How the Circuit Works

POWER WINDOWS

How the Circuit Works

CAUTION: You could injure your arms, hands, or fingers if you unintentionally switch the driver's window to "automatic down" or "automatic up" while working in that door with the power on. Disconnect the window switch connector or the battery when working in the driver's door.

System Description

The operation of the power windows is controlled by the main switch in the power window master switch. When the main switch is in OFF, only the driver's door window can be opened or closed. With the main switch ON, all windows can be opened or closed either by switches in the master panel, or switches in the doors. The driver's window switch also has an automatic down or up mode which is operated by firmly moving the switch down or up.

The power windows are driven by reversible motors. Each motor is protected by a built-in circuit breaker. If the window switch is held on too long (with the window obstructed, or after the window is fully up or down), the circuit breaker opens the circuit. The circuit breaker resets automatically as it cools.

Driver's Window

With the ignition switch in ON or START, voltage is provided to the coil of the power window relay through fuse 6. The contacts of the power window relay close, and voltage is applied to the power window master switch. When you push the power window master switch to UP, voltage is applied to the driver's power window motor. The driver's power window motor then drives the window up. When you push the switch to DOWN, voltage is applied in the opposite direction and the motor drives the window down.

Auto Down

With the ignition switch in ON or START, voltage is applied to the coil of the power window relay. The contacts of the power window relay close and voltage is applied to the power window master switch. When you firmly move the driver's switch down, voltage is applied through the driver's switch to the driver's window motor. The control unit receives pulses at the pulser input while the motor is running. When the window is fully down, the motor stops, and pulses are no longer generated by the pulser. This is sensed by the control unit at the pulser input, and voltage is no longer applied to the driver's window motor.

Auto Up

With the ignition switch in ON or START, voltage is applied to the coil of the power window relay. The contacts of the power window relay close and voltage is applied to the power window master switch. When you firmly move the driver's switch up, voltage is applied through the driver's switch to the driver's window motor. The control unit receives pulses at the pulser input while the motor is running. When the window is fully up, the motor stops, and pulses are no longer generated by the pulser. This is sensed by the control unit at the pulser input, and voltage is no longer applied to the driver's window motor.

Passenger Window

With the ignition switch in ON or START, voltage is applied to the coil of the power window relay through fuse 6. The contacts of the power window relay then close, applying voltage to the passenger's power window switch and the power window master switch. With the master panel main switch ON, the passenger window can be operated from the individual window switch or from the master panel switch.

When you push the passenger's window switch to UP, voltage is applied to the passenger's window motor. (The motor is grounded through the contacts in the front passenger's window switch and the power window master switch.) The window moves up as long as you hold the switch in the UP position. If you push the switch to DOWN, voltage is applied in the opposite direction to the front passenger's window motor, and the window moves down as long as you hold the switch in the DOWN position.

When you push the passenger's switch in the master panel to UP, voltage is applied through the passenger's window switch contacts to the passenger's window motor. (The motor is grounded through the contacts in the passenger's window switch and the power window master switch.) The window moves up as long as you hold the switch in the UP position. If you push the switch to DOWN, voltage is applied in the opposite direction to the passenger's window motor, and the window moves down as long as you hold the switch in the DOWN position.