Backup Lamp: Description and Operation

The BACKUP LAMPS Relay in the RH I/IP Accessory Wiring Junction Block receives B+ at all the times for the coil side from the DIC/RKE fuse. B+ for the switched side of the relay is supplied from the B/U LAMP fuse.

When the vehicle is placed in REVERSE a class 2 signal is sent to the BCM. The BCM then applies a ground through the backup lamp relay coil feed control circuit to the backup lamps relay. This energizes the relay and allows B+ to be applied to the backup lamps turning them on. The backup lamps receive a constant ground signal.