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Circuit Operation

A permanent magnet (PM) motor operates each of the power windows. Each motor raises or lowers the glass when voltage is supplied to it. The direction the motor turns depends on the polarity of the supply voltage. The switches control the supply voltage's polarity.

The master switch assembly on driver's side controls all of the motors. Passenger's side power window switch controls only the motor at its location.

Each motor is protected by a built in electronic circuit breaker PTC. If a power window switch is held too long with the window obstructed or after the window is fully up or down, the PTC resistance increases and the circuit breaker removes voltage from the motor. The circuit breaker will reset after the resistance returns to normal and the circuit cools down.