See also:

Mercedes-Benz M-Class Owners Manual
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Through-loading facility in the rear compartment
WARNING Do not transport any unsecured items in the through-loading area. The through-loading facility is opened from the cargo compartment. – Unlatch the rear seat backrests and tilt th ...

Vehicle remote closing
If you forget to lock your vehicle but are no longer in the vicinity of the vehicle, it can be locked for you by the Mercedes-Benz Customer Assistance Center. The vehicle can be locked remotely ...