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 unti ...

Mercedes-Benz M-Class Owners Manual
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Using KEYLESS-GO
The KEYLESS-GO key must be outside the vehicle. All the doors must be closed. •► Touch recessed sensor surface 1 on the door handle until the side windows and the sliding sunroof or the ...