See also:

System self-test
After you have switched on the ignition, the system carries out a self-diagnosis. WARNING A malfunction in the system has been detected if one of the following conditions occurs:  - ...

Problems with the rear window defroster
The rear window defroster has deactivated itself prematurely or cannot be activated. •► Switch off any consumers that are not required, e.g. reading lamps or interior lighting. When the ...

Function restrictions
For safety reasons, some COMAND functions are restricted or unavailable while the vehicle is in motion. You will notice this, for example, because you will either not be able to select certain ...