Principles of Operation

Reversing Lamps

Principles of Operation

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

For vehicles equipped with an automatic transaxle, the Transmission Control Module (TCM) sends gear status information to the instrument cluster over the communication network. The SJB receives transmission gear status from the instrument cluster over the communication network. When the ignition switch is in the RUN position and a message is sent over the communication network stating the transaxle is in REVERSE (R), the SJB energizes an internal relay which supplies voltage to the reversing lamps.

For vehicles equipped with a manual transaxle, the SJB supplies voltage to the reversing lamp switch when the ignition switch is in the RUN position. When the transaxle is placed in REVERSE (R), the switch routes the voltage to the reversing lamps.