Remote Keyless Entry Exterior Lamp 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 then flash the headlamps twice. With all the doors closed, and the RKE transmitter is used to lock the doors, the head lamps will flash once. The headlamps will not flash if the rear compartment is opened using the RKE transmitter.