For 1990-2009 cars

### Door Lock System Components

The power door lock system consists of the following components:

• | Window/door lock/outside rearview mirror switch.

• | DR/LCK relay.

• | PASS DR/UNLCK relay.

• | DRVR DR/UNLCK relay.

• | Body control module (BCM).

• | Reversible door latches in each of the doors.

• | Driver door key cylinder switch

• | Door locks 25A fuse

### Door Lock System Controls

The Power Door Lock System is controlled by the BCM and can be activated by any one of the following:

• | Power door lock switch lock or unlock command

• | Keyless entry lock or unlock command

• | A driver door lock key cylinder switch lock or unlock command

• | Programmed automatic door lock and/or unlock command

• | Lockout prevention command

• | Air bag deployment unlock command

### Door Lock and Unlock Operation

When the door lock switch is activated in the lock or unlock position the BCM will detect a voltage drop on either the door lock switch lock or unlock signal circuits.

The BCM, upon receipt of a lock switch lock or unlock signal, will provide the appropriate relay control circuit with voltage or ground. This will energize the relays. The relay will supply voltage to the door lock actuator lock or unlock control circuits. Since the opposite side of the lock actuator is connected to ground through the other lock actuator control circuit and the normally closed contacts of the lock or unlock relay, the doors will then lock or unlock as commanded.

Three relays are used to operate the door latches, DR/LCK, DR/UNLCK, and DRVR DR/UNLCK relays. The driver door latch is isolated so that only the driver door will unlock by a command from the remote keyless entry transmitter.

### Automatic Door Lock Operation

The doors can be programmed to lock and/or unlock depending upon the owner's preferences:

• | Automatic lock and unlock disabled.

• | Driver door unlock when key is removed from ignition

• | Driver door unlock when the vehicle is shifted into PARK.

• | All doors unlock when key is removed from ignition

• | All doors unlock when the vehicle is shifted into PARK.

• | All doors lock when the vehicle is above 13km/h (8 mph).

• | All doors lock when the vehicle is shifted out of PARK.

### Lockout Prevention Operation

This function is intended to prevent the vehicle operator from locking the doors if the key is left in the ignition and any vehicle door is open. The BCM will react after locking all the doors by unlocking the driver door. The lockout prevention function can be overridden by manually locking the driver door.

### Key Cylinder Unlock and Lock

The BCM will unlock all doors when the key is inserted into the driver door key cylinder and turned to the unlock position for greater than 1 second and lock all doors when the key is turned to the lock position for greater than 1 second.

### Air Bag Deployment Unlock

The BCM will provide unlocking of all the doors 15 seconds after determining the air bags have been deployed.