Door Lock System Components
The power door lock system consists of the following components:
• | Liftgate lock/unlock release switch, if equipped |
• | Driver door unlock relay, w/ keyless entry |
• | Body Control Module (BCM) |
• | Reversible door lock actuators in each of the front doors |
• | Reversible door lock actuator in the side door |
• | Reversible door lock actuator in the cargo door or liftgate |
• | CIG LTR 20A fuse (switch supply voltage) |
• | PWR ACCY 30A circuit breaker (relay supply voltage) |
Door Lock System Controls
The power door lock system can be controlled by any of the following:
• | A power door lock or unlock switch activation |
• | A keyless entry transmission |
• | A BCM delay lock function |
• | A BCM lockout prevention function |
Driver and Passenger Door Lock Operation - w/o Keyless Entry
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 PWR ACCY circuit breaker through the battery voltage
circuit. Voltage is then applied 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.
Driver and Passenger Door Lock Operation - w/ Keyless Entry
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 PWR ACCY circuit breaker through the battery
voltage circuit. Voltage is then applied to the lock side of the door
lock actuators. Since the other side of the passenger door, cargo door
or sliding side lock actuators 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:
• | A keyless entry lock transmission |
Driver and Passenger Door Unlock Operation - w/o Keyless Entry
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 PWR ACCY circuit breaker through the
battery voltage circuit. Voltage is then applied 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.
Passenger Door Unlock Operation - w/ Keyless Entry
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 PWR ACCY circuit breaker through the battery
voltage circuit. Voltage is then applied 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 a keyless entry unlock transmission.
Driver Door Unlock Operation - w/ Keyless Entry
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. The driver door unlock relay
differs slightly from the unlock relay in that the primary side of the
relay is connected to the PWR ACCY circuit breaker 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 PWR ACCY circuit breaker through the battery voltage circuit,
the relay is energized. This causes the contacts to close and complete
the path from the PWR ACCY circuit breaker 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.
Liftgate Lock/Unlock Release Switch Operation
On vehicles equipped with a liftglass and dutch doors, the liftgate
lock/unlock release switch (mechanical key) is added to serve the same
function as the front power door lock switches. By inserting the door
key into the liftgate lock/unlock release switch and turning the key
to the lock or unlock positions, voltage is applied to the door lock
or unlock control circuits to control the lock or unlock relays. This
will lock or unlock all of the doors, including the dutch doors. Once the
door lock system is unlocked, press the liftgate release switch to electrically
open the liftglass and pull the handle to open the secondary latch.
For further information about the liftgate release system, refer to
Rear Hatch/Gate Description and Operation
in Body
Rear End.
Delay Locking Operation
This feature allows the operator to lock all the doors from any door
lock switch or a keyless entry lock transmission with the side door open.
The sliding side door has contact plates that complete the power door
lock and unlock fuse supply circuits when the sliding side door is closed,
and interrupt these circuits when the sliding side door is open. When
a lock function occurs and the BCM senses an active state on the sliding
side door ajar switch signal circuit (door open), the driver, passenger
and cargo doors will lock as described, and the BCM continues to monitor
the sliding side door 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 sliding side door.
Lockout Prevention Operation
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.
Programmable Automatic Door Locks
The automatic door lock feature can be programmed to control the door
lock system. The automatic door lock feature is factory programmed to have
all doors lock and unlock. For detailed instructions on programming the automatic
door locks, refer to
Vehicle Personalization
in Personalization.
When the automatic door lock feature is programmed to control
the door lock system, the BCM will lock the vehicle doors if the following
inputs are true:
• | Ignition 1 input is active. |
• | All door jamb switch inputs are inactive. |
• | Cargo door or lift gate/lift glass ajar inputs are inactive. |
• | Transmission is shifted out of park |
This automatic door lock function will only occur once per ignition
cycle unless, a door jamb switch input changes state to active and back to
inactive. Then the BCM will lock all doors again.
Once the automatic door lock feature has locked the doors, the BCM will
then unlock all the doors when the transmission is shifted into park.