Power Locks: Description and Operation
POWER LOCKSPower Lock System
The Power Lock System consists of the BCM. RKE Module, and a switch and actuator motor in each door.
Both doors can be locked or unlocked electrically by operating the switch on either front door panel. When the door lock switch is activated, the Body Control Module (BCM) actuates the door lock relay.
Both doors can be locked or unlocked mechanically and independently with their respective locking knobs.
Both doors can be locked or unlocked mechanically from the outside with the key or both 1 locks can be remotely locked or unlocked with the Remote Keyless Entry (RKE) transmitter. The doors can also be unlocked by actuation of the inside remote door handle.
The Body Control Module (BCM) locks or unlocks the doors when an actuation input signal from a door lock switch or Remote Keyless Entry Module (RKE) is received. The BCM signals lock and unlock relays in the Micro Relay Block to actuate the door lock motors. The doors are equipped with actuator motors to lock or unlock the latch mechanisms. The door lock actuator motor is not serviced separately from the door latch. The BCM locks the doors automatically when the vehicle is driven beyond the speed of 25.7 Kph (16 mph). The automatic door lock feature can be disabled if desired. All doors can be locked or unlocked using mechanical button or key cylinder methods.
For Door Lock/Window Switch and Bezel Removal and Installation, (Refer to POWER WINDOWS/POWER WINDOW SWITCH - REMOVAL) and (Refer to POWER WINDOWS/POWER WINDOW SWITCH - INSTALLATION).
Automatic Door Locks
The vehicle comes with two options for power door locks:
- Rolling automatic lock (ENABLE), doors automatically lock at approximately at 29 Kph (18 mph).
- No rolling automatic lock (DISABLE), doors do not automatically lock when the vehicle is moving.
The BCM is equipped with a disable feature to stop the speed sensitive automatic door locks from functioning. The DISABLE feature can be switched ON or OFF as desired. When the system is DISABLED the door locks will operate normally, but will not lock automatically when the vehicle is rolling. When the door locks are ENABLED the door locks will automatically lock when the vehicle is moving at about 29 Kph (18 mph).
Circuit Protection
The BCM controls the door lock relay's operation.
If the door lock switch is actuated continuously for more than one second the BCM will interrupt the relay circuit. The door lock system is protected by a 40 amp fuse located in the Power Distribution Center (PDC) and a fuse in the fuse block. The LOCK and UNLOCK relays are located in the Micro Relay Bank which is located behind and above the glove box. The Power Distribution Center is located on the frame forward of the bulkhead. The lock motors are protected with Positive Temperature Coefficient (PTC) device that prevents motor burn out.
Deck Lid Release
The deck lid is controlled by a remote switch located at the left front corner of the deck lid. The switch operates a relay which is located in the Micro Relay Bank.
The deck lid release function is disabled by the BCM when the vehicle is not in the Park or Neutral position and is moving or when the VTSS is armed.
The deck lid release solenoid is part of the deck lid latch. For replacement, the deck lid latch will need to be replaced.
Door Lock Inhibit
This vehicle has a built in protection against locking the vehicle doors while the keys are in the ignition.
The BCM cancels out the door lock switch actuation, when the key is in the ignition switch and a door is open. After the key is removed from the ignition switch, or the doors are closed, the power door locks will operate normally.
Fig. 2 Key Fob Transmitter:
REMOTE KEYLESS ENTRY MODULE
Remote Keyless Entry (RKE) System
The Remote Keyless Entry (RKE) System allows locking/unlocking of vehicle door(s) by remote control using a hand held Radio Frequency (RF) key fob transmitter.
The key fob transmitter has three buttons to actuate and program the Remote Keyless Entry (RKE) system.
- UNLOCK: Pressing the UNLOCK button once will unlock the driver door, flash the parking lamps one time for 125 millisecond duration, activate the illuminated entry system and disarm Vehicle Theft Security System. Pressing the UNLOCK button twice within five seconds will unlock all doors, flash the parking lamps twice for a 125 millisecond duration, and activate the illuminated entry system. By default, the UNLOCK park lamp flash is shipped enabled.
- LOCK: Pressing the LOCK button locks all doors, flashes the park lamps one time for a 500 millisecond duration, the horn chirp two times, and arms the Vehicle Theft Security System. The chirp/flash verifies the door lock operation. By default, the lock park lamp flash is disabled.
- PANIC: Pressing the PANIC button sounds the horns at half second intervals, flashes the exterior lamps, and turns ON the interior lamps. The panic alarm will remain on for three minutes, or until the PANIC button is actuated again or the ignition switch is turned to the RUN position.
The Remote Keyless Entry Module is capable of retaining the transmitter Vehicle Access Code(s) (VAC) in its memory even after vehicle power has been interrupted.