The driver support uses approx. 40% of the foot brake's capacity. If the car needs to be braked more heavily than the driver support is capable of and the driver does not brake, the warning lamp and acoustic warning are activated to alert the driver that immediate intervention is required.
Warning
The driver support systems only warn of vehicles which their radar unit has detected – hence a warning may not be given, or it may be given with a certain delay. Never wait for a warning. Apply the brakes when the situation requires.