I've been researching and looking at options on how to put in an aux input in the stock GM radio. It does not have XM, so I can't tap into that, I don't really want to have to slide a cassette in every time I want to plug in my Ipod.
The one thing that does lead into the radio that is an exteral unit is the Onstar.
I found that the Onstar goes into the back of the head unit with High and Low signal, but I'm affraid this is not audio quality. Has anyone looked at this as a means of adding a Aux input?
My other thought, so what makes the connection for the radio to switch to the cassette circuit? Does something get power or ground when the tape is slid in? Is it possible to add a toggle or even a relay that would allow the aux input to trigger the tape deck circuit to come on?
I have idea'* just no knowledge of the internal radio schematics