Keyless Entry Interior Illumination
WARNING: This page is about a different car, the 2003 Pontiac Sunfire and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
When the body control module (BCM) receives a door unlock command from the remote keyless entry (RKE) transmitter, the BCM will keep the courtesy lamps on approximately 20 seconds and then turn them off through the theater dimming feature. If the door locks are activated to the LOCK position, the courtesy lamps will deactivate immediately. When the ignition switch is turned to the ON position the courtesy lamps will deactivate in approximately one second.