Auto Start-Stop makes sure that fuel is only used when the car is actually driving. When the vehicle comes to a temporary standstill, for example at traffic lights or in stop-and-go traffic, Auto Start-Stop saves fuel by switching off the engine as soon as the car is idle and the foot is off the clutch (manual transmission), or when the car brakes to a complete standstill (Steptronic transmission).
A signal in the Info Display indicates that Auto Stop-Start is active. As soon as the clutch is pressed (manual transmission) or the foot taken from the brake (Steptronic transmission), the engine turns itself back on automatically.
Auto Start-Stop never compromises driving comfort and safety, as it remains inactive if the engine has not reached its ideal running temperature, the interior has not yet been sufficiently heated/cooled, the battery level is too low or the steering wheel is being turned. A central control unit restarts the engine if required, even when the car is at a standstill -- for example, if the car starts to roll forward or if the windscreen becomes fogged. Auto Start-Stop can be switched off at any time with the push of a button.