Operation CHARM: Car repair manuals for everyone.

Driver and Passenger Door Lock Operation

When any of the door lock switches are placed in the lock position, voltage is applied to the door lock control circuit and the lock relay winding. Since the other side of the lock relay winding is connected to ground, the relay is energized. This causes the contacts to close and complete the path from the PWR LKS fuse through the battery voltage circuit. Voltage is then applied to the lock side of the door lock actuators. Since the other side of the passenger door lock actuator(s) are connected to the normally closed contacts of the unlock relay to ground and the driver door lock actuator is connected to the normally closed contacts of the driver door unlock relay to ground, the doors lock.

The lock function can also be accomplished by the BCM supplying voltage to the door lock control circuit by any of the following:
^ A keyless entry lock transmission
^ A delay lock function (utilities only)