IP Compartment Lamp
WARNING: This page is about a different car, the 2002 Buick Regal and 2002 Buick Century. However, it is still accessible from the selected car via links, so may be relevant.
When the IP compartment is opened the IP compartment lamp illuminates, if the courtesy lamps supply voltage circuit of the BCM is activated (BCM awake).
The IP compartment lamp illuminates when the courtesy lamps supply circuit of the BCM supplies voltage to the IP compartment lamp and the IP compartment switch closes, providing a ground path.