See also:

Centrally locking and unlocking thevehicle from the inside
You can centrally lock or unlock the vehicle from the inside. The central locking/unlocking button does not lock or unlock the fuel filler flap. The buttons are located on both front doors. ...

Remote vehicle locking
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 ...

Important safety notes
WARNING Do not park this vehicle in areas where combustible materials can come into contact with the hot exhaust system. Do not park the vehicle on dry grassland or harvested grain fields. ...