See also:

General notes
If you cannot lock or unlock the vehicle with the SmartKey, either the battery in the SmartKey is discharged, the SmartKey is faulty or the starter battery is discharged. - Check the battery in ...

Inserting and removing a CD/DVD
Proceed as described in the "Audio CD/DVD and MP3 mode" section. ...

Roadside Assistance button
– Press and hold Roadside Assistance button 1 for more than two seconds. This initiates a call to the Mercedes-Benz Customer Assistance Center. The indicator lamp in Roadside Assistance but ...