Circuit Description

How the Circuit Works

CAUTION: Disconnect the window switch connector before you start. You could unintentionally switch the window to "automatic down" while working in the driver's or front passenger's door with the power on. The moving glass could injure your arms, hands, or fingers.

The power windows system is a multiplex controlled system. The power window master switch and the front passenger's, left rear, and right rear power window switches are the main operation controls of the power windows system. Both the power window master switch and the front passenger's power window switch contain a control block.

Reversible electric motors drive the power windows. Each motor is protected by a non-serviceable built-in circuit breaker. The circuit breaker will reset automatically as it cools.

Power Supply
Battery voltage is supplied at all times to the power window relay and through fuses 26 and 30 to the power window master switch and the front passenger's power window switch, respect lively. With the ignition switch in ON (II), battery voltage is supplied through fuse 1 to the power window master switch enabling power window operation.

When the main switch is ON, the power window master switch provides ground for the coil of the power window relay, energizing it. When energized, the power window relay supplies battery voltage through fuse 33 to the left rear power window switch and through fuse 32 to the right rear power window switch, illuminating their LED's. All fuses are located in the under-dash fuse/relay box.

Driver's Window
When the driver's power window switch of the power window master switch is pushed to DOWN or pulled to UP, the signal for down or up is input to the control block. The control block provides power and ground to the driver's power window motor, lowering or raising the window until the switch is released.

When the driver's power window switch is pushed to AUTO DOWN or pulled to AUTO UP, the signal for auto down or auto up is inputted to the control block. The control block provides power and ground to the driver's power window motor, lowering or raising the window. As the window descends or ascends, the pulser in the driver's power window motor sends pulsing signals to the control block. When the window reaches the fully down or fully up position, the pulsing signal stops and the control block removes power and ground from the driver's power window motor. If something obstructs the window during the AUTO UP operation, the control block will detect no pulses from the pulser. For safety reasons, the control block will make the driver's power window motor stop immediately and reverse.

All Passenger Windows
All windows can be opened and closed by the power window master switch. The rear windows are disabled when the main switch is OFF. The driver's and front passenger's power window motors remain operable when the main switch is OFF.

Front Passenger's Window
When the front passenger's switch of the front passenger's power window switch is pushed to DOWN or pulled to UP, the signal for down or up is inputted to the control block. The control block provides power and ground to the front passenger's power window motor lowering or raising the window until the switch is released.

When the front passenger's switch is pushed to AUTO DOWN or pulled to AUTO UP, the signal for auto down or auto up is inputted to the control block. The control block provides power and ground to the front passenger's power window motor, lowering or raising the window. As the window descends or ascends, the pulser in the front passenger's power window motor sends pulsing signals to the control block. When the window reaches the fully down or fully up position, the pulsing signal stops and the control block removes power and ground from the front passenger's power window motor. If something obstructs the window during the AUTO UP operation, the control block will detect no pulses from the pulser. For safety reasons, the control block will make the front passenger's power window motor stop immediately and reverse.

When the front passenger's window is opened or closed from the power window master switch, the control block communicates that command via a UART signal to the front passenger's power window switch.

Left Rear Window
When the left rear power window switch is pushed to DOWN, power is supplied to the coil of the left rear power window switch down relay, energizing it. Battery voltage is supplied to the left rear power window motor through the energized relay. A path to ground for the motor is provided by the left rear power window switch up relay, lowering the window until the switch is released or the window is fully lowered.

When the left rear power window switch is pulled to UP, power is supplied to the coil of the left rear power window switch up relay, energizing it. Battery voltage is supplied to the left rear power window motor through the energized relay. A path to ground for the motor is provided by the left rear power window switch down relay, raising the window until the switch is released or the window is fully lowered.

When the left rear window is opened or closed from the power window master switch, the control block sends signals to the relays within the left rear power window switch.

Right Rear Window
When the right rear power window switch is pushed to DOWN, power is supplied to the coil of the right rear power window switch down relay, energizing it. Battery voltage is supplied to the right rear power window motor through the energized relay. A path to ground for the motor is provided by the right rear power window switch up relay, lowering the window until the switch is released or the window is fully lowered.

When the right rear power window switch is pulled to UP, power is supplied to the coil of the right rear power window switch up relay, energizing it. Battery voltage is supplied to the right rear power window motor through the energized relay. A path to ground for the motor is provided by the right rear power window switch down relay, raising the window until the switch is released or the window is fully lowered.

When the right rear window is opened or closed from the power window master switch, the control block sends signals to the relays within the right rear power window switch.