See also:

Changing the battery
You require a CR 2025 3 V cell battery. Take the mechanical key out of the SmartKey. Press mechanical key 2 into the opening in the SmartKey in the direction of the arrow until battery t ...

Mercedes-Benz M-Class Owners Manual
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Trailer load/noseweight
The trailer load/noseweight affects the gross weight of the vehicle. If a trailer is attached, the trailer load/noseweight is included in the load along with occupants and luggage. The trailer ...