Rain Sensor: Description and Operation

The outside moisture sensor monitors moisture accumulation on the windshield and uses a windshield wiper/washer switch status input to provide wipe commands to the windshield wiper motor module. The windshield wiper/washer switch delay positions are used to activate the automatic operating mode and to adjust the level of sensitivity to moisture accumulation when commanding a wiper motor wipe cycle. The windshield wiper/washer switch is an input to the windshield wiper motor module. The windshield wiper motor module sends the windshield wiper/washer switch status to the moisture sensor using a PWM voltage signal through the moisture sensor signal 1 circuit. The moisture sensor sends a PWM voltage signal to the wiper motor module through the moisture sensor signal 2 circuit whenever the ignition is in the accessory or run positions. The moisture sensor uses the moisture sensor signal 2 circuit to command wiper motor wipe cycles and to confirm the moisture sensor signal 1 is being received. If at anytime communication between the moisture sensor and wiper motor module is lost, the wiper motor module will use the inputs from the windshield wiper/washer switch in the delay positions to operate the wiper motor at continuous variable delay intervals.