See also:

Connecting headphones
You can connect headphones with a jack plug or operate them using the infrared interface. To enable optimal use of the infrared interface, use infrared headphones that comply with the IEC 61603 ...

Remove attached parts following use
Remove auxiliary mirrors, roof or rear luggage racks which are no longer required following use. Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption. ...

Check the tire inflation pressure regularly
Check and, if necessary, correct the tire inflation pressure, at least twice a month and before starting on a long trip. Low tire inflation pressure increases rolling resistance and thus raises ...