Door Lock System Components
The power door lock system consists of the following components:
|     •  | Rear door lock switch (utilities only) | 
 
|     •  | Driver door unlock relay (uplevel vehicles) | 
 
|     •  | Body Control Module (BCM) | 
 
|     •  | Reversible door lock actuators in each of the doors | 
 
|     •  | MIR/LOCK 3A fuse (switch supply voltage) | 
 
|     •  | DR LOCK 20A fuse (relay supply voltage) | 
 
|     •  | UNLOCK 15A fuse (unlock supply voltage) | 
 
|     •  | LOCK 15A fuse (lock supply voltage) | 
 
|     •  | UNLOCK JMPR (base vehicles) | 
 
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 (uplevel vehicles) | 
 
|     •  | An automatic door lock function | 
 
|     •  | A delay lock function (utilities) | 
 
Driver and Passenger Door Lock Operation (Base Vehicles)
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 during a delay lock function (utilities only).
Driver and Passenger Door Lock Operation (Uplevel Vehicles)
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:
|     •  | A keyless entry lock transmission | 
 
|     •  | An automatic door lock function (if programmed) | 
 
|     •  | A delay lock function (utilities only) | 
 
Driver and Passenger Door Unlock Operation (Base Vehicles)
When any of the door lock switches are placed in the unlock position, voltage
is applied to the door unlock control circuit and the BCM.  When the    BCM senses
the voltage signal, it grounds the door unlock control circuit    and the unlock relay
winding. 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 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.
Passenger Door Unlock Operation (Uplevel Vehicles)
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 and the
BCM. 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.
The unlock function can also be accomplished by the BCM supplying voltage to
the door lock control circuit during any of the following:
|     •  | A keyless entry unlock transmission | 
 
|     •  | An automatic door unlock function (if programmed) | 
 
Driver Door Unlock Operation (Uplevel Vehicles)
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 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    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.
The unlock function can also be accomplished by the BCM supplying voltage to
the door lock control circuit during any of the following:
|     •  | A keyless entry unlock transmission | 
 
|     •  | An automatic door unlock function (if programmed) | 
 
Delay Locking (Utility Vehicles)
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.
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
The automatic door lock option is factory programmed to have no doors lock or
unlock. The automatic door lock feature can be programmed to control   the door lock
system based on the following inputs:
|     •  | Ignition 1 input is active. | 
 
|     •  | All door jamb switch inputs are inactive. | 
 
|     •  | Cargo door or lift gate/lift glass adjar inputs are inactive. | 
 
|     •  |  Vehicle speed is greater than 24 km/h (15 mph) for 2 seconds. | 
 
An automatic door lock function will only occur once per ignition cycle unless,
any door jamb switch input changes state to active and back    to   inactive. Then
the automatic door lock feature will lock all doors again.
Once the automatic door lock feature has locked the doors, the automatic door
lock feature will then unlock all the doors once the ignition key is   removed from
the ignition.
For detailed instructions on programming the automatic door locks, refer to 
Vehicle Personalization 
  in Personalization.