System Operation

The Keyless Entry Power Door Lock system operates to lock or to unlock all doors with the actuation of a single Door Lock Switch or from a remote hand-held radio transmitter operating at 315 Megahertz. Power is available at all times from the PWR ACCY Fuse A through the ORN (540) wire to the Remote Control Door Lock Receiver, the Power Door Lock Relay, the Left Front Power Door Lock Switch, the Right Front Power Door Lock Switch, and the Right Rear Power Door Lock Switch (except cutaway models).

Each of the Door Lock rocker switches have two normally-open contacts. When the upper portion of the switch is depressed to unlock the doors, one contact closes to apply voltage on the WHT (194) wire. This voltage is applied by the WHT (194) wire to the Unlock coil in the Power Door Lock Relay and to the Remote Control Door Lock Receiver. Since the other side of the relay's coils are grounded by the BLK (150) wire at Ground G201 (Base) or at Ground G200 (Upfitter Provisions), the relay coil energizes when voltage is applied. Relay contacts then operate to apply voltage on the TAN (294) wire to the Right and Side Door Lock Motors. At the same time, the WHT (194) wire input to Remote Control Door Lock Receiver causes the Remote Control Door Lock Receiver to energize each of its three outputs. The Driver Door Unlock output is switched from ground to voltage to apply voltage on the TAN (694/294) wire to the Left Door Lock Actuator Motor. Also, the Passenger and Side Door Unlock output switches from ground to voltage to apply voltage on the TAN (294) wire to the Right and Side Door Lock Actuator Motors. Finally, the Rear Door Unlock output switches from ground to voltage to apply voltage on the BLK (1576)/TAN (294) wire to the Rear Door Lock Actuator Motor. The parallel operation of the Right and Side Door Lock Actuator Motors by the Remote Control Door Lock Receiver and the Power Door Lock Relay is to reduce loading on the Remote Control Door Lock Receiver since this branch circuit operates two door lock actuator motors.

The Unlock operation from the Keyless Entry Handheld Transmitter differs in that the transmitter can open the Left Door only, the Rear Door only, or all doors. When the UNLOCK push-button is depressed once on the transmitter, the Remote Control Door Lock Receiver. after verifying the access code, energizes only the Driver Door Unlock output. If the transmitter's UNLOCK push-button is depressed twice within a short period of time, all of the a unlock outputs are energized. If the REAR push-button is depressed, only the Rear Door Unlock output is energized.

Each Door Lock Actuator Motor is connected to the Power Door Lock Relay's Lock contacts by the GRY (295) wire. The de-energized Lock contacts in the Power Door Lock Relay are normally connected to ground. When the Unlock relay operates and the Remote Control Door Lock Receiver's Unlock outputs are energized, voltage is applied to the motors and current flows through the Power Door Lock Relay to ground. The direction of current flow through the motors causes the motors to unlock the doors.

If the unlock operation was initiated remotely, the Remote Control Door Lock Receiver outputs switch from voltage to ground within a short period of time. If the Power Door Lock Switch is held in the unlock position, the outputs to the motors remain energized. Each actuator motor is provided with an internal automatic-reset solid-state circuit breaker. The circuit breaker opens upon excessive current flow for too long. It resets automatically after a period of time when the current flow is stopped. Mechanical restraint at the lock mechanism may cause the circuit breaker to open. It may also open if the switch is held in place too long.

When the lower portion of the Power Door Lock Switch is depressed to lock the doors, the switch contacts closes to apply voltage on the LT BLU (195) wire. This voltage is applied to the Lock coil in the Power Door Lock Relay. The Lock coil energizes and contacts operate to apply voltage on the GRY (295) wire. When the Lock relay operates, its ground connection is broken but the contacts of the Unlock relay remain connected to ground. Also, the unlock outputs from the Remote Control Door Lock Receiver are de-energized and internal contacts are connected to ground. Thus voltage and grounding are applied to each Power Door Lock Actuator Motor and the motors operate in the direction required to lock the doors. Again, parallel paths to ground are provided for the Right and Side Door Actuator Motors.

When the lock command is generated by the actuation of the LOCK (Key Symbol) function on the remote transmitter, the Remote Control Door Lock Receiver generates a voltage on the Lock Signal Output terminal. The voltage on the LT BLU (195) wire energizes the Lock coil in the Power Door Lock Relay and the doors are all locked as described previously for the Power Door Lock Switches.

The Side Door Lock Actuator Motor will not lock the door if the door happens to be open. Logic is provided by the Power Door Lock Control Module to lock the side door after it is closed. With the side door open, actuation of the Lock function will lock the front and rear doors immediately. However, the Side Door Lock Actuator Motor will not operate because the contacts at the Side Door Contact Plate are open. However, the Lock command is represented as a voltage on the LT BLU (195) wire to the Power Door Lock Control Module. The Power Door Lock Control Module senses that the Side Door is open by the grounded signal from the Side Door Jamb Switch on the WHT/BLK (l58) wire. When the Side Door is open and the Lock command is observed, the control module enables the delayed operation of the power door locks. It waits for the Side Door Jamb Switch to open with the closure of the Side Door. With the door closed, a timer is set and starts timing. After approximately five seconds, the Power Door Lock Control Module produces another Lock command. The voltage on the LT BLU (195) wire actuates the Power Door Lock Relay to operate all Power Door Lock Actuator Motors to lock the doors. Since the side door is now closed, contact is made through the Side Door Contact Plate and the Side Door Locks.

If, during the five second delay, the Side Door is again re-opened, the Power Door Lock Control Module will remain enabled and waits for the side door to close again. It will lock the Side Door five seconds after it closes. However, if while the door is open or if while in this five second delay, the Unlock command is generated at any Power Door Lock Switch, the Power Door Lock Control Module will be disabled. It will not lock the Side Door when it closes.

The Date Link Connector for the Remote Control Door Lock Receiver is grounded during the re-programming of the module for a new transmitter.