DISTRONIC, the optional proximity control, helps you keep the distance you desire from the car in front of you at speeds between 30 and 180 km/h. A radar sensor in the radiator grille registers the distance to and the relative speed for the vehicle ahead and, as the need arises, DISTRONIC automatically throttles back, applies the brakes lightly or accelerates to the speed originally set. Simultaneously, both vehicles and the distance between them are indicated in the instrument cluster display. If heavier braking is required, an audible signal is automatically emitted.