Circuit Operation

The power windows are driven by reversible permanent magnet motors. Each motor is controlled by two normally closed and grounded switches. When the right window switch is in the UP position, CKT 166 is connected to battery voltage and the motor runs to drive the window up. When the switch is released, the contacts return to their normal position and CKT 166 is returned to ground. The motor stops.See Figure .

To lower the window, the switch connects CKT 166 to battery voltage. The polarity across the motor is reversed from the polarity that occurs when the UP switch is pressed. The motor runs the opposite way to drive the window down. The left window circuit operates in a similar manner.

Each motor is protected by a built-in solid state circuit breaker. If a window switch is held on too long with the window obstructed or after the window is fully up or down, the circuit breaker opens, breaking continuity with the power window motor. After the circuit cools down, the circuit breaker resets automatically.