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Door & Component Operation Descriptions (03-06)

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Power Door Locks Description and Operation

Door Lock System Components


The power door lock system consists of the following components:

-The driver door module (DDM)
-The passenger door module (PDM)
-The body control module (BCM)
-The driver information center (DIC)
-The rear door lock switch
-The door lock relay
-The door unlock relay
-The liftgate lock relay--utility vehicles with liftgate only
-The reversible door lock actuators in each of the doors and liftgate
-LOCKS 20A fuse (rear lock/unlock relay supply voltage)
-ECC 10A fuse (liftgate lock 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
-An automatic door lock function
-A delay lock function
-Door lock cylinder switch activation
-Lockout Prevention
-An airbag deployment


Driver, Passenger and Cargo Door Lock System Operation

The front power door lock switches are integral components of the driver door module (DDM) and passenger door module (PDM). The switches are two position normally open rocker switches. When placed in either the lock or unlock positions, the switches provide a direct input to the DDM or PDM. The DDM or PDM monitors these inputs and sends a Class 2 message indicating a change in the switch's respective position. Modules which activate the power door lock motors receive the Class 2 message and activate the motor in the appropriate direction to lock or unlock the vehicle's doors and liftgate. The rear door lock switch provides a lock and unlock signal to the body control module (BCM). The BCM upon receipt of a lock or unlock signal will control the rear door lock relays and also send a Class 2 message to the DDM and PDM to perform the appropriate function.

The modules which activate the power lock motors are:

-The DDM (driver door lock actuator).
-The PDM (passenger front door lock actuator).
-The BCM (both rear door lock actuators and cargo door/liftgate).

The DDM and PDM are directly connected to the respective door lock actuator through the door lock motor lock and unlock circuits. Once a door lock or unlock request has been received, the module will supply battery voltage to one side of the actuator and ground the other causing the doors to lock or unlock.

The rear passenger and cargo doors differ slightly in that they use lock and unlock relays. The relays supply and coil sides receive a constant voltage through the battery voltage supply circuit. The normally closed contacts are connected to ground and the control side is connected to the BCM. Once a door lock or unlock request has been received by the BCM, the BCM will ground the control side of the appropriate relay. This energizes the relay and allows voltage to be applied to either the door lock motor lock or unlock circuits. since the other side of the door lock actuator is connected to the normally closed contacts of the opposing relay to ground, the doors lock or unlock.

 
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 driver door module (DDM), passenger door module (PDM) and body control module (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 liftgate/liftglass 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 DDM, PDM and 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.


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 body control module (BCM) senses an active state on either the left front door latch signal, secondary door latch switch signal and/or the liftgate ajar switch signal circuits and the key in ignition switch signal circuit is in the YES state, the BCM, driver door module (DDM) and passenger door module (PDM) will lock the doors and then the DDM will unlock the driver door.


Delayed Locking Operation

With any door open and a door lock switch is activated in the lock position, the driver door module (DDM), passenger door module (PDM) and the body control module (BCM) will go into a lock pending state. The BCM will also give three audible chimes. When the door is closed, the DDM, PDM and the BCM will lock the doors after approximately five seconds. This feature can be overridden by activating the door lock switch a second time and the doors will lock even with a door open.


Unlock After Air Bag Deployment

This feature will unlock all of the vehicle doors 15 seconds after an air bag deployment.
 
Power Windows Description and Operation


Power Window System Components

The power window system consists of the following components:

-Driver Door Module (DDM)
-Passenger Door Module (PDM)
-Body Control Module (BCM)
-RR power window switch
-Window up and window down relays in each of the rear passenger window switches
-Window lockout switch
-Reversible power window motors in each of the doors (circuit breaker protected)
-LT DOOR CB 25A (System power for left windows)
-RT DOOR CB 25A (System power for right windows)


Power Window System Controls

The power window system will operate anytime the Retained Accessory Power (RAP) system is active or when the ignition switch is in the ACCY or ON position.

The DDM contains four power window switches which are integral components. Closing any of the normally open, rocker type switches provides the DDM with a request for power window operation. The switches for the two front windows have three positions UP, Down and Express Down, while the switches for the rear windows have only two positions, UP and Down. Each of these switches and their positions is a direct input into the DDM. Upon receiving a request for power window operation, the DDM, transmits a Class 2 message indicating the switch and it's changed position.

The PDM contains a single power window switch that is an integral component. Closing of this normally open, rocker switch provides the PDM with a request for the front passenger power window operation. The switch for the front passenger window has two positions Up and Down. Each of these switch positions is a direct input to the PDM.

The two rear passenger doors have there own switches. Each of the switches contain a power window up and down relay. A switch activation alone can control the up and down functions of the rear windows. However the BCM, upon receiving a Class 2 message from the DDM, can control the set of relays which will activate the rear window motors.


Power Window Motor Operation

A permanent magnet motor operates each of the power side windows. Each motor raises or lowers the glass when the motor receives voltage. The direction the motor turns depends on the polarity of the supply voltage. The power window switches control the polarity of the supply voltage. A built-in circuit breaker protects each motor. The circuit breaker opens when the switch is depressed for a extended period of time under the following conditions:

-The window has an obstruction.
-The window is fully open or fully closed.

The circuit breaker will reset automatically as the circuit breaker cools.


Driver Power Window Operation

The switch for the driver power window has three positions UP, Down and Express Down and its position is a direct input into the DDM. Upon receiving a request for power window operation (switch activation), the DDM supplies voltage to the power window motor left front up or down circuit and grounds the opposite and the power window motor runs to move the window up or down.


Front Passenger Power Window Operation

The switch for the front passenger power window has two positions UP and Down, and its position is a direct input into the PDM. Upon receiving a request for power window operation (switch activation), the PDM supplies voltage to the power window motor right front up or down circuit and grounds the opposite and the power window motor runs to drive the window up or down.

The front passenger power window can also be controlled from the power window master switch. The power window master switch for the front passenger power window has three positions UP, Down and Express Down and its position is a direct input into the DDM. Upon receiving a request for front passenger power window operation (switch activation), the DDM transmits a Class 2 message indicating the changed switch position. When the PDM receives this message, the PDM supplies voltage to the power window motor right front up or down circuit and grounds the opposite and the power window motor runs to move the window up or down.


Rear Passenger Power Window Operation

The passenger power window switches incorporate window up and down relays. The supply side of all the window up and down relays receive voltage through the battery voltage supply circuit and the LT DOOR or RT DOOR circuit breakers respectively. The normally closed contacts of each relay is connected to ground. The load side of each of the relays are connected to either side of the power window motor through the power window up and down circuits. The relay coil feed circuits are connected to the BCM through the power window lockout control circuit and the relay control circuits are connected to the power window switches and to the BCM.

If a rear power window switch is placed in the down position, the down relay would energize and allow battery voltage to the power window motor through the power window motor down circuit. Since the opposite side of the motor is connected to the normally closed contacts of the up relay to ground through the power window motor up circuit, the window moves down. If a rear power window switch is placed in the up position, the up relay would energize and allow battery voltage to the power window motor through the power window motor up circuit. Since the opposite side of the motor is connected to the normally closed contacts of the down relay to ground through the power window motor down circuit, the window moves up.

The rear passenger power windows can also be controlled from the power window master switch. The power window master switches for the rear passenger power windows have two positions UP and Down and its position is a direct input into the DDM. Upon receiving a request for rear passenger power window operation (switch activation), the DDM transmits a Class 2 message indicating the changed switch position. When the BCM receives this message, the BCM can control the rear window up and down relays.


Express Down Operation

The express down function controls both the driver and front passenger power windows but only from the driver door power window master switch. When either the driver or front passenger window switch is momentarily depressed to the express down position, it is a direct input into the DDM. If the request was for the driver power window, the DDM supplies voltage to the power window down circuit continuously until the power window reaches the bottom of its travel. At this point, the DDM senses an over current situation on the power window down circuit and interrupts the voltage supply. If the request was for the front passenger power window, the DDM transmits a Class 2 message indicating an express down function was requested. When the PDM receives this message, the PDM supplies voltage to the power window down circuit continuously until the power window reaches the bottom of its travel. At this point, the PDM senses an over current situation on the power window down circuit and interrupts the voltage supply.


Power Window Lockout Operation

The DDM contains a window lockout switch that is responsible for the disabling of all the passenger windows from the individual passenger window switches. When the window lockout switch is activated, the DDM transmits a Class 2 message indicating that a window lockout request has been received. When the PDM receives this message, it will disable the power window motor up and down circuits. When the BCM receives this message, it will interrupt the up and down relay coil feed voltage for both rear doors. Once activated, the lockout feature will remain in effect until the ignition switch is cycled or the DDM receives another power window lockout switch activation.

 
Door Ajar Indicator Description and Operation


Door Ajar Indicator System Components

The door ajar indicator system consists of the following components:

-The driver door module (DDM)
-The passenger front door module (PDM)
-The body control module (BCM)
-The instrument panel cluster (IPC)
-The driver information center (DIC)
-The driver door ajar switch
-The passenger door ajar switch
-The left rear door ajar switch
-The right rear door ajar switch


Driver Door Ajar And Passenger Door Ajar

The DDM and PDM receive a discrete input from the respective door ajar switch to indicate the status of the door. The DDM or PDM then communicates this status to the IPC via class 2 message. The IPC, upon receipt of this class 2 message, will illuminate the appropriate door ajar message in the DIC and also send a class 2 message to the radio to activate the door ajar audible warning when the following conditions are met:

-The transmission is removed from PARK
-The vehicle speed is greater then 8.05 km/h (5 mph)


Left Rear Door Ajar And Right Rear Door Ajar

The BCM receives a discrete inputs from both the left and right rear door and liftgate ajar switches to indicate the status of the doors and liftgate. The BCM then communicates this status to the IPC via class 2 message. The IPC, upon receipt of this class 2 message, will illuminate the appropriate door ajar message in the DIC and also send a class 2 message to the radio to activate the door ajar audible warning when the following conditions are met:

-The transmission is removed from PARK
-The vehicle speed is greater then 8.05 km/h (5 mph)
 
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