See also:

Malfunction
A message is displayed in the instrument cluster. HDC is not available, e.g., due to elevated brake temperatures. ...

Adaptive brake assistant
In combination with the Active Cruise Control, this system ensures that the brakes respond even more rapidly when braking in critical situations. Refer also to Collision warning. ...

System limits
Check the traffic situation as well PDC cannot serve as a substitute for the driver's personal judgment of the traffic situation. Check the traffic situation around the vehicle with your own e ...