Theory Of Operation
WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
The Body Control Module (BCM) receives the rear wiper request as network message on the communications network. The BCM energizes the coil on the Rear Wiper Relay, which is grounded through the Power Distribution Center ground.