Power Windows

Power Windows Description and Operation

Power Window System Components

The power window system consists of the following components:

* Driver Door Lock/Window Switch (RPO A31/AN3/DL3)
* Driver window switch (RPO A31 W/O AN3, DL3)
* Passenger Door Lock/Window Switch (RPO A31/AN3/DL3)
* Passenger window switch (RPO A31 W/O AN3, DL3)
* Body Control Module (BCM) (RPO A31/AN3/DL3)
* Rear door power window switches (Extended/Crew Cab)
* Power window motors in each of the doors (circuit breaker protected)
* LT DRS Circuit Breaker
* RT DOORS Circuit Breaker
* Sliding Rear Window Switch
* PWR REAR WNDW Circuit Breaker
* Sliding Rear Window Relays
* Sliding Rear Window Motor

Power Window System Controls (RPO A31/AN3/DL3)

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 driver window control switches are integrated into the driver door lock/window switch. When a power window switch is activated in the up or down positions the driver door lock/window switch supplies power and ground to the window motor control circuits to drive the window motor in the required direction. Prior to activating a power window motor the driver door lock/window switch will supply the control circuit with a low current bias voltage in order to determine that a short to ground condition does not exist and during window motor operation the driver door lock/window switch continues to monitor the motor current to verify proper window motor operation.

The driver door lock/window switch controls the passenger window through a serial data message to the passenger door lock/window switch. When a power window switch is activated in the up or down positions the passenger door lock/window switch supplies power and ground to the window motor control circuits to drive the window motor in the required direction. Prior to activating a power window motor the passenger door lock/window switch will supply the control circuit with a low current bias voltage in order to determine that a short to ground condition does not exist, and during window motor operation the passenger door lock/window switch continues to monitor the motor current to verify proper window motor operation. (Scan tool support is available for this system)

Driver Power Window Operation (RPO A31/AN3/DL3)

The switch for the driver power window has 3 positions Up, Down and Express Down and it's position is a direct input into the driver door lock/window switch. Upon receiving a request for power window operation (switch activation), the driver door lock/window switch supplies voltage to the power window motor up or down circuit and grounds the down or up circuit and the power window motor moves the window UP or DOWN direction.

Front Passenger Power Window Operation (RPO A31/AN3/DL3)

The switch for the front passenger power window has 3 positions Up, Down and Express Down, and it's position is a direct input into the passenger door lock/window switch. Upon receiving a request for power window operation (switch activation), the passenger door lock/window switch 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 operated by using the appropriate switch on the driver door lock/window switch. The window switch on the driver door lock/window switch has 3 positions Up, Down and Express Down and it's position is a direct input into the driver door lock/window switch. Upon receiving a request for front passenger power window operation, the driver door lock/window switch transmits a serial data message indicating the changed switch position. When the passenger door lock/window switch receives this message, the passenger door lock/window switch 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 (RPO A31/AN3/DL3)

The BCM monitors the window UP and DOWN command from the driver door lock/window switch. When the rear window UP or DOWN command is received, the BCM sends a signal to the appropriate rear window switch. The rear window switches continuously monitor the up and down signal circuits, if no function is being commanded, the signal voltage is at approximately B+ voltage. If the UP or DOWN function is commanded, the BCM signal voltage drops approximately 5 volts and the appropriate rear window switch will then command the window in the UP or DOWN direction.

Rear Power Window Lockout Operation (RPO A31/AN3/DL3)

The BCM monitors the window lockout command from the driver door lock/window switch. When the rear window switch operation is authorized, the BCM sends a signal to the rear window switches allowing for normal window operation from the rear switches. If the rear window lockout function is commanded, the BCM signal voltage drops approximately 5 volts which disables the rear window switches and the rear windows will only operate when the BCM receives a command from the driver door lock/window switch. The lockout feature will remain in effect until the ignition switch is cycled or the driver enables the rear windows by pressing the rear window lockout switch again.

Power Window System Controls (RPO A31 W/O AN3, DL3)

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

The driver and passenger door lock and side window switches are integrated control assemblies. The driver and front passenger window switches are normally open, 2 position rocker type switches, with detents for Up and Down. The switches on the driver window switch that control rear passenger window switches are normally open, 2 position rocker type switches, with detents for Up and Down. The driver window switch also has a rear window lockout switch is a push button type switch that provides an active signal to the driver window switch whenever pressed. Whenever the rear window lockout switch is pressed the driver window switch will enable or disable the function of the rear window switches depending on the current state, and illuminate the switch indicator whenever the function is active. (No scan tool support for this system)

Driver Power Window Operation (RPO A31 W/O AN3, DL3)

The switch for the driver power window has 3positions Up, Down and express Down and it's position is a direct input into the driver window switch. Upon receiving a request for power window operation (switch activation), the driver window switch 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 (RPO A31 W/O AN3, DL3)

The switch for the front passenger power window has 2 positions UP and Down and it's position is a direct input into the passenger window switch. Upon receiving a request for power window operation (switch activation), the passenger window switch 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 operated from the driver window switch. The right front switch on the driver window switch has 2 positions Up and Down and its position is a direct input into the driver window switch. Upon receiving a request for front passenger power window operation, the driver window switch transmits a command signal indicating the changed switch position. When the passenger window switch receives this message, the passenger window switch 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 (RPO A31 W/O AN3, DL3)

The rear passenger power windows can also be operated from the driver window switch. The left rear and right rear window switches on the driver window switch has 2 positions, Up and Down, and its position is a direct input into the driver window switch. Upon receiving a request for rear passenger power window operation, the driver window switch transmits a command signal to the appropriate rear window switch which receives this message, the rear window switch then supplies voltage to the power window motor up or down circuit and grounds the down or up circuit and the power window motor runs to move the window up or down.

Rear Power Window Lockout Operation (RPO A31 W/O AN3, DL3)

The rear window lockout function is operated from the driver window switch through a command signal to the rear window switches. When the rear window switches receives an active lockout command, the rear window switches are disabled and the indicator lamp on the lockout switch will illuminate. Once disabled, the lockout feature will remain in effect until the ignition switch is cycled or the driver enables the rear windows by pressing the rear window lockout switch again.

Power Sliding Rear Window

NOTE: Power window lockout switch disables left rear and right rear passenger window switches only and has no effect on the operation of the power sliding window switch.

The power sliding rear window motor is controlled from the rear window OPEN/CLOSE switch through OPEN and CLOSE relays. The OPEN/CLOSE switch is supplied voltage from the body control module (BCM) accessory voltage output circuit. When the switch is pressed in the OPEN or CLOSED position the OPEN or CLOSED relay coil will be supplied accessory voltage and energized through the appropriate relay control circuit. While the OPEN and CLOSE relays are in a de-energized state both motor control circuits will be closed to ground. When one of the relays is energized its motor control circuit will be closed to the battery voltage supply circuit and the other motor control circuit will remain grounded through the de-energized relay.