Can't really say because I haven't looked at the phone wires at all so far. I got the RNS-E adapter with support for the phone (and CDC) and IIRC there were 3 wires in that plug. AFAIK, OnStar is nothing else than a phone kit (from a HU point of view). Proxus had a Parrot connected to his Symphony II and after the upgrade using a RNS-E adapter with phone support it worked just fine.TeddyBGame said: