GM Service Manual Online
For 1990-2009 cars only

Windshield Wiper/Washer System Components

The windshield wiper/washer system consists of the following components:

    • Windshield wiper/washer switch
    • Windshield wiper motor
    • Windshield washer pump
    • Windshield washer relay
    • FRT WIPER 25A fuse
    • W/S WASH 15A fuse

Wiper/Washer System Operation

The windshield wiper motor module is part of the windshield wiper motor cover and controls the windshield wiper motor and washer pump operation. The windshield wiper motor is a 2 speed motor and is operated at low speed in all modes except HIGH. The accessory voltage supply circuit to the windshield wiper motor provides the power for operating the wiper motor and the wiper motor module. The windshield wiper switch supply voltage circuit is a 12-volt reference from the wiper motor module to the wiper/washer switch. The WASH, MIST, LOW, and DELAY modes are controlled by the windshield wiper/washer switch through a series of internal resistors, and the switch position determines the point on the resistor assembly where the reference voltage is applied. The windshield wiper switch signal 1 circuit supplies the signal voltage from the switch assembly to the wiper motor module which determines the operating mode. Windshield wiper motor high speed operation is controlled by the windshield wiper/washer switch through the windshield wiper switch high signal circuit. The windshield wiper switch high signal circuit is supplied 12 volts by the wiper motor module and when the wiper/washer switch is turned to the HIGH position the windshield wiper switch high signal circuit is grounded. The windshield washer pump is controlled by the wiper motor module through the windshield washer relay. The windshield washer relay coil and switch is supplied battery positive voltage, and during WASH mode the wiper motor module grounds the washer relay control circuit energizing the relay. While the relay coil is energized battery positive voltage to the switch side of the relay is supplied to the washer pump control circuit.