See also:

Mercedes-Benz M-Class Owners Manual
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Headlamps fogged up on the inside
The headlamps may fog up on the inside if there is high atmospheric humidity. •► Drive with the headlamps switched on. The level of moisture diminishes, depending on the length of the jour ...

Setting a speed
WARNING Keep in mind that it may take a brief moment until the vehicle has made the necessary adjustments. Increase or decrease the set vehicle speed to a value that the prevailing road c ...