Test A: The Courtesy Lamps Are Inoperative

PINPOINT TEST A: THE COURTESY LAMPS ARE INOPERATIVE

Normal Operation
Fuse 18 (15A) in the central junction box (CJB) provides power through circuit 54 (LG/YE) to the lighting control module (LCM). The driver door module (DDM) monitors the LH front door ajar switch on circuit 867 (DB), and the remaining door ajar switches on circuit 627 (BK/OG). The door ajar switches provide a path for ground supplied through the ajar switches by circuit 57 (BK), indicating an open door. The DDM then sends a message over the standard corporate protocol (SCP) to command the LCM to supply power to the courtesy lamps on circuit 53 (BK/LB). The courtesy lamps are grounded through circuit 57 (BK).

This pinpoint test is intended to diagnose the following:
- Fuse
- Wiring, terminals or connectors
- LCM

A1-A3:

A4-A5: