Backup Lamp: Description and Operation
BACKUP LAMPSOn a vehicle equipped with an automatic transmission, the backup lamps request signal is sent from the powertrain control module (PCM) to the body control module (BCM) via class 2. This signal is based on the state of the park neutral position (PNP) switch. When the driver places the gear selector lever in the REVERSE position, a class 2 signal is sent from the PCM to the BCM requesting backup lamp illumination.
The BCM directly supplies voltage for backup lamp operation. The backup lamps are grounded at G402.