See also:

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 lockin ...

Additives
Do not use any additives in the engine oil. This could damage the engine. ...

Problems with your vehicle
If you should experience a problem with your vehicle, particularly one that you believe may affect its safe operation, we urge you to contact an authorized Mercedes-Benz Center immediately to have ...