See also:

Deactivating HDC
Press the button again and the LED goes out. HDC is automatically deactivated above approx. 37 mph/60 km/h. ...

Refueling
Always switch off the engine before refueling; otherwise, fuel cannot be added to the tank and a message will be displayed. Take all precautionary measures and observe all applicable regulation ...

Look well ahead when driving
Avoid unnecessary acceleration and braking. By maintaining a suitable distance to the vehicle driving ahead of you. Driving smoothly and looking ahead reduces fuel consumption. ...