Washer Operation
WARNING: This page is about a different car, the 2008 Buick LaCrosse and 2008 Buick Allure. However, it is still accessible from the selected car via links, so may be relevant.
In the WASH position the windshield wiper/washer switch supplies a ground signal to the body control module (BCM) through the windshield washer switch signal circuit. The BCM will energize the WIPER relay that operates the windshield wiper motor at low speed and the BCM then applies voltage to the windshield washer fluid pump. The washer pump will function for as long as the washer switch is applied. The wiper motor will continue to operate for approximately 2 wipe cycles after the wash switch is released.