When any of the door lock switches are placed in the lock position, voltage is applied to the door lock control circuit and the lock relay winding. Since the other side of the lock relay winding is connected to ground, the relay is energized. This causes the contacts to close and complete the path from the DR LOCK fuse through the battery voltage circuit. Voltage is then applied through the LOCK fuse to the lock side of the door lock actuators. Since the other side of the all the door lock actuators are connected to the normally closed contacts of the unlock relay to ground , the doors lock.

The lock function can also be accomplished by the BCM supplying voltage to the door lock control circuit by a delay lock function (utilities only).

When any of the door lock switches are placed in the lock position, voltage is applied to the door lock control circuit and the lock relay winding. Since the other side of the lock relay winding is connected to ground, the relay is energized. This causes the contacts to close and complete the path from the DR LOCK fuse through the battery voltage circuit. Voltage is then applied through the LOCK fuse to the lock side of the door lock actuators. Since the other side of the passenger door lock actuator(s) are connected to the normally closed contacts of the unlock relay to ground and the driver door lock actuator is connected to the normally closed contacts of the driver door unlock relay to ground, the doors lock.

The lock function can also be accomplished by the BCM supplying voltage to the door lock control circuit by any of the following:

When any of the door lock switches are placed in the unlock position, voltage is applied to the door unlock control circuit and the unlock relay winding. Since the other side of the unlock relay winding is connected to ground, the relay is energized. This causes the contacts to close and complete the path from the DR LOCK fuse through the battery voltage circuit. Voltage is then applied through the UNLOCK fuse to the unlock side of the door lock actuators. Since the other side of the door lock actuators are connected to the normally closed contacts of the lock relay to ground, the doors unlock.

When any of the door lock switches are placed in the unlock position, voltage is applied to the door unlock control circuit and the unlock relay winding. Since the other side of the unlock relay winding is connected to ground, the relay is energized. This causes the contacts to close and complete the path from the DR LOCK fuse through the battery voltage circuit. Voltage is then applied through the UNLOCK fuse to the unlock side of the door lock actuators. Since the other side of the passenger(s) door lock actuators are connected to the normally closed contacts of the lock relay to ground, the doors unlock.

The unlock function can also be accomplished by the BCM supplying voltage to the door lock control circuit by any of the following:

The driver door unlock control circuit uses a dedicated driver door unlock relay. This is done so that the driver door may be unlocked by itself using a keyless entry unlock transmission or with an automatic door unlock function (if programmed). The driver door unlock relay differs slightly from the unlock relay in that the primary side of the relay is connected to the DR LOCK fuse and the door unlock control circuit is pulled low by the BCM to energize the relay.

When any of the door lock switches are placed in the unlock position, a voltage is applied to the unlock relay and to the BCM. When the BCM senses the voltage signal, it grounds the driver door unlock control circuit. Since the other side of the driver door unlock relay winding is connected to the DR LOCK fuse through the battery voltage circuit, the relay is energized. This causes the contacts to close and complete the path from the DR LOCK fuse through the battery voltage circuit. Voltage is then applied to the unlock side of the driver door lock actuator. Since the other side of the driver door lock actuator is connected to the normally closed contacts of the lock relay to ground, the driver door unlocks.

This feature allows the operator to lock all the doors from the rear lock switch. The rear cargo doors have contact plates that complete the power door lock and unlock fuse supply circuits (among others) when the cargo doors are closed, and interrupt these circuits when the cargo doors are open. When a lock function occurs and the BCM senses an active state on the lift gate ajar switch signal circuit (door open), the driver and passengers doors will lock as described, and the BCM continues to monitor the lift gate ajar switch signal circuit . When the BCM senses an inactive state (door closed), the BCM will cycle the door lock relay again after approximately 5 seconds to perform another lock function, thus locking the cargo door.

This feature prevents the locking of the driver door if the ignition key is left in the ignition lock cylinder. If a lock function occurs from any door lock switch and the BCM senses an active state on either the left front door latch signal, secondary door latch switch signal and/or the lift gate ajar switch signal circuits and the key in ignition switch signal circuit is in the yes state, the BCM will cycle the door lock relay to lock the doors and then cycle the driver door unlock relay to unlock the driver door.