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For 1990-2009 cars only

Power Door Locks Circuit Description Luxury

Driver and Passenger Doors

When a Power Door Lock Switch is operated, all of the doors will LOCK or UNLOCK. Power supplied to the switches comes from the CIG LTR fuse #13 through CKT 640 (ORN). Manual operation of each lock is also possible. The Door Lock Inversion Module receives the lock voltage through CKT 195 (LT BLU) and the unlock voltage through CKT 194 (WHT). The Door Lock Inversion Module changes the voltage signals to ground signals so the Body Control Module (BCM) can read what function is being accomplished. CKT 244 (LT BLU) sends door lock ground signals from the Door Lock Inversion Module to the BCM, and for the unlock signal CKT 245 (DK BLU) completes the connection. Ground for the Door Lock Inversion Module runs through CKT 150 (BLK) to ground G202. Depending on the signal sent from the Door Lock Inversion Module the BCM will determine which door(s) will be locked or unlocked. Unlock voltage is sent to the LF Door Lock Motor through CKT 694 (TAN), Voltage from the BCM for the Passenger Door Unlock function is sent through CKT 781 (ORN/BLK) to the unlock coil of the Door Lock Relay. The relay is ground through CKT 150 (BLK) to ground G202. With the coil energized, power is sent out through CKT 294 (TAN) to the door lock motors, unlocking all but the Driver's Door. For the lock function, the BCM sends voltage through CKT 780 (RED/BLK) to the lock coil of the Door Lock Relay. When the relay is energized power is sent out through CKT 295 (GRY) to all door lock motors, locking the doors.

Rear Cargo Doors

Unlock voltage from the BCM is sent to the Cargo Door Lock Relay through CKT 253 (BRN) which energizes the coil in the relay. Once the Cargo Door Lock Relay is energized, power in through CKT 540 (ORN) contacts with CKT 56 (BLK) sending power to the unlock side of the Rear Cargo Door Lock Motor. The lock function is sent through CKT 295 (GRY) and ground is provided through CKT 294 (TAN), the same as the Driver and Passengers Door Locks. The Cargo Doors must be closed in order for the connection to be complete. The power door lock motor is in the right cargo door. The contactors are on the rear cargo door opening on the body and on the right cargo door.

Power Door Locks Circuit Description Except Luxury

Power Door Lock System Description

The power door lock system incorporates door lock switches on both front doors and on the RH D-pillar, door lock motors in all passenger doors and in the RR cargo door, a door lock relay and a door lock control module.

Power for the door lock switches and the door lock control module is supplied from the CIG LTR fuse 13 through CKT 640 (ORN). Power for the door lock relay is supplied from the PWR ACCY circuit breaker through CKT 540 (ORN). Ground for the door lock relay is supplied from G202 through CKT 150 (BLK) and ground for the door lock control module is supplied from G400 through CKT 150 (BLK).

The door lock motors are reversible and both sides are connected to the normally closed contacts of the door lock relay. Those contacts of the relay are connected to G202. When any of the door lock switches are placed in the lock position, voltage is supplied through CKT 195 (LT BLU) to the relay lock coil. Since the other side of the lock coil is connected to ground, the coil is energized and it pulls the lock contacts closed. Voltage is then supplied through CKT 295 (GRY) to all the door lock motors and the doors lock. The unlock function operates in much the same manner except that when any of the switches are placed in the unlock position, voltage is supplied through CKT 194 (WHT) to the unlock coil of the relay and CKT 294 (TAN) supplies voltage to the apposite side of the door lock motor and the doors unlock.

Door Lock Control Module Description

The door lock control module is used on vehicles equipped with cargo doors. The purpose of the module is to lock the cargo doors after a lock cycle has been commanded from any of the door lock switches with the cargo doors open. When the RH cargo door is open, the module receives a ground signal from the closed contacts of the rear door jamb switch on CKT 1897 (ORN/BLK) to G400. When a lock command is received, the module retains this input until it receives an open input from the rear door jamb switch. Then the module sends a lock command through CKT 194 (WHT) to the door lock relay and the doors lock.

Rear Cargo Doors Description

The power door lock motor will not operate unless the rear cargo doors are fully closed. The power door lock motor is in the right cargo door. The contactors are on the rear cargo door opening on the body and on the right cargo door.