See also:

Mercedes-Benz M-Class Owners Manual
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Resetting to factory settings
For safety reasons, the Day Lights function in the Lights submenu is only reset when the vehicle is stationary. Press the or button on the steering wheel to select the Settings menu. P ...

Driving on sand
WARNING   Do not reduce the tire inflation pressure before driving through sand. However, if you do so, remember to correct the tire inflation pressure before continuing your trip. Drivi ...