Accessory Relay: Description and Operation

Locks, Latches and Entry Systems







Special Tools







Material

Principles of Operation

NOTE: The smart junction box (SJB) is also known as the generic electronic module (GEM).

The SJB receives inputs and delivers outputs to many of the electronically controlled features of the vehicle. The SJB constantly monitors the system under its control and reports a concern in the form of a diagnostic trouble code (DTC).

Power Door Locks
Regardless of the key position, the SJB is powered at all times. tn/hen the SJB receives a signal from the remote keyless entry (RKE) transmitter or door lock control switch the SJB supplies a ground signal to the appropriate lock or unlock relay. The ground signal closes the relay which supplies voltage to the door lock actuators. The door lock actuators then actuate to a lock or unlock position determined by the relay on the lock or unlock circuit.

Auto-locking
The auto-locking feature locks all the doors when all the doors (including the liftgate for wagon only) are closed, the key is in the RUN position, the transmission is in either a forward or reverse gear, the brake pedal has been pressed and released, and the vehicle speed is 5 km/h (3 mph) or higher. If any door becomes ajar, this feature relocks all the doors when the ajar door is returned to a closed position and all previous conditions are met.