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:  - ...

Activating/deactivating the radar sensor system
The following systems are switched off when the radar sensor system is deactivated: • DISTRONIC PLUS • BAS PLUS • PRE-SAFE® Brake • Blind Spot Assist • Active Blind Spot Assist USA on ...

Problems with the cooling with air dehumidification function
When you press the button, the indicator lamp in the button flashes three times or remains off. You can no longer switch on the cooling with air dehumidification function. - Consult a qualif ...