Automatic distance regulation, using radar sensors to maintain the required distance between vehicles ahead by braking and accelerating. Approximate control range: S tronic/tiptronic transmissions 0–155mph.* In conjunction with S tronic or Tiptronic, includes Stop&Go function, where the system brakes the car to a stop. The driver can select from 5 distance thresholds and influence the systems acceleration behaviour via Audi Drive Select. Vehicles with S tronic and tiptronic transmissions also feature, Traffic-jam assist which detects vehicles ahead and on adjacent lanes to assist with the braking, acceleration and also steering up to approximately 40mph, to keep the vehicle in lane.