I have an Fiat Tipo 1,6 dgt -90, the problem is that the speedometer is in miles. I think there is some way to change them to km because when you press the "test"-button you can see the kilometres per hour marks showing. so how can i switch it?

I believe there is a miles / KM button to the RHS of the display buttons,
was on my Tipo and Tempra's - RHD ..!!,
your location may be different,
good luck,
Charlie

Theres no button for that in my car, i think i have to change places of some wires?