Antitheft and Alarm Systems: Description and Operation

INTRODUCTION
The Vehicle Theft Security System (VTSS) is an available factory-installed option on this model.

VEHICLE THEFT SECURITY SYSTEM
The Vehicle Theft Security System (VTSS) is designed to provide perimeter protection against unauthorized use or tampering by monitoring the vehicle doors and the ignition system. If unauthorized use or tampering is detected, the system responds by sounding the horn, flashing the head- lamps, and providing an engine no-run feature.

Following are general descriptions of the features and major components of the VTSS. Refer to the vehicle glove box for more information on the features, use and operation of the vehicle theft security system.

Enabling
If the vehicle is so equipped, the Vehicle Theft Security System (VTSS) feature is enabled in the high-line Central Timer Module (CTM) before the vehicle is shipped from the factory. However, if a vehicle with VTSS requires CTM replacement, the VTSS feature must be enabled in the new CTM using a DRB III scan tool. Refer to the Vehicle Theft Security System menu item on the DRB III scan tool for the procedures.

The VTSS engine no-run feature is disabled when it is shipped from the factory. This is done by programming within the Powertrain Control Module (PCM). The logic in the PCM prevents the VTSS engine no-run feature from arming until the engine start counter within the PCM sees twenty engine starts. The VTSS no-run feature must be enabled when the vehicle is received from the assembly plant.

Once the VTSS engine no-run feature has been enabled, it cannot be disabled unless the PCM is replaced with a new unit. The same VTSS engine no-run feature enable logic will apply anytime the PCM is replaced with a new unit.

Arming
Passive arming of the Vehicle Theft Security System (VTSS) occurs when the vehicle is exited with the key removed from the ignition switch, the head- lamps are turned off, and the doors are locked while they are open using the power lock switch or locked after they are closed by turning either front door lock cylinder to the lock position using the key. The power lock switch will not function if the key is in the ignition switch or the headlamps are turned on with the driver side front door open. The VTSS will not arm if the doors are locked using the mechanical lock button.

Active arming of the VTSS occurs when the Remote Keyless Entry (RKE) transmitter is used to lock the vehicle. For active arming to occur, the doors must be closed and the ignition switch must be in the OFF position when the RKE transmitter Lock button is depressed. However, once the VTSS arming process has been completed, the ignition switch can be turned to the Accessory position without triggering the alarm.

Once the VTSS begins passive or active arming, the security lamp in the instrument cluster will flash rapidly for about 15 seconds. This indicates that the VTSS arming is in progress. Turning a key in the ignition switch, opening a door, or unlocking a door by any means during the 15 second arming process will cause the security lamp to stop flashing and the arming process to abort. Once the 15 second arming function is successfully completed, the security lamp will stop flashing to indicate that the VTSS is armed.

Disarming
Passive disarming of the Vehicle Theft Security System (VTSS) occurs when the vehicle is unlocked using the key to unlock either door. Active disarming of the VTSS occurs when the vehicle is unlocked by depressing the Unlock button of the Remote Keyless Entry (RKE) transmitter.

Once the alarm has been activated (horn sounding, headlamps flashing, and the engine no-run feature), either disarming method will also deactivate the alarm.

Power-Up Mode
When the armed Vehicle Theft Security System (VTSS) senses that the battery has been disconnected and reconnected, it enters its power-up mode. In the power-up mode the alarm system remains armed following a battery failure or disconnect. If the VTSS was armed prior to a battery disconnect or failure, the system will have to be actively or passively disarmed after the battery is reconnected.

The power-up mode will also apply if the battery goes dead while the system is armed, and battery jump-starting is attempted. The engine no-run feature will prevent the engine from starting until the alarm system has been actively or passively disarmed.

Tamper Alert
The Vehicle Theft Security System (VTSS) tamper alert will sound the horn three times upon disarming, if the alarm was triggered and has since out (about fifteen minutes). This feature alerts the vehicle operator that the VTSS was activated while the vehicle was unattended.

CENTRAL TIMER MODULE
Two versions of the Central Timer Module (CTM) are available on this vehicle, a base version and a high-line version. The base version of the CTM is used on base models of the vehicle. The base version of the CTM combines the functions of a chime/buzzer module and an intermittent wipe module into a single unit. The base CTM also uses inputs from the door ajar switches, the headlamp switch and the key-in ignition switch to control the output to the dome lamp circuits, which allows the base CTM to provide load shedding to help protect the battery from becoming discharged.

The high-line version of the CTM is used on high-line vehicles. The high-line CTM provides all of the functions of the base version CTM, but also is used to control and integrate many of the additional electronic functions and features included on the high- line models. The high-line version of the CTM contains a central processing unit and interfaces with other modules in the vehicle on the Chrysler Collision Detection (CCD) data bus network.

The CCD data bus network allows the sharing of sensor information. This helps to reduce wire harness complexity, reduce internal controller hardware, and reduce component sensor current loads. At the same time, this system provides increased reliability, enhanced diagnostics, and allows the addition of many new feature capabilities.

One of the features that the high-line CTM supports and controls is the Vehicle Theft Security System (VTSS). In the VTSS, the CTM receives hard- wired inputs from the door jamb, door lock cylinder, and ignition switches. The programming in the CTM allows it to process the information from these inputs and send control outputs to energize or de-energize the headlamp relay, horn relay, and the security lamp. The CTM also sends CCD data bus messages to the Powertrain Control Module (PCM) to control the engine no-run feature of the VTSS

The high-line CTM also contains the receiver and control logic for the power lock and Remote Keyless Entry (RKE) systems, which are integrated into the arming, disarming, and triggering functions of the VTSS.

Both versions of the CTM are mounted under the passenger side end of the instrument panel, outboard of the instrument panel glove box opening. Refer to Central Timer Module in the Removal and Installation of Instrument Panel Systems for the service procedures.

For diagnosis of the high-line version of the CTM or of the CCD data bus, a DRB III scan tool and the proper Diagnostic Procedures are recommended. The CTM cannot be repaired and, if faulty or damaged, it must be replaced.

DOOR AJAR SWITCH
The door ajar switches are integral to the door latches on each door. The switches close a path to ground for the Central Timer Module (CTM) when a door is opened, and open the ground path when a door is closed.

The door ajar switches cannot be repaired and, if faulty or damaged, the door latch unit must be replaced.

DOOR LOCK CYLINDER SWITCH
The door lock cylinder switches are mounted to the back of the key lock cylinder inside each front door. They are resistor multiplexed momentary switches that are hard wired between a body ground and the Central Timer Module (CTM) through the front door wire harnesses. These switches are driven by the key lock cylinders and contain three internal resistors. One resistor is used for the neutral switch position, one for the lock position and one for the unlock position.

The door lock cylinder switches cannot be adjusted or repaired and, if faulty or damaged, they must be replaced.

The door lock cylinder 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 lock cylinder switch closes a path to ground through one of three internal resistors for the CTM when the front door key lock cylinder is in the lock, unlock or neutral positions. The CTM reads the switch status through an internal pull-up, then uses this input and its internal programming to control the proper Vehicle Theft Security System (VTSS) and power lock system outputs.

HEADLAMP RELAY
The headlamp (or security) relay is a International Standards Organization (ISO) micro-relay. The terminal designations and functions are the same as a conventional ISO relay. However, the micro-relay terminal orientation (or footprint) is different, current capacity is lower, and the relay case dimensions are smaller than those of the conventional ISO relay.

The headlamp relay is a electromechanical device that switches battery current to the headlamps when the high-line Central Timer Module (CTM) grounds the relay coil. See Headlamp Relay in the Diagnosis and Testing for more information.

The headlamp relay is located in the Power Distribution Center (PDC), behind the battery on the left side of the engine compartment.

The headlamp relay cannot be repaired and, if faulty or damaged, it must be replaced.

HORN RELAY
The horn relay is a International Standards Organization (ISO) micro-relay. The terminal designations and functions are the same as a conventional ISO relay. However, the micro-relay terminal orientation (or footprint) is different, current capacity is lower, and the relay case dimensions are smaller than those of the conventional ISO relay.

The horn relay is a electromechanical device that switches battery current to the horn when the horn switch or the high-line Central Timer Module (CTM) grounds the relay coil. Refer to Relays in the Diagnosis and Testing for more information.

The horn relay is located in the Junction Block (JB), on the left end of the instrument panel in the passenger compartment. See the fuse and relay layout label on the inside of the fuse access panel for relay identification and location.

If a problem is encountered with a continuously sounding horn, it can usually be quickly resolved by removing the horn relay from the JB until further diagnosis is completed.

The horn relay cannot be repaired and, if faulty or damaged, it must be replaced.

SECURITY LAMP
The security lamp is located within the instrument cluster on the instrument panel. The security lamp is illuminated by a red Light-Emitting Diode (LED) that is integral to the instrument cluster circuit board. The security lamp receives fused battery feed at all times and is grounded by the high-line Central Timer Module (CTM) to give a visual indication of the Vehicle Theft Security System (VTSS) arming status.

The security lamp cannot be repaired and, if faulty or damaged, the instrument cluster unit must be replaced. Refer to Instrument Cluster in the Removal and Installation of Instrument Panel Systems for the service procedures.