Circuit Description
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
The body control module (BCM) monitors the windshield wiper switch low signal circuit. When the wiper switch is placed in a low position, a signal is applied to the BCM through the windshield wiper switch low signal circuit. The BCM then applies a battery positive voltage to the WPR1 relay control circuit which energizes the WPR1 relay, allowing the battery positive voltage from FTR WPR fuse through the switched side of the WPR1 relay to the windshield wiper motor.