2011 volvo radio steering wheel controls

ok as the title says i have a 2011 670 and it has the radio controls on the steering wheel. the prev owner installed an aftermarket deck and hardwired it in which is a pita but not really a problem but the steering wheel controls were not hooked up. i recently bought a new jvc deck for the truck for the build in xm feature and would like to hook up the radio controls. i dont care about the bluetooth buttons on the wheel but would like to get the volume up and down working as well as the song/station change. Does or has anyone out there hooked up theirs and know what wires are the controls. and what adapter i would have to buy. the only factory wires that still have a harness on is this yellow one with 2 wires that plugs into the back of the stock deck, all other white.orange stripe wires have been hardwired into the deck except 4. any help would be great.