Low and Intermittent Operation (Front Wipers)

During Low and Intermittent operation, the windshield wiper washer switch provides a resistor ladder to determine the amount of wiper delay requested. The wiper delay is determined by the BCM based on the input from the wiper washer switch. In the Low and Intermittent position, the windshield wiper washer switch supplies a ground signal to the windshield wiper switch low signal circuit indicating to the BCM that intermittent or low speed wiper operation is request. The resistor ladder determines the voltage signal seen at the BCM, with various voltage levels equaling different delay speeds. Upon this signal, the BCM will apply B+ to the WIPER PCB relay coil. The relay coil will become energized, creating a magnetic field and closing the relay switch. B+ will be applied to the windshield wiper motor low control circuit. During low speed operation, the BCM will supply B+ to relay continuously, operating the wipers at a steady low speed. During intermittent operation, the BCM will selectively supply B+, providing the intermittent delay.