See also:

Important safety notes
WARNING Do not turn off the engine before the vehicle has come to a complete stop. With the engine not running, there is no power assistance for the brake and steering systems. In this case, ...

De-registering (de-authorizing) a mobile phone
Mercedes-Benz USA, LLC recommends deauthorizating in both COMAND and the mobile phone. Subsequent authorization may otherwise fail. To call up the telephone menu: press the function button ...

Locking the vehicle (mechanical key)
If the vehicle can no longer be locked with the SmartKey, use the mechanical key. Open the driver's door. Close the front-passenger door, the rear doors and the tailgate. Press the locki ...