The vehicle is equipped with power windows controlled by the door modules. Each passenger door window can be operated, either from a power window switch built into the driver door switch assembly (DDSA), or from a power window switch mounted locally to the associated door. The driver door window can be operated only from the driver door power window switch built into the DDSA. When a window is operated from the DDSA, the DDSA interprets the window switch signal. When a window is operated from a passenger door window switch, the associated passenger door module interprets the window switch signal.

When any window is operated from the DDSA, the DDSA examines the switch input and sends the information to the driver door module (DDM) via the power door serial data circuit. The DDM checks to see if it has received any class 2 serial data messages from any of the other vehicle modules (i.e. ignition switch position) prohibiting the movement of the window. If the window being operated is the driver door window, and if no prohibitive class 2 messages have been received, the DDM then applies voltage and ground to the driver door window motor to move the window glass as requested. If the window being operated is a passenger door window, and if no prohibitive class 2 messages have been received, the DDM sends the request, via the power door serial data circuit, to the appropriate passenger door module. The passenger door module then applies voltage and ground to the associated passenger door window motor to move the window glass as requested.

When a passenger door window is operated from the power window switch mounted locally to its associated door, the passenger door module examines the switch input and checks to see if the DDM has received any class 2 serial data messages prohibiting window operation. If there are no prohibitive messages, the passenger door module powers the associated passenger door window motor.

Both front door windows have the express down feature. This allows the front door windows to be fully opened by momentarily pulling the appropriate window switch lever to the second detente and then releasing.

The driver door switch assembly (DDSA) is wired to the DDM for power, ground, and serial data communications. It has no other external circuits concerned with power window operation. The DDSA internally supplies the voltage and ground to the contacts of the integral power window switches. When one of the window switches is operated, the contacts for that switch are closed to ground and the DDSA recognizes the flow of voltage as a specific window switch signal input. The DDSA reports the switch activity to the DDM.

Both the driver and front passenger door windows can be operated in the express down mode from the DDSA. These switches are constructed in a way that allows the contacts of both signal circuits to indicate the express down command. When either window switch lever is pulled to the second detente of the down position, first the down signal contacts are closed, then the up signal contacts are closed. The DDSA interprets this two contact signal as an express down request.

The front passenger door module supplies battery voltage to the two signal circuits, and a ground to the ground circuit, of the front passenger door window switch. One of the signal circuits is for an Up signal, the other is for a Down signal. When the window switch is operated, the normally open contacts for that function are closed to ground, battery voltage flows through the circuit and the switch, providing the front passenger door module with the neccessary signal input.

The front passenger door window can be operated in the express down mode from the front passenger door window switch. The switch is constructed in a way that allows the contacts of the two signal circuits to indicate the express down command. When the window switch lever is pulled to the second detente of the down position, first the down signal contacts are closed, then the up signal contacts are closed. The front passenger door module interprets this two contact signal as an express down request.

Each rear door module supplies battery voltage to the two signal circuits of its associated window switch. One signal circuit is for an Up signal, the other is for a Down signal. Each rear door module also supplies a ground circuit to its associated window switch. When the window switch is operated, the normally open contacts for that function are closed to ground, battery voltage flows through the circuits and the switch, providing the associated door module with the neccessary signal.

In order to control power window operations, as well as other door functions, door modules must be powered up. Battery voltage is supplied from the rear fuse block, through separate circuits, to each door module. Each door module is separately grounded through a ground stake. The door modules also use these voltage and ground supplies to provide power and ground to their associated window and lock switches. In addition, the front door modules use these voltage and ground supplies for outside rearview mirror operations.

The DDM battery voltage circuit is fed by the DRVMDL 10 amp fuse in the Rear Fuse Block.

The PDM battery voltage circuit is fed by the PASS MDL 10 amp fuse in the Rear Fuse Block.

The LRDM battery voltage circuit and the RRDM battery voltage circuit are both fed by the RRDR MDL 10 amp fuse in the Rear Fuse Block.

These circuits are in the C1 harness connector of each door module and must not be confused with the door modules voltage and ground circuits that are used exclusively to drive the power window motors.

Each door module has its own separate battery positive voltage supply circuit, used exclusively for power window motor operation. Although these circuits are separate, they are all fed by the same PWR WDO 30 amp circuit breaker located in the rear fuse block. Each door module also has a separate ground circuit used exclusively for power window motor operation. When a door module drives a power window motor, the door module internally connects these voltage and ground circuits to the appropriate window motor control circuits. The battery voltage and ground circuits designated for window motor operation are in the C3 harness connector of each front door module, and in the C2 harness connector of each rear door module, and must not be confused with the battery voltage and ground circuits of the C1 harness connectors.

Each door module applies battery voltage and ground, through the window motor control circuits, to its associated window motor. The window motors are reversible. The direction the window moves depends on which motor control circuit the battery voltage is applied to, and which motor control circuit the ground is applied to. To move the window in the Up direction, the module applies battery voltage to the window motor up control circuit, and ground to the window motor down control circuit. When a window Down movement is requested, the module reverses the polarity, applying battery voltage to the window motor down control circuit and ground to the window motor up control circuit.

The window lockout switch is built into the Driver Door Switch Assembly (DDSA). When the lockout switch button is momentarily pressed, the normally open contacts of the lockout switch are closed to ground, the LED indicator is illuminated, and the DDSA interprets the switch signal. The DDSA then sends a message, via the power door serial data line, to the driver door module (DDM) indicating that the switch is active. The DDM then sends a message, via the power door serial data line to, either both rear door modules, or, to all of the passenger door modules, prohibiting the passenger windows from being operated from their locally mounted window switches.The passenger door windows can still be operated by using the appropriate window switch built into the DDSA.