See also:

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. ...

Fuel gauge
The vehicle inclination may cause the display to vary. Notes on refueling, refer to page 234. ...

USB audio interface/mobile phone audio interface
At a glance It is possible to connect external audio devices. They can be operated via iDrive. The sound is output on the vehicle loudspeakers. Connectors for external devices ▷ Connection ...