Pioneer GEX-P910XM Satellite Radio Receiver "head unit ip bus" Questions

...head unit) the IP Bus cable has an attached wire that runs to the power input harness. The other wire from the power input harness is the problem. I can't remember where it connects...positive always ...

...head unit, a sir-pnr2 satellite radio, and a now a i pod ib100 II. The head unit and satellite have been running fine for months. I bought the ipod part today(10/27/07). The guy at the store said to ...