Power Locks: Description and Operation
INTRODUCTIONAll doors can be locked or unlocked electrically by operating the switch on either front door panels. When the door lock switch is activated the Body Control Module actuates the door lock relay.
All doors can be locked or unlocked mechanically and independently with their respective locking knobs.
The right and left front door can be locked or unlocked mechanically from the outside with the key. The front doors can also be unlocked by actuation of the inside remote door handle.
The deck lid can be unlatched by either depressing the push switch from inside the car, manually by key from outside or by depressing the remote keyless entry deck lid release button two times.
SYSTEM OPERATION
The Body Control Module (BCM) actuates the power door lock relays when a door lock switch is activated. If the door lock switch is pressed for longer than eight consecutive seconds, the BCM will de-energize the door lock relay.
The door lock switches provide a variable amount of voltage through the multiplexed (MUX) circuit to the BCM Depending upon that input and various conditions that must be met (i.e., door lock inhibit, etc.). the BCM will determine the action to be taken and activate the proper relay for approximately 250 to 350 mil sec..
The system includes an Automatic Door Locking feature. The vehicle is built with the system disabled. When the system is disabled the door locks will work by use of the door lock switches and the Remote Keyless Entry System only When the Automatic Door Lock System is enabled the BCM will automatically lock all the doors when all of the conditions below are met:
^ All doors are closed
^ The vehicle speed exceeds 15 ± 1 mph
^ The throttle position sensor tip-in is greater than 10 ± 2 degrees
The scan tool (DRB) is used to enable/disable the automatic door lock system. Refer to the proper Body Diagnostic Procedures for the procedure.
The Body Control Module will automatically re-lock all doors if the above conditions are met and if any of the doors become ajar and then closes again.
The power lock motors are also equipped with a thermal protection system which prevents the motors from burning out. The motors may chatter if they are continuously activated.
Other power door lock features:
Child Protection Lock-The child protection locks are on the rear doors only. The lock when engage, will disable the inside door handle from opening the door. The lock is part of the latch/lock assembly. The lock is engaged by moving a lever that is located on the rearward inside edge of the door.
RKE (Remote Keyless Entry) - This feature allows locking and unlocking of the vehicle door(s) by remote control using a hand-held transmitter to activate a radio receiver (RKE module). If the vehicle is equipped with vehicle theft security system, it will also arm or disarm that system. The transmitter can also unlock the trunk while the vehicle is in park and the ignition off. The system was changed in model year 1995 requiring the trunk release button to be pressed twice to prevent accidental opening of the trunk. The module is capable of retaining two (2) transmitter codes. To program the transmitter see Body and Frame/Locks/Keyless Entry.
Door Lock Inhibit - With the key in the ignition switch and the driver's door open, the Body Control Module (BCM) will ignore the command to lock the power door lock. This protects against locking the vehicle with the keys still in the ignition. The unlock switches are still functional. Once the key is removed and the driver's door is closed, the BCM will allow the power door locks to lock.
Illuminated Entry-The Illuminated Entry System is available on vehicles equipped with the Remote Keyless Entry system. The Illuminated Entry System turns ON the courtesy lamps (except ignition key halo lamp) when the remote keyless entry system is activated. The Remote Keyless Entry Module and the Body Control Module (BCM) are used to control the system. Courtesy lamps will turn on for 30 seconds (±1 second) and "fade-to-OFF" over a five second period.
The Illuminated Entry System also turns ON the courtesy lamps (and ignition key halo lamp) when a door is opened. The courtesy lamps will remain ON while the door is open, then "fade-to-OFF" 30 seconds (±1 second) after the last door is closed.
The courtesy and ignition key halo lamps will "fade-to-OFF" immediately when the ignition is switched to ON.
The Illuminated Entry System cannot be activated during the 30 second (±1 second) period after the ignition switch is turned OFF. If a door is opened and closed during this 30 second period, the system will function as previously described.
If the battery voltage is interrupted to the Illuminated Entry System, the system will not function until the Remote Keyless Entry UNLOCK function is actuated.