Trunk Lamp: Description and Operation

REAR COMPARTMENT LAMP
When the rear compartment is opened, the rear compartment lamp illuminates.

When the rear compartment is opened, the rear compartment courtesy lamp switch sends a ground signal to the BCM, waking the BCM. When the BCM wakes up it will then energize the courtesy lamps supply voltage circuit , suppling voltage to the rear compartment courtesy lamp. The rear compartment courtesy lamp switch will provide a ground path for the rear compartment courtesy lamp in order to illuminate the lamp.

UNDERHOOD COMPARTMENT LAMP
When the underhood compartment is opened the underhood compartment lamp illuminates, if the courtesy lamps supply voltage circuit of the BCM is activated (BCM awake).

The underhood compartment lamp illuminates when the courtesy lamps supply circuit of the BCM supplies voltage to the underhood compartment lamp and the underhood compartment switch closes, providing a ground path.