Last Door Closed Locking
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
The last door closed locking function is a vehicle personalization feature that is intended to allow the doors to be locked while passengers are exiting the vehicle. When last door closed locking function is in Active Mode, the body control module (BCM) will delay locking of the vehicle doors for 5 seconds after all of the doors have been closed. The last door closed locking function will be overridden if the BCM receives a door unlock input or a key in ignition input.