See also:

Problems with the SmartKey
Problem Possible causes/consequences and  Solutions You cannot lock or unlock the vehicle using the SmartKey. The SmartKey battery is discharged or nearly discharged ...

Service messages
Information on the type of service and service intervals (see separate Service Booklet). You can obtain further information from an authorized Mercedes-Benz Center or at http://www.mbusa.com (USA ...

Cleaning the headliner and carpets
Roof lining: use soft brushes or dry shampoo if it is particularly dirty. Carpets: use carpet and textile cleaners that have been approved and recommended by Mercedes-Benz. ...