FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.

Door Lock Operation

CIRCUIT OPERATION
When the operator selects the LOCK function, from either switch, voltage is passed through the CLOSED contacts in the switch, through the LOCK resistor to circuit P35. This circuit then connects to the Body Control Module (BCM).

The BCM processes the signal, from circuit P35, and supplies voltage to circuit P38, which connects between the BCM and the LOCK relay located in the junction block. This causes the relay to energize CLOSING the contacts in the relay and connecting circuits F35 and P33. Ground for the coil side of the relay is supplied on circuit Z1, which is spliced in with the door switches, the UNLOCK relay, and terminates at the instrument panel left side cowl.

Circuit F35 is the feed for the contact side of the relay This circuit is protected by a 20 Amp circuit breaker located in the junction block, cavity 23. This circuit breaker is HOT at all times and powered by the A3 circuit. Circuit A3 is protected by a 30 Amp fuse located in cavity H of the Power Distribution Center (PDC).

The P33 circuit is spliced and supplies the voltage from the relay to all the door lock motors. Ground for the door lock motors is supplied on circuit P34. This circuit is spliced and connects from the motors to the UNLOCK relay located in the junction block. The ground circuit is passed through the normally CLOSED contacts in the relay to circuit Z1. Circuit Z1 is spliced in with the LOCK relay, the door switches, and terminates at the instrument panel left side cowl.

On vehicles equipped with Remote Keyless Entry (RKE) the P38 circuit is spliced and connected to the RKE module. If the operator uses the RKE transmitter to LOCK the doors voltage for the coil side of the LOCK relay is provided from the RKE module instead of the BCM.