See also:

Active light function
The active light function is a system that moves the headlamps according to the steering movements of the front wheels. In this way, relevant areas remain illuminated while driving. This allows ...

Mercedes-Benz M-Class Owners Manual
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Trailer towing
PARKTRONIC is deactivated for the rear area when you establish an electrical connection between your vehicle and a trailer. Fold in the ball coupling if the trailer tow hitch is not requir ...