Door Lock System Components
The power door lock system consists of the following components:
|     •  | Left front door lock switch | 
 
|     •  | Right front door lock switch | 
 
|     •  | Endgate/liftgate lock cylinder switch (utilities only) | 
 
|     •  | Driver door unlock relay | 
 
|     •  | Body Control Module (BCM) | 
 
|     •  | Reversible door lock actuators in each of the doors | 
 
|     •  | MIR/LOCK 3A fuse (switch supply voltage | 
 
|     •  | PWR LKS15A fuse (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 (if equipped) | 
 
Driver and Passenger Door Lock Operation
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 LKS fuse 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 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:
|     •  | A keyless entry lock transmission | 
 
|     •  | A delay lock function (utilities only) | 
 
Driver Door Unlock Operation
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 coil side of the
relay   is connected   to the PWR LKS fuse and the door unlock control circuit
is   pulled to ground  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 LKS fuse through the battery voltage circuit, the relay is
energized.       This causes the contacts to close and complete the path from
the PWR  LKS  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.
The unlock function can also be accomplished by the BCM supplying voltage
to the door lock control circuit during a keyless entry unlock transmission.
Passenger Door Unlock Operation
When any of the door lock switches are placed in the unlock position,
voltage is applied to the door unlock control circuit. The door unlock control
  circuit supplies voltage to the unlock relay winding and the BCM. Since
the   other side of the unlock relay  winding  is connected to battery voltage,
  the relay is energized. This causes the contacts  to close and   complete
   the path from the PWR LKS fuse 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 during a keyless entry unlock transmission.
Lockout Prevention
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-Manual Transmission
The automatic door lock feature can be programmed to control the door
 lock system. The automatic door lock feature is factory programmed to have
   no doors lock or unlock. For detailed instructions on programming the automatic
   door locks, refer to   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. | 
 
|     •  |  Vehicle speed is greater than 24 km/h (15 mph)
 for 2 seconds. | 
 
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 once the ignition key is removed from the ignition.
Programmable Automatic Door Locks-Automatic Transmission
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   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.