I got to exploring my car the other day and stumbled upon the OnStar module in the trunk of my 2001. From the short bit of research, I think that it was the GPS module (possibly cell phone - could not tell). There is a small connector that appears to connect these to the front of the car. Then I had an idea. The system in this car is now useless because OnStar dropped their analog systems when the government said they did not need to maintain it (and this system cant be updated due to GM changing the control protocol of the vehicle). So what if I were to find the wires responsible for the phone part of the system and solder them to a bluetooth headset to basically use my cell phone as the phone for the car.

Does anyone have any input on this? Or better yet, a wiring mapping as to what wires do what in the OnStar system. I kinda want to go crazy and just try it - save for the fact that OnStar has this fancy feature where they were able to turn off the car remotely and I don't really want to accidentally activate that and have to pay to get the system removed completely.

 

I say go for it.That sounds like a great idea.I coulda never thought of that.

 

I am presently looking for the schematics or a probe that can 'sound' the wires without removing them from their plug. Like I said, I don't want to have a hefty repair bill sitting in front of me for stupidity. Think it would be in the service manual?

 

I do believe GM/OnStar can update the system. I gave them a call for my '01, and they said the dealer could install the new digital unit for like $215.
I like the idea though, if you get it to work, definitely do a write-up and post pics/wiring schematic.

 

Thats interesting... From everything that I have read, the new digital system is not compatible with the controller interface for the car (supposedly GM made a change internally to the bus structure)

Does anyone know if there a way that I can get the voltage running across the lines without removing them from their harness?

 

You should be able to backprobe the connectors. I use paperclips. Bend the paperclip straight, then push the end of it into the harness where the wire goes in. Use it as your contact point for the probe on your meter.