Principles of Operation: Notes

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

The SJB monitors the door ajar switches (they are open with the door closed and closed with the door open), the hood switch (closed with the hood closed and open with the hood open) and the Liftgate/Trunk Module (LTM) monitors the liftgate ajar information and sends it to the SJB . If the perimeter alarm has been armed, when the SJB receives a signal from one or more of the monitored switches indicating unauthorized entry into the vehicle, 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 system is activated.

An activated alarm can either be deactivated or disarmed. Pressing the PANIC button on the Remote Keyless Entry (RKE) transmitter (part of the Integrated Keyhead Transmitter (IKT) key) will deactivate the perimeter alarm, but will 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 liftgate 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 (when the doors are electronically locked). After all of these criteria have been met, the perimeter anti-theft alarm feature will arm.

The perimeter anti-theft feature can be armed by either:

pressing the LOCK button on the IKT key).
pressing the door lock control switch to the LOCK position with the door open, then closing the door.
pressing the 7/8 and 9/0 buttons simultaneously to lock the vehicle using the keyless entry keypad (if equipped).

The perimeter anti-theft feature (or an activated alarm) can be disarmed when either:

the UNLOCK button on the IKT key) is pressed.
the driver door is manually unlocked with a key.
the ignition switch is turned to the ON position using a key.
the vehicle is unlocked using the keyless entry keypad (if equipped).

Pressing the PANIC button on the IKT key) will also deactivate the perimeter alarm, but will not disarm the alarm.