See also:

Mobile communication devices in the vehicle
Mobile communication devices in the vehicle It is not recommended to use mobile phones, such as mobile phones without a direct connection to an external aerial in the vehicle's passenger comp ...

Remove unnecessary cargo
Additional weight increases fuel consumption. ...

General malfunctions
▷ CD/DVD changers and players have been optimized for performance in vehicles. In some instances they may be more sensitive to faulty CDs/DVDs than stationary devices would be. ▷ ...