High-Speed Windshield Wipers

When the multi-function switch is set to the high-speed position, it supplies ground to the high/low speed relay coil and the run/park relay coil, which causes the windshield wiper motor to operate at high speed. During high-speed operation only, both the high/low-speed relay coil ground and the run/park relay coil ground are controlled directly by the multi-function switch. This differs from LOW speed or intermittent operation when the run/park relay coil is controlled by the microprocessor. When the switch is placed in the OFF position, the motor continues to operate until the motor returns to the PARK position and the internal Hall-effect sensor senses the motor magnet. The output to the run/park relay deactivates the relay and disconnects the voltage to the motor.

Since the high/low relay coil and the run/park relay coil are both is controlled by a hard wired circuit to the multi-function switch, the windshield wipers will still operate in high-speed mode if the internal windshield wiper module fails, but will not automatically park when the multi-function switch is turned to the OFF position.