designed to protect against whole vehicle theft. The
system monitors vehicle doors, deck lid key cylinder,
and ignition action for unauthorized operation. The
alarm activates:

• Sounding of the horn

• Flashing of the park and tail lamps

• Flashing of the headlamps

• An engine kill feature (without SKIS)

SENTRY KEY IMMOBILIZER SYSTEM

The Sentry Key Immobilizer System (SKIS) is

designed to provide passive protection against unau-
thorized vehicle use by preventing the engine from
operating. The components of this system are the
Sentry Key Immobilizer Module (SKIM) (Fig. 1),
Body Control Module (BCM), Sentry Key transpon-
der, VTSS indicator LED, and the Powertrain Con-
trol Module (PCM).

The SKIM is installed on the steering column near

the ignition lock cylinder. The transponder is located
under the molded rubber cap on the head of the igni-
tion key. The VTSS indicator LED is located in the
instrument panel top cover.

TRIGGERING THE VTSS

Any of the following actions will trigger the sys-

tem:

(1) Opening any door.
(2) Removing the deck lid lock cylinder.
(3) Turning the ignition to the ON position.

Using the power door switch or the keyless trans-

mitter will arm the system.

CAUTION: The VTSS indicator LED will trigger and
engine will continue to run if the vehicle is
equipped with SKIS and the proper key is used to
start the vehicle. This condition will occur if the
VTSS has been triggered.

Fig. 1 SENTRY KEY IMMOBILIZER MODULE

LOCATION

1 - STEERING WHEEL
2 - IGNITION KEY CYLINDER
3 - STEERING COLUMN
4 - SENTRY KEY IMMOBILIZER MODULE

VEHICLE THEFT SECURITY

8Q - 1

NOTE: The ignition switch can be turned to the
accessory position without triggering alarm system.

OPERATION

VEHICLE THEFT SECURITY SYSTEM

Upon failure of proper VTSS/SKIM communication

to the PCM, the PCM will shut off fuel after two sec-
onds of run time. The engine will not re-crank on the
key cycle that the failure occurred, a full key down
sequence must be performed for the engine to crank
again. After six consecutive fuel shut-offs, the engine
will no longer crank on subsequent key cycles. The
failure must be corrected and a valid communication
process between the BCM (VTSS), or SKIM, and the
PCM must occur for the engine to crank and start
again.

The electronics for the VTSS are part of the Body

Control Module (BCM). The system is armed when
the vehicle is locked using the:

• Power door lock switches

• Remote Keyless Entry transmitter.

• Door Cylinder Lock Switches.
For vehicles equipped with SKIS, the doors do not

have to be locked to enable the fuel shut off feature.

After the vehicle is locked and the last door is

closed, the set LED indicator in the top cover will
flash quickly for 16 seconds, indicating that arming
is in progress. If no monitored systems are activated
during this period, the system will arm. After 16 sec-
onds the indicator LED will continue to flash at a
slower rate.

This indicates that the system is armed. If the

deck lid key cylinder switch is not sensed by the sys-
tem, the indicator LED will remain lit during the
arming process, although the system will still arm. If
the indicator LED does not illuminate at all upon
door closing it indicates that the system is not arm-
ing.

Passive disarming occurs upon normal vehicle

entry by unlocking either door with the ignition key/
remote transmitter. This disarming will also halt the
alarm once it has been activated.

A tamper alert exists to notify the driver that the

VTSS had been activated. This alert consists of 3
horn pulses when the vehicle is disarmed.

NOTE: The VTSS will not arm by pushing down the
door lock mechanism. This will manually override
the system.

For Door Cylinder Lock Switch Removal and

Installation, refer to Electrical, Power Locks, Door
Cylinder Lock Switch.

SENTRY KEY IMMOBILIZER SYSTEM

The SKIS includes two valid Sentry Key transpon-

ders from the factory. These two Sentry Keys can be
used to program additional non-coded blank Sentry
Keys. These blank keys can be cut to match a valid
ignition key, but the engine will not start unless the
key transponder is also programmed to the vehicle.
The SKIS will recognize no more than eight valid
Sentry Key transponders at any one time.

The SKIS performs a self-test each time the igni-

tion switch is turned to the ON position, and will
store Diagnostic Trouble Codes (DTC’s) if a system
malfunction is detected. The SKIS can be diagnosed,
and any stored DTC can be retrieved using a DRB
III

t scan tool as described in the proper Body Diag-

nostic Procedures Manual.

DIAGNOSIS AND TESTING

DIAGNOSIS AND TESTING - SENTRY KEY
IMMOBILIZER SYSTEM

WARNING: ON VEHICLES EQUIPPED WITH AIR-
BAGS,

REFER

ELECTRICAL,

RESTRAINTS,

WARNINGS, BEFORE ATTEMPTING COMPONENT
DIAGNOSIS OR SERVICE. FAILURE TO TAKE THE
PROPER PRECAUTIONS COULD RESULT IN ACCI-
DENTAL AIRBAG DEPLOYMENT AND POSSIBLE
PERSONAL INJURY.

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 involves the use of
a DRB III

scan tool. Refer to the proper Body Diag-

nostic Procedures Manual.

The Sentry Key Immobilizer System (SKIS) and

the Programmable Communication Interface (PCI)
bus network should be diagnosed using a DRB III

scan tool. The DRB III

t will allow confirmation that

the PCI bus is functional, that the Sentry Key Immo-
bilizer Module (SKIM) is placing the proper messages
on the PCI bus, and that the Powertrain Control
Module (PCM) is receiving the PCI bus messages.
Refer to the proper Body Diagnostic Procedures Man-
ual, and Wiring Diagrams for complete circuit
descriptions and diagrams.

(1) Check the fuses in the junction block. If OK, go

to Step 2. If not OK, repair the shorted circuit or
component as required and replace the faulty fuse.

8Q - 2

VEHICLE THEFT SECURITY

VEHICLE THEFT SECURITY (Continued)

(2) Disconnect and isolate the battery negative

remote cable from the remote terminal. Unplug the
wire harness connector at the SKIM. Check for con-
tinuity between the ground circuit cavity of the
SKIM wire harness connector and a good ground.
There should be continuity. If OK, go to Step 3. If not
OK, repair the open circuit to ground as required.

(3) Connect the battery negative remote cable.

Check for battery voltage at the fused B(+) circuit
cavity of the SKIM wire harness connector. If OK, go
to Step 4. If not OK, repair the open circuit to the
fuse in the junction block as required.

(4) Turn the ignition switch to the ON position.

Check for battery voltage at the fused ignition switch
output (run/start) circuit cavity of the SKIM wire
harness connector. If OK, use a DRB III

t scan tool

and the proper Body Diagnostic Procedures Manual
to complete the diagnosis of the SKIS. If not OK,
repair the open circuit to the fuse in the junction
block as required.

DIAGNOSIS AND TESTING - VEHICLE THEFT
SECURITY SYSTEM

Using a DRB III

t scan tool and the proper Body

Diagnostic Procedures manual, each switch input can
be checked using this method.

For complaints about the Theft Alarm going off on

it’s own, use the DRB III

t scan tool and select “Theft

Alarm”, “VTSS” then “Monitor Display” and read the
“Alarm Tripped By” status.

DECKLID SECURITY SWITCH

REMOVAL

(1) Open hood, disconnect and isolate the negative

battery cable remote terminal from the remote bat-
tery post.

(2) Refer to Body, Deck Lid, Deck Lid Latch

Removal.

(3) Disconnect connector and remove deck lid lock

cylinder from bracket (Fig. 2), (Fig. 3), and (Fig. 4).

INSTALLATION

(1) Connect connector and install the deck lid lock

cylinder onto bracket (Fig. 2), (Fig. 3), and (Fig. 4).

(2) Refer to Body, Deck Lid, Deck Lid Latch,

Installation.

Fig. 2 DECK LID LATCH - CONCORDE/LHS

1 - TRUNK LID
2 - TRUNK LID CYLINDER BRACKET
3 - TRUNK LID LATCH
4 - LOCK SET
5 - TRUCK LID LOCK CYLINDER
6 - TRUNK LID OVER SLAM BUMPERS

Fig. 3 DECK LID LATCH - INTREPID

1 - LOCK CYLINDER BRACKET
2 - LOCK SET
3 - TRUNK LID
4 - TRUNK LID LATCH
5 - TRUNK LOCK CYLINDER

VEHICLE THEFT SECURITY

8Q - 3

VEHICLE THEFT SECURITY (Continued)

(3) Connect the negative battery cable remote ter-

minal onto the remote battery post.

SKIS INDICATOR LAMP

DESCRIPTION

The Sentry Key Immobilizer System (SKIS) uses

the Vehicle Theft Security System (VTSS) indicator
LED to give an indication when the SKIS is faulty or
when the vehicle has been immobilized due to the
use of an invalid ignition key. The LED is controlled
by the BCM based upon messages received from the
Sentry Key Immobilizer Module (SKIM). The VTSS/
SKIS indicator LED is hard wired directly to the
BCM.

OPERATION

The SKIM sends messages to the BCM to turn the

LED on for about three seconds when the ignition
switch is turned to the ON position as a bulb test.
After completion of the bulb test, the SKIM sends
bus messages to the BCM to keep the LED off for a
duration of about one second. Then the SKIM sends
messages to the BCM to turn the LED on or off
based upon the results of the SKIS self-tests. If the
VTSS indicator LED comes on and stays on after the
bulb test, it indicates that the SKIM has detected a
system malfunction and/or that the SKIS has become
inoperative. If the SKIM detects an invalid key when
the ignition switch is turned to the ON position, it

sends messages to the BCM to flash the VTSS indi-
cator LED.

The SKIM can also send messages to the BCM to

flash the LED and to generate a single audible chime
tone. These functions serve as an indication to the
customer that the SKIS has been placed in its “Cus-
tomer Learn” programming mode. See Sentry Key
Immobilizer System Transponder Programming in
this section for more information on the “Customer
Learn” programming mode.

The VTSS indicator LED is housed in the Auto-

matic Temperature Control (ATC) Sun Sensor located
in the instrument panel top cover. Refer to Group 8E
- Instrument Panel and Systems for service of ATC
Sun Sensor. If the VTSS indicator LED comes on and
stays on after the bulb test function, diagnosis of the
SKIS should be performed with a DRB III

t scan tool

and the proper Body Diagnostic Procedures Manual.

TRANSPONDER KEY

DESCRIPTION

The Sentry Key Immobilizer System (SKIS) uses a

transponder that is integral to each of two ignition
keys (Fig. 5) that are supplied with the vehicle when
it is shipped from the factory. The transponder chip
is insulated within a nylon mount inserted in the
head of the key, and invisible beneath a molded rub-
ber cap.

Fig. 4 DECK LID LATCH - 300M

1 - LOCK CYLINDER BRACKET AND LOCK CYLINDER
2 - LOCK SET
3 - TRUNK LID LATCH
4 - TRUNK LID

Fig. 5 TRANSPONDER KEY

1 - MOLDED CAP
2 - TRANSPONDER
3 - MOLDED CAP REMOVED
4 - SENTRY KEY

8Q - 4

VEHICLE THEFT SECURITY

DECKLID SECURITY SWITCH (Continued)

Content .. 112 113 114 115 ..