GM Service Manual Online
For 1990-2009 cars only

When you activate a door lock switch in the power lock system, all of the doors will lock or unlock in unison. You may operate each lock manually. The locks operate by reversible motors. The door lock switches operate the motors by performing the following actions:

    • The switches apply voltage to one of the terminals.
    • The switches apply ground to the other terminal.

Battery voltage is applied to both door lock switches at terminal F. When you move the left door lock switch to LOCK, battery voltage is applied to both door lock motors from CKT 295. Both motors are grounded through the following components to ground 302:

    • CKT 294
    • The contacts of the left door lock switch
    • CKT 194
    • The contacts of the right door lock switch
    • CKT 250

When you move the left door lock switch to UNLOCK, battery voltage is applied to all door lock motors in the opposite direction from CKT 294. Both motors are grounded through the following components to ground 302:

    • CKT 295
    • The contacts of the left door lock switch
    • CKT 195
    • The contacts of the right door lock switch
    • CKT 250

When you move the right door lock switch to LOCK, battery voltage is applied to both door lock motors from the following components:

    • CKT 195
    • The contacts of the left door lock switch
    • CKT 295

When you move the right door lock switch to UNLOCK, battery voltage is applied to all door lock motors in the opposite direction from the following components:

    • CKT 194
    • The contacts of the left door lock switch
    • CKT 294

During right door lock switch operation, both motors are grounded through the following components to ground 302:

    • CKT 295
    • The contacts of the left door lock switch
    • CKT 195
    • The contacts of the right door lock switch
    • CKT 250