Wiper and Washer Systems: Description and Operation

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

Low Speed
When you rotate the front wiper switch to LO, the intermittent relay is energized and the low speed winding of the motor is grounded through the BLU/RED wire, low relay, BLU/YEL wire, intermittent relay, and BLK wire to G404. The wipers then run at low speed.

High Speed
When you rotate the front wiper switch to HI, the windshield wiper low and high relays are energized. The high speed winding of the motor is grounded through the BLU/YEL wire, high relay, and BLK wire to G404. The wipers then run at high speed.

Park and Off
When you move the front 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, low relay, BLU/YEL wire, intermittent relay, 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 move the wiper switch to INT battery voltage is applied through fuse 6 to the integrated control unit. The integrated control unit grounds the coil of the intermittent wiper relay. The relay, in turn, provides ground to the low speed windings of the wiper motor, and the wipers make a single sweep 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 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 wiper switch. The cycle repeats until you select another switch position.

Mist
When you push the wiper/washer lever down and hold it, the high speed winding of the front wiper motor is grounded through the MIST contact in the wiper/washer switch. The wipers sweep at high speed until you release the lever. The PARK/OFF function then takes over and the wipers stop in the PARK position.

Washer
When you pull the wiper/washer lever toward you, battery voltage is applied to the front washer motor and the integrated control unit. The integrated control unit grounds the coil of the intermittent relay. The relay, in turn, provides ground to the low speed windings of the wiper motor. The washer motor pumps washer fluid onto the windshield and the wipers run at low speed until you release the lever; the wipers then make one more sweep.