Principles of Operation

Anti-Theft

Principles of Operation

NOTE: The Smart Junction Box (SJB) is also known as the Generic Electronic Module (GEM).

The SJB monitors the door ajar switches, the hood switch and the luggage compartment lid ajar switch. When the SJB receives a signal from one or more of the monitored switch(es) indicating unauthorized entry into the vehicle (if the unauthorized entry is through a passenger door, hood or luggage compartment lid), the SJB intermittently (in regular intervals) grounds the horn relay and also intermittently (in regular intervals) sends voltage to the turn signal lamps. The horn relay closes, supplying voltage to the horn. The SJB cycles the ground to the horn relay and voltage to the turn signal lamps, on and off, while the perimeter alarm system is activated. If the SJB detects an unauthorized entry through the driver door, the Instrument Cluster (IC) issues a chime for 12 seconds and displays TO STOP ALARM START VEHICLE in the message center. If a valid, programmed PATS key does not turn the ignition to the on position within the 12 seconds, the IC issues a message to the SJB over the Medium Speed Controller Area Network (MS-CAN) to activate the perimeter alarm.

An activated alarm can either be deactivated or disarmed.

To Disarm the Alarm

The perimeter anti-theft feature (or an activated alarm) can be disarmed when either an unlock request is made through the RKE transmitter, or the ignition switch is turned to the ON position using a valid, programmed key.

To Deactivate the Alarm

Pressing the PANIC button on the Remote Keyless Entry (RKE) transmitter deactivates the perimeter alarm, but does not disarm the alarm.

The SJB monitors the key-in-ignition switch and does not allow the perimeter anti-theft feature to arm until after the key is removed from the ignition lock cylinder, all doors, hood and the luggage compartment lid are closed and 20 seconds have elapsed after locking the vehicle. Each input has its own 20-second pre-arm phase, depending on when it was closed after the arm command was given. After all of these criteria have been met, the anti-theft feature arms.

To Arm the Alarm

The perimeter anti-theft feature can be armed by either pressing the LOCK button on the RKE transmitter or pressing the door lock control switch to the lock position with the accompanying door open, then closing the door.