OK,
I'm getting hooked on this computor-car integration stuff. While I'm pulling of faceplates, poking wires etc to try to hook my steering wheel remote directly to my riocar I want to attempt to do the same with my Onstar. The first piece of advise I need...... is it possible. Let me give the facts as I know them:

When onstar is activated it sends a signal via a class II serial data circuit to the headunit (thru a single wire) to mute the headunit. The voice is then played thru the amplifier. I can easily wire the incoming sound to the riocar aux. inputs. What I'd like opinions on: Is there a possibility to wire a class II serial circuit (single wire) to the riocar's serial input and find the signal used to mute the audio.

(yes there are convertor boxes I can but which I can hook up to the mute and use mlord's new hack but I'm addicted)