See also:

Malfunction
A message is displayed in the instrument cluster. HDC is not available, e.g., due to elevated brake temperatures. ...

Maintenance
The battery is maintenance-free, i.e., the electrolyte will last for the life of the battery. Your service center will be glad to advise you on questions regarding the battery. ...

Increasing or reducing speed
The speed can be changed in the range from approx. 4 mph/6 km/h to approx. 15 mph/25 km/ h by pressing the accelerator or brake pedal lightly. A target speed within the same range can be spec ...