new stereos and driving comp. display disappears problem

Hi,

Sorry for my english, but I+m trying to find help where ever I might get it.

So the problem is that when I changed new stereos to Xsara Picasso 2005, The control stick which controls volume etc. on the right side of steering wheel doesnt work anymore.

Is there any other way to control the driving comp. display (which shows how many km´s you can still drive before refueling etc.) than the button on top of the stick that doesnt work anymore?

Is is possible to "bypass" this somehow by connecting the wires from that stick to somewhere else? Any other way to make the display work?

Thanks for your answer.

,Tomi