Antitheft and Alarm Systems: Description and Operation

VEHICLE THEFT SECURITY SYSTEM (VTSS)
The vehicle theft security system is controlled by the body control module and is standard equipment on all Prowler vehicles. It monitors the doors, decklid, hood and ignition circuit to determine if the alarm should be triggered and engine disabled. When the system is armed, the BCM removes the ground from the decklid release switch thereby preventing a thief from accessing the trunk area.

When the alarm is triggered, the engine becomes disabled. In addition the horn is pulsed, the headlamps and marker lights will flash for (3) three minutes. After the 3 minute alarm has expired the BCM will return to an armed state and ignore the input(s) that triggered the initial alarm, unless those inputs return to an inactive state. The VTSS LED will also flash at a new rate indicating that the vehicle has been tampered with. All other monitored inputs will re-trigger the (3) minute alarm if they become active.

If during the (3) minute alarming period the BCM receives a request from the RKE module to enter panic mode, the BCM will cancel the (3) minute alarm, return to VTSS armed state and then perform the RKE panic feature.

INTRODUCTION
Vehicles equipped with the Vehicle Theft Security System (VTSS) system, the doors, deck lid, hood and ignition circuit are monitored by the Body Control Module (BCM) when the system is armed. The VTSS will prevent the engine from starting until the BCM receives a disarm signal. If the VTSS is triggered, the horn will pulse, headlamps/marker lamps will flash, and the VTSS warning lamp will flash. If BCM determines the threat to be false and the VTSS is not triggered again, the system will shut down and rearm itself after three minutes. The VTSS monitoring portion of the system is split into two sections. The engine compartment section and the passenger compartment section. If a malfunction occurs in the engine compartment section, the passenger compartment section would still arm and function normally. If an electrical malfunction occurs in either section of the system a Diagnostic Trouble Code (DTC) would be stored the BCM memory to aid system repair. DTC(s) can be retrieved using scan tool (DRB) attached to the diagnostic connector above the accelerator pedal.

Enabling
The Body Control Module is shipped with the VTSS feature enabled state. Upon enabling the VTSS on the BCM, it will start transmitting the OK to start message to the Powertrain Control Module. At this time the visual alarm outputs the headlamps and marker lamps will function. However the audio alarm output the horn and engine disable portion of the VTSS will not function until there has been four consecutive engine run cycles. When this has occurred the total VTSS will function.

If during alarm being set the BCM receives a request from the RKE module to enter PANIC mode the BCM will cancel the alarm, return VTSS armed state and then perform the RKE PANIC feature.

Deck Lid
Access to the deck lid area of the vehicle will not be allowed without disarming the system. When the VTSS is properly disarmed the tamper alert feature will pulse the horn three times if an attempt tamper with the deck lid has taken place.

SYSTEM OPERATION
Arming Procedure
Method-A
With the ignition key removed from the ignition switch and any door open, actuate one of the following:
- Power door lock button to LOCK,
- Key fob LOCK button
- Door lock key cylinder to locked position
- Arm switch

Upon closure of the deck lid and the last door, an arming time-out period of sixteen seconds will start, then the VTSS will become armed.

Method-B
Actuating the key fob transmitter LOCK button, manually locking the doors with a key when both doors already closed, and the ignition switch in the locked position will begin the arming time-out period. If method-A, 16 second time-out sequence was in process when method-B was actuated, the 16 second time-out will restart from the time of the second actuation.

If the security lamp does not illuminate at all upon final door closure, it indicates that the system is not arming.

The current VTSS status armed or disarmed shall be maintained in memory to prevent battery disconnects from disarming the system.

Time-Out Period
The VTSS requires 16 consecutive seconds to timeout and arm the alarm. If a door is key unlocked, key fob unlocked. or the ignition is switched ON, the VTSS will cancel out. To reset the VTSS, perform Methods A or B.

Triggering the VTSS
After the VTSS is armed, following actions will trigger the alarm:
- Opening of either door.
- Opening the hood
- Opening the deck lid
- Turning the ignition switch to the ON or unlock position.