Headunit Problems

[vasili.liolios]

Hi Guys
I currently own a 2004 Subaru Liberty Spec B and has a pioneer headunit. But with installing this headunit I am now not able to use my buttons on my steering wheel or the buttons on the little screen in the centre that brighten up the display on my speedometer. Is there anyway I could fix this so I am able to use all of my buttons?

Cheers
Vasili