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 headlamps, and providing an engine no-run feature.

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

Enabling
The Vehicle Theft Security System (VTSS) feature is enabled in the Central Timer Module (CTM) before the vehicle is shipped from the factory. However, the VTSS engine no-run feature is disabled when the vehicle 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 headlamps are turned off, and the doors are locked while they are open using the power lock switch. 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 key in the lock cylinder or 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 fifteen 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 fifteen second arming process will cause the security lamp to stop flashing and the arming process to abort. Once the fifteen 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 front 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 timed out (about fifteen minutes). This feature alerts the vehicle operator that the VTSS was activated while the vehicle was unattended.

SYSTEM OPERATION
Central Timer Module
A Central Timer Module (CTM) is used on this vehicle when it is equipped with the optional Vehicle Theft Security System (VTSS). In addition to serving as the security system module, the CTM combines the functions of a chime/buzzer module, an intermittent wipe module, an illuminated entry module, and a Remote Keyless Entry (RKE) module in a single unit.

The CTM is also able to control and integrate many of the additional electronic functions and features included on models with this option. 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 CTM supports and controls is the Vehicle Theft Security System (VTSS). In the VTSS, the CTM receives hard--wired inputs from the door ajar, front 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 (or security) 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 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 function; of the VTSS.

The CTM is mounted under the instrument panel, to the inboard side of the left center instrument panel support. Refer to Central Timer Module in Instrument Panel, Gauges and Warning Indicators/Instrument Panel/

The programmable features of the CTM can be enabled or disabled using the DRB scan tool as described in the proper Diagnostic Procedures. For diagnosis of the CTM or the CCD data bus, a DRB 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 integra to the door latches on each front door. The door ajar switches for the side and rear doors are mounted to the door opening pillars. Each of these 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 (front doors) or door ajar switch unit (side or rear doors) 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 normally-open momentary witches that close to ground only when the lock cylinder is rotated to the unlock position.

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

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 a connector that is taped back to the headlamp switch takeout of the instrument panel wire harness in the passenger compartment. To service the headlamp relay remove the headlamp switch mounting screws and pull the switch and wire harness out from the instrument panel far enough to access the relay and connector.

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

Horn Relay
The horn relay is a component of the Remote Keyless Entry (RKE) system only on vehicles equipped with the optional Vehicle Theft Security System (VTSS). 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 Central Timer Module (CTM) grounds the relay coil. See Horn Relay in the Diagnosis and Testing for more information.

The horn relay is located in the junction block, which is located on the driver side end of the instrument panel in the passenger compartment. If a problem is encountered with a continuously sounding horn, it can usually be quickly resolved by removing the horn relay from the junction block 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 an amber lamp located within the instrument cluster on the instrument panel. The security lamp receives fused battery feed at all times and is grounded by the high line Central Timer Module (CTM) to give a visible indication of the Vehicle Theft Security System (VTSS) arming status.

The security lamp incandescent bulb and bulb holder can be serviced. Refer to Instrument Panel, Gauges and Warning Indicators/Cluster Bulbs Service Procedures.