Sorry Andrew , no BCM on this vehicle . The
Central Security Module is incharge of power door locks .
Central Security Module
For additional information, refer to Section 419-10 .
The central security module is equipped with a battery back-up which holds the programmed transmitter(s) memory in the event of the vehicle battery disconnection.
Principles of Operations
The Door Switch Lock Function
When a door lock switch is moved into the lock position or a door lock cylinder is rotated to the lock position, the door lock switch grounds the lock circuit input to the central security module. The central security module then provides 12 volts to one side of the door lock actuators contained in the door latch unit and simultaneously grounds the other side of the door lock actuators. This completes the door lock actuator circuit, causing the door lock actuators to rotate a cam assembly, which then locks the doors.
The Door Switch Unlock Function
When a door lock switch is moved into the unlock position, the door lock switch grounds the unlock circuit input to the central security module. The central security module then provides 12 volts to the opposite side (relative to locking the door) of the door lock actuator(s) contained in the door latch unit and simultaneously grounds the other side of the door lock actuator(s). This completes the door lock actuator circuit, causing the door lock actuator(s) to rotate a cam assembly in the opposite direction, which then unlocks the door(s). The 12 volts which the central security module provides to the door lock actuator(s) are provided to each door lock actuator from the individual pins on the central security module connector.
Keyless Entry
When a remote transmitter button is depressed, it transmits the appropriate command to the central security module as a radio frequency. The central security module receives the command from the remote transmitter through an antenna, which is incorporated in the central security module.
When the central security module receives a command from the remote transmitter, it then sends the appropriate output to control the desired devices. These outputs devices include:
- The front and rear door lock units.
- Central timer module (CTM).
- The liftgate release motor.
- The right and left side turn signal lamp(s).
The central security module sends a signal to the CTM when courtesy lamp illumination is required.
Computer Operated Locks
Each front door lock actuator contains a bipolar motor that controls the lock and unlock linkage. The lock/unlock lever of both front door interior handles use linkage to actuate the lever lock switch located inside each front door lock actuator. Each lever lock switch remains in the unlock position until lock/unlock lever of the interior door handle is moved to the lock position. This action toggles the lever lock switch to the lock position. The central security module uses only one electrical input for both lever lock switches. The central security module cannot determine whether the driver or passenger door lever lock switch was actuated. Therefore, actuating the lock feature from either front door will have the same affect of locking all doors. Actuating the unlock feature will not unlock any other door.
The door lock control switches for both front doors also use only one input to the central security module.
Both rear passenger doors contain a rear door lock actuator that controls only electric lock or unlock of the door. Actuating the lock/unlock lever at either rear passenger door will have no effect on other doors.
The panic feature of the remote transmitter sounds the vehicle horn when the vehicle is not equipped with anti-theft. If the vehicle is equipped with anti-theft feature, a separate horn is sounds for the panic feature.
