See also:

Steering wheel keypad
The four buttons on the steering wheel keypad can be used to control the audio system. The steering wheel keypad can be used to adjust volume, shift between preset stations and change CD tracks. ...

Electrical system
General information 12 volt system with a voltage-regulated alternator. Single pole system in which the chassis and engine block are used as conductors. The negative terminal is connected to the ...

Driving Dynamics: Engines
The Volvo S40 is available with a range of high-tech engines that reflect its role as a premium alternative. Three new engines joined the range in 2007: a 145 PS 2.0-litre petrol, a five-cylinder ...