Body Control Systems: Description and Operation

Module Controlled Functions

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

The vehicle is equipped with an SJB and a Driver Seat Module (DSM).

Smart Junction Box (SJB)

NOTE: The time out for the battery saver relay and the accessory delay relay (both are controlled by the SJB) is 1 minute if the vehicle has less than 80 km (50 miles). Once the vehicle passes the approximate mileage threshold of 80 km (50 miles), the time out for both relays will be 10 minutes, as described in the Owner's Literature. For the battery saver relay, refer to Courtesy Lamp. For the accessory delay relay, refer to Windows. Testing and Inspection

The SJB is a combination of a multifunction electronic module and a Central Junction Box (CJB). The following systems are controlled by the SJB:

- Accessory delay relay
- Battery saver relay
- Exterior lighting
- Heated rear window
- Horn
- Interior lighting
- Perimeter anti-theft
- Post crash alert
- Power door locks (including smart locks, autolocking and liftgate/luggage compartment lid release)
- Remote Keyless Entry (RKE)/keyless entry keypad
- Tire Pressure Monitoring System (TPMS)

Post Crash Alert

A new function controlled by the SJB is the post crash alert. If the Restraints Control Module (RCM) determines an impact of severity enough to deploy air bags has occurred (the air bags may or may not be deployed by the RCM), the RCM will send a message to the Instrument Cluster (IC) over the High Speed Controller Area Network (HS-CAN), which will send the message to the SJB over the Medium Speed Controller Area Network (MS-CAN) and the SJB will activate the post crash alert function by cycling the horn on 3 times, then off for 4 seconds, then on 3 times, etc, in this cycle until the battery dies or the function is turned off. The hazard lights will also flash with the horn sounding, but will keep flashing during the horn off cycle.

The post crash alert function can be turned off by:

- pressing the hazard switch (may need to be pressed more than once).
- pressing the Integrated Keyhead Transmitter (IKT) UNLOCK button.
- pressing the IKT PANIC button.

Note this feature acts similar to the perimeter alarm, but the horn cycle is different. Turning the ignition key to the ON position will not deactivate this function, but will deactivate an activated perimeter alarm. The post crash alert function can not be configured off.

Driver Seat Module (DSM)

The DSM controls the user selected comfort functions. These functions are the memory seat, memory mirrors and memory pedals. Up to 2 personal settings can be programmed into the DSM memory and when selected, the DSM returns the user adjustable features to the programmed positions. For programming the memory feature, refer to Locks.