Pneumatic Wiper Motor Control Valves
The wiper motor control valves switch the wiper motor on or off, control the wiper motor speed, and park the motor. Turning the knob clockwise from the OFF position starts the wiper. The wiper speed is continuously variable, increased by turning the knob clockwise. Turning the knob counterclockwise decreases wiper speed. Turning past the detent turns the wiper off. Turning counterclockwise past the off position against the momentary spring pressure parks the wiper.