For 1990-2009 cars

### Door Lock System Components

The power door lock system consists of the following components:

• | Driver lock/window switch

• | Passenger lock/window door lock switch

• | Door lock actuators in each of the doors

• | Body control module (BCM)

• | PWR/LKS 20A fuse

### Door Lock System Controls

The power door lock system can be controlled by any of the following:

• | A door lock switch LOCK or UNLOCK activation

• | An OnStar® unlock request

• | A keyless entry transmitter activation

• | An automatic door lock activation (Personalization function)

• | An automatic door unlock activation (Personalization function)

• | A delayed locking activation (Personalization function)

### Door Lock Operation

When the driver switch assembly detects a transition of either it’s own door lock switch or the passenger door lock switch to the LOCK position, it switches the door lock actuator lock control circuit to voltage. Since the lock actuator unlock control circuits are at ground potential within the driver switch assembly, the door lock actuator motors transition to the LOCK position.

### Driver Door Unlock Operation

When the driver switch assembly detects a transition of either its own door lock switch or the passenger door lock switch to the UNLOCK position, it switches the driver door lock actuator unlock control circuit to voltage. Since the door lock actuator lock control circuit is at ground potential within the driver switch assembly, the LF door lock actuator motor transitions to the UNLOCK position. The driver lock/window switch contains dedicated control circuits used only for the driver door lock actuator motor. This is done so that only the driver door may be unlocked by using a keyless entry transmitter.

### Passenger Door Unlock Operation

When the driver switch assembly detects a transition of either the driver door lock switch or the passenger door lock switch to the UNLOCK position, it switches the door lock actuator unlock control circuits to voltage. Since the door lock actuator lock control circuit is at ground potential within the driver switch assembly, the door lock actuator motors transition to the UNLOCK position

### Automatic Door Lock/Unlock

The automatic door lock/unlock function is a vehicle personalization feature with the following programmable modes of operation:

1. On vehicles with an automatic transmission, this mode locks all of the doors when the vehicle is shifted out of PARK (P) and unlocks all of the doors when the vehicle is shifted into PARK (P). On vehicles with a manual transmission, this mode locks all of the doors when the vehicle speed is greater than 15 mph (24 km/h) and unlocks all of the doors when the key is removed from the ignition.
2. On vehicles with an automatic transmission, this mode locks all of the doors when the vehicle is shifted out of PARK (P) and unlocks the driver's door when the vehicle is shifted into PARK (P). On vehicles with a manual transmission, this mode locks all of the doors when the vehicle speed is greater than 15 mph (24 km/h) and unlocks the driver's door when the key is removed from the ignition.
3. On vehicles with an automatic transmission, this mode locks all of the doors when the vehicle is shifted out of PARK (P). The doors will not automatically unlock. On vehicles with a manual transmission, this mode locks all of the doors when the vehicle speed is greater than 15 mph (24 km/h). The doors will not automatically unlock.

The automatic door lock function can only be enabled by the BCM if the driver or passenger lock switches are in an Inactive state. For information on programming the automatic door locks, refer to Vehicle Personalization.

### Delayed Locking

The delayed locking function is a vehicle personalization feature that is intended to allow the doors to be locked while passengers are exiting the vehicle. When delayed locking is in Active Mode, the BCM will delay locking of the vehicle doors for 5 seconds after all of the doors have been closed. The delayed locking function will be overridden if the BCM receives a door UNLOCK input or a key in ignition input.

### Lockout Prevention

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 lockout prevention function can be overridden by the BCM, if the BCM receives a remote lock input or if the door is manually locked.

### Unlock After Air Bag Deployment

This feature will unlock all of the vehicle doors 15 seconds after air deployment.

### OnStar® Remote Unlock (RPO AU3 and UE1)

The driver door may be commanded to unlock by a OnStar® request.

### OnStar® Remote Unlock (With RPO UE1, Without RPO AU3)

The vehicle has a driver door lock actuator and unlock relay only, the vehicle is not equipped with a door lock switch and under normal conditions the system functions as a manual lock and unlock system. However, the driver door may be commanded to unlock either by a OnStar request or by a scan tool unlock command.