Antitheft and Alarm Systems: Description and Operation

VEHICLE THEFT SECURITY SYSTEM
The Vehicle Theft Security System (VTSS) is an available factory-installed option on this model. Vehicles with this option are also equipped with a Central Timer Module (CTM). The VTSS is designed to provide perimeter protection against unauthorized use or tampering by monitoring the vehicle doors and the ignition system. If unauthorized vehicle use or tampering is detected, the system responds by pulsing the horn, flashing the headlamps, and preventing the engine from operating.

The VTSS includes the following major components, which are described in further detail elsewhere:
- 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). The CTM is concealed under the instrument panel, where it is secured with three screws to the inboard side of the left center instrument panel support above the engine housing. The CTM provides the proper VTSS features based upon the monitored inputs. The CTM circuitry monitors hard wired switch inputs, as well as message inputs received from other vehicle electronic modules on the Chrysler Collision Detection (CCD) data bus network. (Refer to ELECTRONIC CONTROL MODULES/BODY CONTROL/CENTRAL TIMER MODULE - DESCRIPTION).
- Door Ajar Switch - A door ajar switch is located on the hinge pillar of each door in the vehicle. These switches provide an input to the VTSS indicating whether the door is opened or closed. (Refer to LAMPS/LIGHTING - INTERIOR DOOR AJAR SWITCH - DESCRIPTION).
- Door Cylinder Lock Switch - A door cylinder lock switch is located on the back of each front door lock cylinder. This switch provides an input to the VTSS indicating whether the system should remain armed or be disarmed. (Refer to POWER LOCKS/DOOR CYLINDER LOCK SWITCH - DESCRIPTION).
- Horn Relay - The horn relay is located in the relay and fuse block on the left outboard end of the instrument panel in the passenger compartment. The horn relay is normally activated by the horn switch to control the sounding of the vehicle horn or horns. However, it can also be activated by an output of the Central Timer Module (CTM) to provide an audible indication that unauthorized vehicle use or tampering has been detected. (Refer to HORN/HORN RELAY - DESCRIPTION).
- Headlamp Relay - The headlamp relay (also known as the security relay) is located in the relay and fuse block on the left outboard end of the instrument panel in the passenger compartment. The headlamp relay is activated by an output of the Central Timer Module (CTM) to flash the headlamp low beams to provide a highly visible indication that unauthorized vehicle use or tampering has been detected. (Refer to LAMPS/LIGHTING - EXTERIOR/HEADLAMP RELAY - DESCRIPTION).
- Security Indicator - A red Light Emitting Diode (LED) located in the ElectroMechanical Instrument Cluster (EMIC) is illuminated by an output of the Central Timer Module (CTM) to indicate the status of the VTSS. (Refer to INSTRUMENT CLUSTER/SECURITY INDICATOR - DESCRIPTION).

The engine no-run feature of the VTSS relies upon communication between the CTM and the Powertrain Control Module (PCM) over the Chrysler Collision Detection (CCD) data bus network.

Hard wired circuitry connects many of the VTSS components to each other through the electrical system of the vehicle. These hard wired circuits are integral to several wire harnesses, which are routed throughout the vehicle and retained by many different methods. These circuits may be connected to each other, to the vehicle electrical system and to the VTSS components through the use of a combination of soldered splices, splice block connectors, and many different types of wire harness terminal connectors and insulators.

A Central Timer Module (CTM) is used on this model to control and integrate many of the electronic functions and features included in the Vehicle Theft Security System (VTSS). In the VTSS, the CTM receives inputs indicating the status of the door ajar switches, the door cylinder lock switches, and the ignition switch. The programming in the CTM allows it to process the information from all of these inputs and send control outputs to energize or de-energize the horn relay, the headlamp relay, and the security indicator. The control of these inputs and outputs are what constitute all of the features of the VTSS. Following is information on the operation of each of the VTSS features. Refer to the owner's manual in the vehicle glove box for more information on the features, use and operation of the VTSS.

Enabling
The CTM must have the VTSS function electronically enabled in order for the VTSS to perform as designed. The logic in the CTM keeps its VTSS function dormant until it is enabled using a DRB III scan tool. The VTSS function of the CTM is enabled on vehicles equipped with the VTSS option at the factory, but a service replacement CTM must be VTSS-enabled by the dealer using a DRB III scan tool. Refer to the appropriate diagnostic information.

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 by the dealer 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 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, 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 buttons. Active arming of the VTSS occurs when the "Lock" button on the Remote Keyless Entry (RKE) transmitter is depressed 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.

Pre-arming of the VTSS is initiated when a side or rear door is open when the vehicle is locked using a power lock switch or a key in the door lock cylinder (passive), or when the RKE transmitter "Lock" button is depressed (active). Pre-arming will not occur if the key is in the ignition switch or the headlamps are turned ON with the driver side front door open. When the VTSS is pre-armed, the arming sequence is delayed until all of the side and rear doors have been closed.

Once the VTSS begins passive or active arming, the security indicator in the ElectroMechanical Instrument Cluster (EMIC) 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 indicator to stop flashing and the arming process to abort. Once the 15 second arming function is successfully completed, the indicator will flash at a slower rate, indicating that the VTSS is armed.

Disarming
Passive disarming of the 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 RKE transmitter. Once the alarm has been activated (horn pulsing, headlamps flashing, and the engine no-run feature), either disarming method will also deactivate the alarm.

Power-up Mode
When the armed 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 technician or vehicle operator will have to actively or passively disarm the alarm system 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. The VTSS will be armed until the technician or vehicle operator has actively or passively disarmed the alarm system. If the VTSS is in the disarmed mode prior to a battery disconnect or failure, it will remain disarmed after the battery is reconnected or replaced, or if jump-starting is attempted.

Tamper Alert
The VTSS tamper alert feature will sound the horn three times upon disarming, if the alarm was triggered and has since timed-out (about 15 minutes). This feature alerts the vehicle operator that the VTSS alarm was activated while the vehicle was unattended.

VEHICLE THEFT SECURITY SYSTEM (VTSS)
The VTSS will monitor the states of the ignition, door lock signal, and all other doors to alert against unauthorized entry into the vehicle. The VTSS will be enabled at the assembly plant. However to prevent the engine disable feature during assembly and the shipping process, the vehicle must be started 20 times before the VTSS will operate properly.

Arming The VTSS
To arm the system, the ignition must be OFF and all doors must be closed and locked using either front door key cylinder lock switch, power door lock switch or the RKE transmitter. Using a key in either rear door or pressing the mechanical lock will not initiate arming the VTSS. The delay lock feature will delay the arming process until all doors are closed.

Once the VTSS begins to arm, the CTM will activate the security lamp output at a 1 Hz rate. During this process the arming process will terminate if the ignition is turned ON, if a door is opened, if the doors are unlocked using the door lock switch or the RKE transmitter, or if the front doors are unlocked using the key. After fifteen seconds of the arming process, the security lamp will go OFF and the VTSS will be armed. Once the vehicle is armed the ignition may be turned to the accessory position (to listen to radio, etc.) without triggering the alarm. The VTSS can only be disarmed using the key or the RKE transmitter.

Triggering The VTSS
Once the VTSS is armed, the alarm Will trigger if any of the doors are opened or if the key is turned the Run/Start position. When triggered, the CTM will instruct the PCM to turn OFF the engine after two seconds and will pulse the horn and headlamps at a specified duty cycle and frequency. The audible (horn) warning will continue for three minutes then terminate. The visual (headlamps) warning will continue for fifteen additional minutes then terminate. The engine will continue to start and quit until the VTSS is disarmed.

Tamper Alert
If the VTSS was triggered during the last armed period, the next time it is disarmed the CTM will activate three horn chirps. To determine what caused the alarm to be tripped, using the DRB select "Theft Alarm" "Monitor Display" and observe: "Alarm Tripped by". This is a great tool to use when a customer complains that the alarm went OFF and cannot determine what triggered it.