Driver Door Unlock Operation
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.
When BCM detects a transition of either of the door lock switches to UNLOCK position, it switches driver door lock actuator unlock control circuit to voltage. Since door lock actuator lock control circuit is at ground potential within BCM, left front door lock actuator motor transitions to UNLOCK position.
Driver door lock actuator unlock control circuit is a dedicated control circuit used only for driver door lock actuator motor. This is done so that driver door may be unlocked by itself using a keyless entry transmitter or an automatic door unlock function (if programmed).