See also:

Cleaning the wheels
Do not use acidic wheel cleaning products to remove brake dust. This could damage wheel bolts and brake components. Do not park the vehicle for an extended period straight after clean ...

Important safety notes
WARNING   The PARKTRONIC is a supplemental system. It is not intended to, nor does it replace, the need for extreme care. The responsibility during parking and other critical maneuvers ...

Immobilizer
The immobilizer prevents your vehicle from being started without the correct SmartKey. When leaving the vehicle, always take the SmartKey with you and lock the vehicle. The engine can be started ...