Jeep Liberty KJ. Manual - part 301

identifies the key as valid, the SKREEM sends a valid key message to the PCM over the PCI data bus. If the
response received identifies the key as invalid, or if no response is received from the key transponder, the SKREEM
sends an invalid key message to the PCM. The PCM will enable or disable engine operation based upon the status
of the SKREEM messages. It is important to note that the default condition in the PCM is an invalid key; therefore,
if no message is received from the SKREEM by the PCM, the engine will be disabled and the vehicle immobilized
after two seconds of running.

The SKREEM also sends SKIS indicator status messages to the BCM over the PCI data bus to tell the BCM how
to operate the security indicator in the ElectroMechanical Instrument Cluster (EMIC). This indicator status message
tells the BCM to turn the indicator on for about three seconds each time the ignition switch is turned to the ON
position as a bulb test. After completion of the bulb test, the SKREEM sends indicator status messages to the BCM
to turn the indicator off, turn the indicator on, or to flash the indicator on and off. If the security indicator flashes
upon ignition ON or stays on solid after the bulb test, it signifies a SKIS fault.

If the SKREEM detects a system malfunction or if the SKIS has become inoperative, the security indicator will stay
on solid. If the SKREEM detects an invalid key or if a key transponder-related fault exists, the security indicator will
flash. If the vehicle is equipped with the Customer Learn transponder programming feature, the SKREEM will also
send messages to the BCM to flash the security indicator and to generate a single audible chime whenever the
Customer Learn programming mode is being utilized. (Refer to 8 - ELECTRICAL/VEHICLE THEFT SECURITY -
STANDARD PROCEDURE - SENTRY KEY TRANSPONDER PROGRAMMING).

The SKIS performs a self-test each time the ignition switch is turned to the On position, and will store fault infor-
mation in the form of a Diagnostic Trouble Code (DTC) in SKREEM memory if a system malfunction is detected.
The SKREEM can be diagnosed, and any stored DTC can be retrieved using a diagnostic scan tool. Refer to the
appropriate diagnostic information.

REMOVAL

WARNING: To avoid personal injury or death, on vehicles equipped with airbags, disable the supplemental
restraint system before attempting any steering wheel, steering column, airbag, occupant classification sys-
tem, seat belt tensioner, impact sensor, or instrument panel component diagnosis or service. Disconnect
and isolate the battery negative (ground) cable, then wait two minutes for the system capacitor to discharge
before performing further diagnosis or service. This is the only sure way to disable the supplemental
restraint system. Failure to take the proper precautions could result in accidental airbag deployment.

1. Disconnect and isolate the negative battery cable.

2. If the vehicle is equipped with a tilt steering col-

umn, move the tilt steering column to the fully low-
ered position and leave the tilt release lever in the
released (down) position.

3. From below the steering column (2), remove the

two screws (6) that secure the lower shroud (5) to
the upper shroud (1).

4. Using hand pressure, push gently inward on both

sides of the upper shroud near the parting line of
the lower shroud to release the snap features that
secure the two shroud halves to each other.

5. Remove both the upper and lower shrouds from

the steering column.

6. Disconnect the wire harness connector (3) from the

Sentry Key REmote Entry Module (SKREEM) (4).

7. The SKREEM mounting bracket features a clip that

secures the module to the right lower flange of the
steering column jacket. Pull downward on the con-
nector end of the SKREEM mounting bracket to
release this clip from the steering column.

8. Rotate the SKREEM and its mounting bracket downwards and then to the side away from the steering column to

disengage the antenna ring from around the ignition lock cylinder housing (7).

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VEHICLE THEFT SECURITY - SERVICE INFORMATION

9. Lift the multi-function switch upward off of the upper steering column housing far enough to remove the SKREEM

antenna ring formation from between the ignition key release button and the multi-function switch housing.

10. Remove the SKREEM from the steering column.

INSTALLATION

1. Position the SKREEM (4) to the right side of the

steering column (2).

2. Lift the multi-function switch upward off of the

upper steering column housing far enough to insert
the SKREEM antenna ring formation between the
ignition key release button and the multi-function
switch housing.

3. Slide the SKREEM antenna ring around the ignition

switch lock cylinder housing (7), then rotate the
SKREEM and its mounting bracket upwards and
toward the steering column.

4. Align the SKREEM mounting bracket clip with the

right lower flange of the steering column jacket
and, push upward firmly and evenly on the connec-
tor end of the module mounting bracket to engage
this clip with the steering column.

5. Reconnect the wire harness connector (3) to the

SKREEM.

6. Position both the upper (1) and lower shrouds (5)

onto the steering column.

7. Align the snap features on the lower shroud with

the receptacles in the upper shroud and apply hand pressure to snap them together.

8. From below the steering column, install and tighten the two screws (6) that secure the lower shroud to the upper

shroud. Tighten the screws to 2 N·m (18 in. lbs.).

9. If the vehicle is equipped with a tilt steering column, move the column to the fully raised position and secure it

in place by moving the tilt release lever back to the locked (up) position.

10. Reconnect the negative battery cable.

NOTE: If the Sentry Key REmote Entry Module (SKREEM) is replaced with a new unit, a diagnostic scan tool
MUST be used to initialize the new SKREEM and to program at least two Sentry Key transponders before
the vehicle can be operated. (Refer to 8 - ELECTRICAL/VEHICLE THEFT SECURITY - STANDARD PROCE-
DURE - SKIS INITIALIZATION).

VEHICLE THEFT SECURITY - SERVICE INFORMATION

8Q - 81

SIREN

DESCRIPTION

An alarm siren module (2) is part of the export pre-
mium version of the Vehicle Theft Alarm (VTA) in the
Vehicle Theft Security System (VTSS). The export pre-
mium 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 the engine compartment, on the
front extension of the right front wheel house panel
below and behind the right headlamp. This assembly
is designed to provide the audible alert requirements
for the export 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 molded plastic hous-
ing. A stamped steel mounting bracket (3) is secured to the module with three stud plates and nuts (1) that fit into
slotted holes at the top and each side of the bracket. Two mounting holes in the horizontal surface of the bracket
are used to secure the alarm siren module to the wheel house extension with screws. A connector receptacle (4)
extends forward from the alarm siren housing, and connects the module to the vehicle electrical system through a
dedicated take out of the headlamp and dash wire harness.

The alarm siren module cannot be repaired or adjusted and, if inoperative or damaged, it must be replaced.

OPERATION

The microprocessor within the alarm siren module performs the tasks required to provide the siren features and
functions based upon internal programming and electronic arm and disarm message inputs received from the Intru-
sion Transceiver Module (ITM) over a dedicated serial bus communication circuit. Upon receiving a request from the
ITM, the alarm siren module will self-detect problems with its internal and external power supply and communication
circuits, then send electronic messages indicating the problem to the ITM. The ITM will store a Diagnostic Trouble
Code (DTC) for a detected alarm siren module fault that can be retrieved with a diagnostic scan tool over the Pro-
grammable Communications Interface (PCI) data bus through the 16-way data link connector located on the driver
side lower edge of the instrument panel.

When the export premium version of the Vehicle Theft Alarm (VTA) is armed, the alarm siren module microproces-
sor continuously monitors inputs from the ITM for messages to sound its internal siren and to enter its auto-detect
mode. While in the auto-detect mode, if the alarm siren module detects that its power supply or communication
circuits are being tampered with or have been sabotaged, it will sound an alarm and continue to operate through its
on-board backup battery. If the alarm siren module is in its disarmed mode when its power supply 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 voltage 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 recharging 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 voltage through a fuse in the Power Distribution Center (PDC), and
receives ground through a ground location on the left inner fender shield in the engine compartment. These con-
nections 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 diagnosed 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 communication line, or the

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VEHICLE THEFT SECURITY - SERVICE INFORMATION

electronic message inputs to and outputs from the alarm siren module. The most reliable, efficient, and accurate
means to diagnose the alarm siren module, the ITM, the serial bus communication line, and the electronic message
inputs to and outputs from the alarm siren module requires the use of a diagnostic scan tool. Refer to the appro-
priate diagnostic information.

REMOVAL

1. Disconnect and isolate the battery negative cable.

2. Disconnect the wire harness connector (3) from the

connector receptacle of the alarm siren module (2).

3. Remove the two screws (1) 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 (2) onto the front

extension of the right front wheel house panel.

2. Install and tighten the two screws (1) that secure

the alarm siren module to the front extension of the
right front wheel house panel. Tighten the screws
to 6 N·m (50 in. lbs.).

3. Reconnect the wire harness connector (3) for the

alarm siren module.

4. Reconnect the battery negative cable.

NOTE:

the

alarm

siren

module

has

been

replaced with a new unit, the new unit MUST be
configured in the Intrusion Transceiver Module
(ITM) before the Vehicle Theft Security System can
operate as designed. The use of a diagnostic scan
tool is required to configure the alarm siren mod-
ule settings in the ITM. Refer to the appropriate
diagnostic information.

VEHICLE THEFT SECURITY - SERVICE INFORMATION

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