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For 1990-2009 cars only

Power Door Lock Components

The power door lock system consists of the following components:

    • Driver door lock switch
    • Passenger door lock switch
    • Driver door switch assembly (DDSA)
    • Driver door module (DDM)
    • Passenger door module (PDM)
    • Left rear door module (LRDM)
    • Right rear door module (RRDM)
    • Driver door lock actuator
    • Passenger door lock actuator
    • Left rear door lock actuator
    • Right rear door lock actuator
    • Driver door cylinder unlock switch
    • Class 2 serial data circuit
    • Power door serial data circuit
    • DRVMDL 10 amp fuse, DDSA and DDM logic, DDM internal driver operation
    • PASS MDL 10 amp fuse, PDM logic and internal driver operation
    • RRDR MDL 10 amp fuse, LRDM and RRDM logic and internal driver operation

Door Lock System Controls

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

    • A power door lock switch activation
    • A keyless entry transmission
    • A driver door key cylinder unlock switch activation
    • An automatic door lock function

Power Door Lock Operation

The vehicle is equipped with power door locks. Each lock actuator is powered and controlled by the door module mounted in the individual door. The driver door module (DDM) is the master control for the door lock system but the rear integration module (RIM) determines when the lock functions are permitted.

The front passenger door interior lock switch is wired to the front passenger door module (PDM). The driver door interior lock switch is wired to the driver door switch assembly (DDSA). Interior lock switches are not provided for the rear doors. The DDSA and the PDM send the lock switch requests to the DDM over the power door serial data circuit. The DDM then sends the lock requests to the RIM over the Class 2 serial data circuits.

The door lock operation modes are controlled by the RIM. The RIM examines the requested lock switch requests from the DDM or the remote function actuator (RFA). The RIM also examines the transmission shift selector position and ignition switch position information available over the Class 2 serial data circuits. If the RIM determines that a lock or unlock function is permitted, it sends a class 2 message back to the DDM commanding the DDM to perform that function. The DDM then locks or unlocks the driver door, and sends commands to the rest of the door modules, via the power door serial data circuit, to lock or unlock their respective doors.

Door Modules Power and Ground

In order to control power door lock operations, as well as other door functions, door modules must be powered up. For this purpose, battery voltage is supplied from the rear fuse block, through separate circuits, to each door module. Each door module is separately grounded through a ground stake. The door modules also use these voltage and ground supplies to provide power and ground to their associated lock actuators and lock switches. The rear doors, however, are not equipped with lock switches. In addition, the front door modules use these voltage and ground supplies for outside rearview mirror operations.

The DDSA battery voltage circuit is fed, through the DDM, by the DRVMDL 10 amp fuse located in the Rear Fuse Block.

The DDM battery voltage circuit is fed by the DRVMDL 10 amp fuse located in the Rear Fuse Block.

The PDM battery voltage circuit is fed by the PASS MDL 10 amp fuse located in the Rear Fuse Block.

The LRDM and RRDM battery voltage circuits are both fed by the RRDR MDL 10 amp fuse located in the Rear Fuse Block.

These circuits are in the C1 harness connector of each door module and must not be confused with the door modules voltage and ground circuits that are used exclusively to drive the power window motors.

Front Passenger Door Power Lock Switch

In order to receive a signal from its associated door lock switch, the front passenger door module supplies battery positive voltage and ground to the contacts of the switch. Their are two circuits for battery positive voltage, one for a lock signal, and one for an unlock signal. The module supplies ground to the switch via a third circuit. When the switch is activated for a lock or unlock function, the contacts for that function are closed to ground and voltage flows through the switch, providing the module with the neccessary signal input.

Driver Door Power Lock Switch

The driver door lock switch is similar to the passenger door lock switch, but it is wired to the driver door switch assembly (DDSA), and, for a ground circuit, to the driver door module (DDM). It also works the same way as the passenger lock switch works, but the lock switch signal input information is detected and processed by the DDSA. The DDSA has two circuits that supply 5 volts to the contacts of the driver door lock switch, one for a lock signal, and one for an unlock signal. The driver door lock switch ground circuit is provided by the DDM. When the lock switch is activated to lock or unlock, the contacts for that function are closed to ground, the voltage flows through the switch and is detected by the DDSA. The DDSA then relays the lock switch information to the driver door module via the power door serial data circuit.

Power Door Lock Motors

Each door module supplies battery positive voltage and ground, through the door lock actuator motor control circuits to its associated door lock actuator motor. The power door lock motors are reversible. The function performed by the lock motor, Lock or Unlock, depends on which motor control circuit the voltage is applied to, and which motor control circuit the ground is applied to. To perform a lock function, the door module applies battery voltage to the door lock motor Lock circuit, and ground to the door lock motor Unlock circuit. To perform an Unlock function, the door module reverses the polarity, applying battery voltage to the door lock motor Unlock circuit, and ground to the door lock motor Lock circuit.

Automatic Door Locks

The automatic door lock system provides for locking or unlocking all or one of the doors when shifting the transmission in and out of PARK, or, when turning the ignition key to the OFF position. This system is commanded according to the information stored in the rear integration module (RIM). The RIM receives the features selected by the driver from the driver information center (DIC). The RIM commands the driver door module (DDM) which in turn commands the individual passenger door modules. For customized selections available and programming instructions, refer to: Personalization Description and Operation in Personalization.

Anti-Lockout feature

Leaving the key in the ignition with any door open will disable the use of the power door locks and the Remote Keyless Entry (RKE) lock function.

The anti-lockout feature can be overridden by holding the lock switch in the LOCK position for more than 3 seconds.

Central Door Unlock

The central door unlock feature provides a way to unlock all of the passenger doors while using the door key to unlock the driver door. The feature is controlled by the driver door module (DDM), the driver door lock cylinder, and the driver door cylinder switch, which is an integral part of the driver door lock actuator.

The driver door lock cylinder, which is mounted to the exterior of the driver door, is connected to the driver door cylinder switch by means of a mechanical rod. In order to receive the neccesary signal from the driver door cylinder switch, the DDM supplies battery voltage, through the door key switch signal circuit, and ground through the ground circuit, to the normally open contacts of the switch. When the door key is inserted into the driver door lock cylinder and turned to the Unlock position, the contacts of the driver door cylinder switch close, voltage from the DDM flows through the switch, and the DDM recognizes the voltage flow as a signal input. The DDM determines that a central door unlock request has been made when either one of the following switch activation methods is used:

    • The driver door cylinder switch contacts are continuously closed for longer than 3 seconds.
    • The driver door cylinder switch contacts are closed twice in 3 seconds.

The DDM sends a Class 2 message to the rear integration module (RIM) indicating either one of the above activations. The RIM sends a Class 2 message to the DDM to unlock all doors. The DDM sends a power door serial data message to the other door modules to unlock their respective doors.

Delayed Locking feature

This personalization feature permits the delay of all door locking until 5 seconds after the last door is closed. This feature is controlled by the rear integration module (RIM) which operates based on data received over the Class 2 serial data circuits.

  1. When the lock function is requested, either by the remote function actuator (RFA) or the driver door module (DDM) while the drivers door is open and the ignition key is removed from the ignition, the RIM commands the radio, via the Class 2 serial data circuit, to sound the chime 3 times to signal that the delayed locking is active.
  2. When the DDM detects that the driver door is closed, and receives the message from the other door modules that their respective doors are also closed, it sends a Class 2 message to the RIM.
  3. The RIM waits for 5 seconds, then sends the Class 2 message to the DDM to lock the doors. The DDM locks the driver door and sends the power door serial data message to the passenger door modules to lock their respective doors.

If any door is opened during the 5 second delay period, the RIM resets the timer and waits until it again receives the doors closed message from the DDM to restart the delay period.

Pressing a power lock switch on any door or on the remote transmitter for the RFA causes the RIM to override this feature and lock all doors immediately.

To program the delayed locking feature, refer to Personalization Description and Operation in Personalization.