4 - ITM
Fig. 12 Intrusion Transceiver Module Mounting
Bracket
1 - STAMPED NUT (2)
2 - MOUNTING BRACKET
3 - HEADLINER
4 - LATCH RECEPTACLES (4)
Fig. 13 Siren Module
1 - BRACKET
2 - NUT (3)
3 - CONNECTOR RECEPTACLE
4 - SIREN MODULE
8Q - 16 VEHICLE THEFT SECURITYKJ
INTRUSION TRANSCEIVER MODULE (Continued)
Page 698 of 1803

the engine compartment, on the front extension of
the right front wheel house panel below and behind
the right headlamp. This unit is designed to provide
the audible alert requirements for the ROW premium
VTA.
The alarm siren module consists of microprocessor-
based electronic control circuitry, the siren, and a
nickel metal hydride backup battery. All of the alarm
module components are protected and sealed within
a black molded plastic housing. A stamped steel
mounting bracket is secured to the module with
three stud plates and nuts that fit into slotted holes
at the top and each side of the bracket. The front
surface of the bracket features a tightly grouped
series of small holes that serves as an outlet for the
audible output of the alarm siren. The bottom of the
mounting bracket is bent at a right angle and has an
integral locating tab feature. Two mounting holes in
the horizontal surface of the bracket are used to
secure the alarm siren module to the wheel house
extension with two screws. An integral connector
receptacle extends forward from the upper left corner
of the alarm siren housing, and connects the unit to
the vehicle electrical system through a dedicated
take out and connector of the headlamp and dash
wire harness.
The alarm siren module cannot be repaired or
adjusted and, if faulty or damaged, it must be
replaced.
OPERATION
The microprocessor within the alarm siren module
performs the tasks required to provide the siren unit
features and functions based upon internal program-
ming and electronic arm and disarm message inputs
received from the Intrusion Transceiver Module
(ITM) over a dedicated serial bus communication cir-
cuit. The alarm siren module will self-detect prob-
lems with its internal and external power supply and
communication circuits, then send electronic mes-
sages indicating the problem to the ITM upon receiv-
ing a request from the ITM. The ITM will store a
Diagnostic Trouble Code (DTC) for a detected alarm
siren module fault that can be retrieved with the
DRBIIItscan tool over the Programmable Communi-
cations Interface (PCI) data bus network through the
16-way data link connector located on the driver side
lower edge of the instrument panel.
When the Rest-Of-World (ROW) premium version
of the Vehicle Theft Alarm (VTA) is armed, the alarm
siren module microprocessor continuously monitors
inputs from the ITM for messages to sound its inter-
nal siren and enters its auto-detect mode. While in
the auto-detect mode, if the alarm siren module
detects that its power supply or communication cir-
cuits are being tampered with or have been sabo-taged, it will sound an alarm and continue to operate
through its on-board backup battery. If the arm siren
module is in its disarmed mode when its power sup-
ply or communication circuits are interrupted, the
siren will not sound. The alarm module will also
notify the ITM when the backup battery requires
charging, and the ITM will send a message that will
allow the backup battery to be charged through the
battery current and ground circuits to the alarm
module only when the ignition switch is in the On
position and the engine is running. This will prevent
the charging of the alarm backup battery from
depleting the charge in the main vehicle battery
while the vehicle is not being operated.
The alarm siren module receives battery current
on a fused B(+) circuit through a fuse in the Power
Distribution Center (PDC), and receives ground
through a ground circuit and take out of the head-
lamp and dash wire harness. This ground take out
has a single eyelet terminal connector that is secured
by a ground screw to the left inner fender shield in
the engine compartment. These connections allow the
alarm siren module to remain operational, regardless
of the ignition switch position. The hard wired inputs
and outputs for the alarm siren module may be diag-
nosed and tested using conventional diagnostic tools
and procedures. However, conventional diagnostic
methods will not prove conclusive in the diagnosis of
the internal circuitry or the backup battery of the
alarm siren module, the ITM, the serial bus commu-
nication line, or the electronic message inputs to and
outputs from the alarm siren module. The most reli-
able, efficient, and accurate means to diagnose the
alarm siren module, the ITM, the serial bus commu-
nication line, and the electronic message inputs to
and outputs from the alarm siren module requires
the use of a DRBIIItscan tool. Refer to the appro-
priate diagnostic information.
REMOVAL
(1) Disconnect and isolate the battery negative
cable.
(2) Disconnect the headlamp and dash wire har-
ness connector for the alarm siren module from the
module connector receptacle (Fig. 14).
(3) Remove the two screws that secure the alarm
siren module to the front extension of the right front
wheel house panel.
(4) Remove the alarm siren module from the front
extension of the right front wheel house panel.
INSTALLATION
(1) Position the alarm siren module onto the front
extension of the right front wheel house panel (Fig.
14).
KJVEHICLE THEFT SECURITY 8Q - 17
SIREN (Continued)