Courtesy Lamp Circuit

WARNING: This page is about a different variant/trim than selected.

The courtesy lamp circuit includes the dome/reading lamps located on the headliner near the center of the windshield opening upper header and the cargo (or trunk) lamp located on the rear edge of the left quarter inner trim near the left trunk trim panel at the rear of the vehicle. The lamps in the courtesy lamp circuit are provided with battery voltage and ground by the Body Control Module (BCM) using internal low side drivers through two ground circuits based upon hard wired inputs from the ignition switch, the door ajar switches and the liftgate ajar switch. The BCM also uses electronic message inputs received from other electronic modules in the vehicle over the Controller Area Network (CAN) data bus to control these outputs.

When a door or liftgate ajar switch input to the BCM transitions to closed, the BCM will illuminate the courtesy lamps and keep them active for up to about 3 minutes. After all of the ajar switch inputs to the BCM transition to open, the BCM will keep the courtesy lamps illuminated for about 10 seconds. The BCM also provides courtesy lamp operation based upon certain inputs received from the Remote Keyless Entry (RKE) transmitter to provide an Illuminated Entry feature and in response to certain electronic message inputs received from the Occupant Restraint Controller (ORC) or the Electric Vehicle Control Unit (EVCU) over the CAN data bus.

For those lamps in the courtesy lamp circuit with independent switching such as the dome/reading lamps, the BCM provides a second feed to the switches using another internal low side driver through a separate load shed circuit. The BCM provides a battery saver (load shedding) feature for these lamps, which will automatically turn the lamps OFF if they are left ON for more than about fifteen minutes with the ignition switch in the OFF position.