Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Backup Lights Circuit Description

The BACKUP LAMPS Relay in the RH I/P 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