subzero999

I have just replaced the factory radio in my 1997 legacy s/w with a new headunit. After connecting the speakers/12v continous lead/acc and ground wire I am left with 3 wires. I traced the green/yellow as the power antenna and hooked this up accordingly. The 2 leftover wires from the subaru loom are a thin black and a white/green, i'm not sure what these are used for. My problem is the power antenna does not work now. The motor makes a noise but it does not go up or down. Any ideas? Thanks