Key Cylinder Unlock
WARNING: This page is about a different car, the 2002 Chevrolet Monte Carlo, 2002 Chevrolet Impala, 2001 Chevrolet Monte Carlo, and 2001 Chevrolet Impala. However, it is still accessible from the selected car via links, so may be relevant.
BCM will provide unlocking of all doors when either driver or front passenger key cylinder switch is actuated to the UNLOCK position for longer than one second.