Rear Wiper/Washer System

REAR WIPER/WASHER SYSTEM DESCRIPTION AND OPERATION

REAR WIPER/WASHER SYSTEM COMPONENTS
The rear window wiper/washer system consists of the following components:
- Rear window wiper/washer switch
- Rear window wiper module
- Washer fluid pump - reversible
- Washer fluid pump relay
- RR WPR 5A fuse - Fuse Block IP
- RR WPR 25A fuse - Fuse Block Underhood
- W/S WASH 15A fuse

REAR WIPER/WASHER SYSTEM OPERATION
The rear window wiper motor module is part of the rear window wiper module and controls wiper motor operation. Battery voltage supplied to the wiper motor assembly is used to operate the wiper motor in all modes and to return the rear wiper arm to the park position after the ignition is turned OFF. Accessory voltage supplied to the rear window wiper/washer switch is used to supply the rear window wiper/washer switch signal and control circuits. In switch positions low and high the wiper switch signal circuit voltage level to the wiper motor module determines the wiper motor delay interval. The rear window washer switch signal circuit activates the rear window wiper motor wash operating mode, and the same signal is used to signal the windshield wiper motor module the rear window wash mode is active. The washer fluid pump is a reversible motor and is used to wash both the windshield and rear window. The washer fluid pump is controlled by the windshield wiper motor module through the washer fluid pump relay. The washer fluid pump relay coil and switch are supplied battery positive voltage, and during the windshield or rear window wash modes the wiper motor module grounds the washer fluid pump relay control circuit energizing the relay. When the relay is energized battery positive voltage to the switch side of the relay is supplied to the windshield wiper motor module through the washer fluid pump supply voltage circuit. The windshield wiper motor module also controls the voltage polarity of the washer fluid pump control circuits. During rear window wash operation the rear window washer pump control circuit supplies positive voltage to the washer fluid pump and the windshield washer pump control circuit is the ground circuit.

LIFTGATE AJAR SWITCH SIGNAL TO REAR WINDOW WIPER MODULE
The liftgate ajar switch signal enable/disable the rear wipers operation. The liftgate ajar switch signal is supplied voltage through a resistor, then monitored within the rear window wiper module. When the liftgate is closed, the ajar switches are opened so the rear window wiper module detects voltage on the liftgate ajar switch signal. In this case the rear wipers can work. If the liftgate is opened the liftgate ajar switches close and provide ground to liftgate ajar switch signal. The rear window wiper module detects this and disables the rear wipers.