See also:

Cleaning the trailer tow hitch
The ball coupling must be cleaned if it becomes dirty or corroded. – Remove rust on the ball of the ball coupling, e.g. with a wire brush. – Remove dirt with a clean, lint-free cloth or a brus ...

Important safety notes
WARNING For safety reasons, switch off the windshield wipers and remove the key from the ignition lock before changing the wiper blades (vehicles with KEYLESS-GO: make sure that the on-board ...

General notes
If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged. - Check the battery in ...