Wiper and Washer Systems: Description and Operation

When the headlight switch is in PARK or HEAD, voltage is applied through the RED/BLK wire to the dimming circuit in the A/T gear position indicator. The illumination intensity is varied by the dash lights brightness controller through the RED return wire.

A/T Gear Position Indicator
When the ignition switch is in ON (II) or START (III), battery voltage is applied to the combination wiper switch, and the windshield wiper motor.

Low Speed
When you turn the wiper switch to LO, the wiper motor's low speed winding is grounded. The path to ground is completed through the BLU wire and the LO speed contacts of the wiper switch at G401, and the wipers run at low speed.

Park/OFF
When you turn the wiper switch OFF, the integrated control unit (PARK input) grounds the wiper motor through the BLU/WHT wire. The cam switch on the motor signals the integrated control unit that the wipers are in the PARK position; the control unit then removes ground from the motor, and the wipers stop in the PARK position.

High Speed
When the wiper switch is in HI, the high speed windings of the windshield wiper motor are grounded. The path to ground is completed through the BLU/YEL wire and the HI contacts of the wiper switch at G401, and the wipers run at high speed.

Intermittent
When the wiper switch is in INT, battery voltage is applied through the YEL/BLU wire to the integrated control unit (Intermittent wiper ON input). The integrated control unit (Intermittent/Park Wiper Control) grounds the low speed windings of the wiper motor and the wipers make a single sweep every few seconds (See Low Speed Operation). When the wiper returns to the PARK position, the park switch applies battery voltage through the BLU/WHT wire to the integrated control unit (PARK input), and the wipers stop in the PARK position.

Mist
When you pull the wiper switch down to the MIST position, the high speed windings of the wiper motor are grounded. The path to ground is completed through the BLU/YEL wire and the closed contacts of the mist switch at G401, and the wipers make one pass across the windshield.

Washer
When you pull the wiper switch toward you to turn ON the washer switch, battery voltage is applied to the washer motor. The motor then pumps fluid onto the windshield until you release the lever. On models with combined wiper/washer operation (Canada), the integrated control unit (windshield washer ON input) senses power at the BLK/GRN wire terminal and runs the washer motor whenever the wipers run.