Windshield Wiper/Washer System Description and Operation

The windshield wiper/washer switch supplies voltage on the signal circuit or the control circuit of the windshield washer pump to the BCM for windshield wiper/washer operation. When WASH, MIST, DELAY, LOW, or HIGH is detected, the BCM energizes the Wiper 1 relay by suppling voltage to the relay coil. This allows battery voltage from the WIPER fuse to flow through the relay switched input then through the contacts and out the relay switched output to the WIPER 2 relay switch contacts. Since the WIPER 2 relay switch contacts are normally closed to the low speed circuit of the windshield wiper motor, the motor will operate at low speed.