Battery positive voltage (B+) is applied at all times through the RH rear fuse block PWR DR LK fuse via CKT 1540 (ORN) through the body control module (MALL) and through CKT 1732 (ORN) to the garage door opener terminal 1. This power circuit also supplies power to the vehicle courtesy lamps. The garage door opener is grounded on terminal 3 at all times via CKT 1050 (BLK) to ground G302.

A detailed explanation of the body control module (MALL) diagnostic mode is provided in Body Control System.