Mercedes-Benz M-Class Owners Manual

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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. ...

Removing the towing eye
Loosen the towing eye and unscrew it. Attach cover 1 to the bumper and press until it engages. Place the towing eye in the vehicle tool kit. ...

Charging the battery
WARNING Never charge a battery still installed in the vehicle unless a battery charger unit approved by Mercedes-Benz is being used. Gases may escape during charging and cause explosions ...