is available as an option and includes interior moni-
toring, anti-tow away protection and rear window
monitoring based on the heater wires. The alarm is
automatically activated when the central locking sys-
tem is operated.

The alarm will sound when any of the following

occur:

• A door is opened

• A door is unlocked from inside the vehicle

• The hood is opened

• The vehicle is raised at the front or rear

• The trailer wire harness is disconnected

• Movements inside the vehicle

• The central locking is unlocked by a key at any

other door than the driver’s door

The alarm is functional about 30 seconds after the

vehicle is locked using the RKE transmitter or the
key in the driver’s door. Activation is indicated by the
indicator lights flashing three times and the warning
lamp flashing in the switch. If persons or animals
remain in the locked vehicle, the operator should
switch off the interior monitor to avoid a false alarm.

OPERATION

The anti-theft alarm is activated/deactivated by

locking/unlocking the vehicle with the remote trans-
mitter or with the key at the driver’s door. The key
must be held in the locking position for more than
two seconds. Activation is indicated by the turn sig-
nal lights flashing once. Unlocking the vehicle at one
of the other doors will trigger an alarm.

The interior monitoring system included in the

anti-theft alarm is based on ultrasonics and triggers

an alarm if an object intrudes the interior of the
vehicle or if any movement is detected inside the
vehicle. For proper and effective protection, all win-
dows and the sunroof must be closed.

To switch off the interior monitoring system and /

or the anti-tow away protection, a switch with LED
indicator light is provided in the switch panel. An
alarm button enables the operator to trigger an
alarm manually and to lock all doors if they are
closed. Triggering an alarm makes the horn sound
and the turn signals flash until the alarm is switched
off.

The anti-theft alarm control unit includes a gradi-

ent indicator as anti-tow away protection. The gradi-
ent indicator triggers an audible and visual alarm if
the vehicle is lifted (to tow away or to remove the
wheels). The alarm remains effective even if the bat-
tery is disconnected as the horn is powered by its
own battery. The interior monitoring system should
be switched off if people and/or animals are left in
the vehicle.

DIAGNOSIS AND TESTING - VEHICLE THEFT
SECURITY

Any diagnosis of the Vehicle Theft Security

system should begin with the use of a diagnos-
tic scan tool. Refer to the appropriate diagnos-
tic information.

INTRUSION SENSOR

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Insert the tip of a small flat-bladed screwdriver

into the notch on one edge of the dome lamp/intru-
sion sensor unit housing to depress the retainer clip

VEHICLE THEFT SECURITY

8Q - 1

and pull that edge of the lamp away from its mount-
ing location (Fig. 1).

(3) Pull the dome lamp/intrusion sensor unit from

its mounting location far enough to access and dis-
connect the vehicle wire harness from the lamp con-
nector receptacle.

(4) Remove the dome lamp/intrusion sensor unit

from its mounting location.

INSTALLATION

(1) Position the dome lamp/intrusion sensor unit to

its mounting location.

(2) Reconnect the vehicle wire harness connector

to the dome lamp/intrusion sensor unit connector
receptacle.

(3) Position the edge of the dome lamp/intrusion

sensor unit housing opposite from the retainer clip
into the mounting hole.

(4) Push firmly and evenly on the notched edge of

the dome lamp/intrusion sensor unit housing until
the retainer clip latches into place.

(5) Connect the battery negative cable.

SECURITY SYSTEM MODULE

REMOVAL

(1) Disconnect and isolate the battery negative

cable.

(2) Remove driver seat cushion.
(3) Remove mounting fasteners.
(4) Disconnect wire harness connector.

INSTALLATION

(1) Connect wire harness connector.
(2) Position module. Install and tighten mounting

fasteners.

(3) Install driver seat cushion.
(4) Connect battery negative cable.

SENTRY KEY REMOTE ENTRY
MODULE

DESCRIPTION

The Sentry Key Remote Entry Module (SKREEM)

(Fig. 2) performs the functions of the Sentry Key
Immobilizer Module (SKIM) and the Remote Keyless
Entry (RKE) module.

SENTRY KEY IMMOBILIZER

The

Sentry

Key

Immobilizer

System

(SKIS)

authenticates an electronically coded Transponder
Key placed into the ignition and sends a valid/invalid
key message to the Engine Control Module (ECM)
based upon the results. The “VALID/INVALID KEY”
message communication is performed using a rolling
code algorithm. A “VALID KEY” message must be
sent to the ECM within two seconds of ignition ON
to free the engine from immobilization. This Control-
ler Area Network (CAN) data bus message is sent to
the ECM after first going through the SKREEM. The
SKREEM is located behind the instrument cluster
and has a separately mounted antenna ring mounted
around the ignition cylinder (Fig. 3) which picks up
the transponder key signal.

Fig. 1 DOME LAMP/INTRUSION SENSOR

1 - NOTCH
2 - SENSOR (3)
3 - HOUSING
4 - SWITCH (2)

Fig. 2 SENTRY KEY REMOTE ENTRY MODULE

(SKREEM)

8Q - 2

VEHICLE THEFT SECURITY

REMOTE KEYLESS ENTRY (RKE)

The RKE transmitter uses radio frequency signals

to communicate with the Sentry Key Remote Entry
Module (SKREEM). The SKREEM is hardwired to
the Central Timer Module (CTM). When the operator
presses a button on the transmitter, it sends a spe-
cific request to the SKREEM. In turn, the SKREEM
sends the appropriate request to the CTM to unlock
the vehicle doors.

OPERATION

SENTRY KEY IMMOBILIZER

The Sentry Key Remote Entry Module (SKREEM)

receives an encrypted Radio Frequency (RF) signal
from the transponder key which is read by the
remotely mounted antenna ring at the ignition cylin-
der. The SKREEM then decrypts the signal and
broadcasts the requested remote commands to the
appropriate modules in the vehicle over the Control-
ler Area Network (CAN) data bus. A valid transpon-
der key ID must be incorporated into the RF signal
in order for the SKREEM to pass the message on to
the appropriate modules.

Automatic transponder key synchronization is done

by the SKREEM if a valid transponder key is
inserted into the ignition cylinder, and the ignition is
turned ON. This provides a maximum operation win-
dow for RKE functions.

Each Sentry Key Remote Entry System (SKREES)

consists of a SKREEM, an antenna ring mounted
around the ignition cylinder, and a transponder key.
Each system has a secret key code unique to that
system. The secret key is electronically coded in the
SKREEM and in all programmed transponder keys.
It is used for immobilization and RKE functions for
data security. In addition, each transponder key will
have a unique identification.

REMOTE KEYLESS ENTRY

After pressing the lock button on the RKE trans-

mitter, all of the door locks will lock, the illuminated
entry will turn off (providing all doors are closed),
and the VTSS (if equipped) will arm. After pressing
the unlock button, on the RKE transmitter, one time,
the driver door lock will unlock, the illuminated
entry will turn on the courtesy lamps, and the VTSS
(if equipped) will disarm. After pressing the unlock
button a second time, the remaining door locks will
unlock.

The SKREEM is capable of retaining up to 8 indi-

vidual access codes (8 transmitters). If the PRNDL is
in any position except park, the SKREEM will dis-
able the RKE. Use a diagnostic scan tool or the cus-
tomer programming method to program the RKE
system. However, the SKREEM will only allow RKE
programming when the ignition is in the ON posi-
tion, the PRNDL is in park position, and the VTSS
(if equipped) is disarmed.

REMOVAL

SENTRY KEY REMOTE ENTRY MODULE

(1) Open hood, disconnect and isolate the battery

negative cable.

(2) Wait two minutes for the system reserve capac-

itor to discharge before beginning any system or com-
ponent service.

(3) Remove top cover - cluster (Refer to 23 -

BODY/INSTRUMENT PANEL/TOP COVER - CLUS-
TER - REMOVAL).

(4) Disconnect the one electrical connector to the

SKREEM (Fig. 4) which is the transponder ring con-
nector.

Fig. 3 TRANSPONDER RING

VEHICLE THEFT SECURITY

8Q - 3

Content .. 79 80 81 82 ..