I would think you can just unplug the Onstar equipment (there are a couple of modules). When I had mine unhooked I didn't get any strange messages, but I don't have the phone either. I'm not 100% sure, but I think the boxes are mounted on a rack behind the back seat. In some later model cars they combined the boxes (the satellite receiver and the vehicle integration module) into one unit and mounted it on the package shelf, but I think in '99 it would still be 2 boxes 'strapped' together with a mounting bracket.RonWa said:Any idea where the on star equipment is?
The handset is in the console, and a mic above the windshield.
I would assume the phone is somehow attached to the sound system but don't know where.
Thanks for any help.