Courtesy Lamp: Description and Operation

READING COURTESY LAMPS
The INT LAMP relay provides battery positive voltage to each of the reading courtesy lamps. When the switch is closed on the reading lamp, this provides a ground circuit to G402, and the reading lamp illuminates.

DOOR ACTIVATED COURTESY LAMPS
If the sunload sensor detects a low light condition, the IPM applies a class 2 message to the RIM indicating a low light level. When the LH front door is opened, the door lock actuator contacts close and the driver door module (DDM) receives a door-open signal. The DDM then applies a class 2 message to the RIM. When the RIM receives a door open input signal, the RIM will activate the INT LAMP relay, which provides battery positive voltage to all interior courtesy lamps. The RIM then applies a ground to the courtesy lamps ground control circuit illuminating the all courtesy lamps. After all the doors are closed, the courtesy lamps remain illuminated for approximately 25 seconds. The courtesy lamps will also turn on and remain illuminated for approximately 15 seconds after the ignition key is removed, prior to any door being opened.

When a passenger door is opened and the RIM has received a low light message, the door lock actuator contacts close and the corresponding door module receives a door-open signal. The door module then communicates through the power door serial data circuit to the DDM. The DDM then applies a class 2 message to the RIM. When the RIM receives a door lock command, the RIM will activate the INT LAMP relay, which provides battery positive voltage to all interior courtesy lamps. The RIM then applies a ground to the courtesy lamps ground control circuit illuminating the all courtesy lamp.