See also:

Using KEYLESS-GO to start the engine
WARNING As long as the SmartKey is in your vehicle, the vehicle can be started. Therefore, never leave children unattended in the vehicle, as they could otherwise accidentally start the eng ...

Mercedes-Benz M-Class Owners Manual
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Changing the settings of the locking system
You can change the setting of the locking system in such a way that only the driver's door and the fuel filler flap are unlocked. This is useful if you frequently travel on your own. - To chang ...