Using the rain sensor's memory function
The rain sensor monitors the amount of water on the windshield and automatically starts the windshield wipers.
Activating/deactivating memory function
The rain sensor's memory function can be set to activate so that the rain sensor button does not need to be pressed each time the engine is started:
Tap 
in the center display.
in the center display.Then tap More.
Select Mirrors and wipers and activate/deactivate the rain sensor's memory function.