See also:

Activating HDC
Press the button; the LED above the button lights up. ...

Safety switch for the rear
Press the button on the driver's door if children are being transported in the rear. This locks various functions so that they cannot be operated from the rear: safety switch. ...

The concept
This system projects important information into the driver's field of vision, e.g., the speed. In this way, the driver can get information without averting his or her eyes from the road. ...