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For 1990-2009 cars only

Wiper/Washer System Components

The Wiper/Washer System consists of the following components:

    • Windshield wiper / washer switch
    • Windshield wiper system module / motor
    • Windshield washer fluid pump
    • Windshield washer fluid level switch
    • Outside moisture sensor
    • Body Control Module (BCM)
    • Instrument Panel Cluster (IPC)
    • WSW 30A fuse
    • WSW/RFA 10 fuse

Wiper / Washer System Description

The windshield wiper motor module is part of the windshield wiper motor cover and controls the wiper motor operation. The windshield wiper motor is a 2 speed motor. Windshield wiper DELAY operation is a low speed wiper motor function with a variable delay interval between the wipe cycles. The DELAY interval is controlled through a series of resistors within the wiper / washer switch.

Wiper / Washer System Operation

Voltage is supplied by the:

    • WSW/RFA fuse to the windshield wiper / washer switch and to the outside moisture sensor
    • WSW fuse to the windshield system module / motor

Ground is applied from:

    • G106 to the windshield wiper system module
    • G202 to the windshield washer fluid level switch and the windshield washer fluid pump
    • G400 to the outside moisture sensor

Low Speed Operation

When the wiper / washer switch is in the LOW position, two different voltages are applied to the windshield wiper module to operate the windshield wiper motor at low speed.

    • Reduced voltage is supplied through a resistor within the switch to the windshield wiper signal 2 circuit.
    • Full voltage is applied to the windshield wiper signal 1 circuit.

High Speed Operation

With the wiper / washer switch in the HIGH position, three different voltages are applied to the windshield wiper module to operate the windshield wiper motor at high speed.

    • Reduced voltage is supplied through a resistor within the switch to the windshield wiper signal 2 circuit.
    • Full voltage is applied to the windshield wiper signal 1 circuit.
    • Full voltage is applied to the windshield wiper signal high speed circuit.

Intermittent Operation

Windshield wiper intermittent operation is a low speed wiper motor function with a variable delay interval between the wiper motor cycles. The delay interval is determined by a series of resistors within the wiper/washer switch. During intermittent wiper operation, the windshield wiper switch signal 1 circuit is reduced through the resistors.

When the wiper / washer switch is in the DELAY position, two different voltages are applied to the windshield wiper module to operate the windshield wiper motor in an intermittent mode at low speed.

    • Reduced voltage is supplied through a resistor within the switch to the windshield wiper signal 2 circuit.
    • Variable reduced voltage, dependant upon windshield wiper switch position, is applied to the windshield wiper signal 1 circuit.

Park Position Operation

When the windshield wiper / washer switch is turned to the OFF position while the wiper motor is somewhere in mid-cycle, the wiper motor module will continue to operate the wiper motor until the wipers reach the park position. If the ignition is turned off while the wipers are in mid-cycle, the wipers will stop immediately where they are. The wipers will park the next time the ignition is cycled to the ON position.

Mist Operation

When the wiper switch is moved to the MIST position, the wiper motor will operate in the low speed mode until the switch is released. Two different voltages are applied to the windshield wiper module to operate the windshield wiper motor until the cycle is completed.

    • Reduced voltage is supplied through a resistor within the switch to the windshield wiper signal 2 circuit.
    • Full voltage is applied to the windshield wiper signal 1 circuit.

Washer Operation

When the wiper switch is moved to the WASH position, the washer fluid pump and wiper motor will operate until the switch is released. When the wiper switch is moved to the WASH position, full voltage is applied to the windshield wiper signal 2 circuit to the windshield wiper motor. The wiper module / motor then applies full voltage to the washer fluid pump through the washer pump motor control circuit. The wiper motor will continue to operate for approximately 2 wipe cycles after the wash switch is released. Ground for the windshield washer fluid pump is supplied from G106.

Check Washer Fluid Message Operation

The low washer fluid indicator is located in the instrument panel cluster (IPC). Ground is applied at all times from G202 to the windshield washer fluid level switch. When the washer fluid is low, ground is applied to the washer fluid level switch circuit to the body control module (BCM). The BCM then communicates through the class 2 data circuits to the IPC. The IPC will then illuminate the "check washer fluid message" in the driver information center (DIC).

Outside Moisture Sensor Operation (Optional With CE1)

The outside moisture sensor monitors moisture accumulation on the windshield and commands the windshield wiper module / motor. The windshield wiper / washer switch intermittent positions are used to activate the automatic operating mode and to adjust the level of sensitivity to moisture accumulation. The windshield wiper module / motor sends the status of the windshield wiper / washer switch to the moisture sensor using a PWM voltage signal through the moisture sensor signal 1 circuit. Moisture sensor signal 2 confirms that the moisture sensor is receiving the moisture sensor signal 1. If communication is lost, the wiper module / motor will use the inputs from the windshield wiper / washer switch in the intermittent positions to operate the wiper module / motor at delay intervals.