Wiper and Washer Systems: Description and Operation

How the Circuit Works

With the ignition switch in ON (II) or START (III), battery voltage is applied to the windshield wiper motor, wiper high relay coil, wiper low relay coil, and the wiper INTERMITTENT relay coil.

Low Speed

When you turn the windshield wiper/washer switch to LOW, the wiper INTERMITTENT relay is energized, grounding the low speed winding of the motor through the BLU/RED wire, wiper low relay, BLU/YEL wire, wiper INTERMITTENT relay, and BLK wire to G202. The wipers then run at low speed.

High Speed

When you turn the windshield wiper/washer switch to HIGH, the wiper low and high relays are energized. This grounds the high speed winding of the motor through the BLU/GRN wire, wiper high relay, and BLK wire to G202. The wipers then run at high speed.

Park and Off

When you turn the windshield wiper/washer switch to OFF, all the relays are de-energized. The low speed winding of the motor is grounded through the BLU/RED wire, wiper low relay, BLU/YEL wire, wiper intermittent relay, BLU/WHT wire and the park switch in the RUN position. The wipers then run at low speed until they reach the PARK position. With the park switch in the PARK position, battery voltage is supplied to both sides of the wiper motor low speed winding, and the motor stops.

Intermittent

When you turn the windshield wiper/washer switch to INT, battery voltage is supplied through fuse 6 to the integrated control unit INT input. The INT output grounds the low speed winding of the windshield wiper motor, and the wipers make one pass at low speed (see low speed operation). When the wipers return to the PARK position, the park switch applies battery voltage to the integrated control unit PARK input through the BLU/WHT wire. This tells the integrated control unit that the wipers have parked. The control unit uses this information to start the delay timer. The delay is dependent upon the delay control selected on the windshield wiper/washer switch. The cycle repeats until you select another switch position.

Mist

When you push the windshield wiper/washer switch down to MIST and release it, the high speed winding of the wiper motor is grounded (see high speed operation) through the MIST contact of the windshield wiper/washer switch to G401. The wipers then make one pass in high speed and return to the PARK position.

Washer

When you pull the wiper switch lever toward you to engage the washer function, battery voltage is applied to the washer motor relay and the wash input of the integrated control unit through the YEL/GRN wire. The washer motor relay energizes and supplies battery voltage to the windshield washer motor. The integrated control unit grounds the windshield wiper motor low speed winding (see Low Speed and Intermittent operation on this page). The windshield washer motor then runs for as long as you hold the washer switch lever back. Once you release the lever, the wipers will make several passes before stopping in PARK.