When the rear wiper switch is activated the Steering Wheel Module (SWM) sends a LS CAN message to activate the rear wipers to the Underhood Electrical Center (UEC). The UEC Sends a request to the Rear Electrical Center (REC) to activate the rear wipers. the rear wipers are shut off by pulling the wiper switch in the other direction.

When the SWM sends a message to activate the rear washer, the UEC activates the rear washer pump. The REC activates the rear wiper when the LS CAN message from the UEC has been recieved. Below a certain speed, the wiper is activated a bit later. If the washer fluid is too low, the rear washer pump is deactivated.