See also:

Restoring the factory settings
Press the and buttons simultaneously for approximately six seconds until the battery check lamp flashes twice. ...

Setting the air distribution in the front/rear compartment using COMAND
The air distribution can be set using COMAND. ...

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