Backup Lamps

The backup (or reverse) lamps have a path to ground at all times through a takeout and eyelet terminal of the body wire harness that is secured to the body sheet metal within the passenger compartment. On vehicles with a manual transmission, the backup lamp switch provides a hardwired input to the to the PCM through a backup lamp switch signal circuit, and the PCM sends the appropriate electronic reverse gear status messages to the BCM over the CAN data bus. The BCM then controls a battery feed to the backup lamps on the backup lamp feed circuit as required whenever the ignition switch status is ON.

On vehicles with an automatic transmission, the PCM continually monitors electronic an hardwired multiplex input from the Transmission Range Sensor (TRS), then sends the appropriate electronic gear selector status messages received from the Electronic Shift Module (ESM) over the CAN data bus, then relays the appropriate electronic reverse gear status messages to the BCM over the CAN data bus.