See also:

Mercedes-Benz M-Class Owners Manual
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Using the SmartKey
The SmartKey must be close to the driver's door handle. Point the tip of the SmartKey at the driver's door handle. Press and hold the button until the side windows and the panoram ...

Activating the HOLD function
Make sure that the activation conditions are met. Depress the brake pedal. Quickly depress the brake pedal further until HOLD display 1 appears in the multifunction display. The HOLD ...