I have been doing some research and im finding out that what should be a simple aftermarket stereo installation, is quite the opposite. Has anyone successfully installed an aftermarket stereo in a 1999 STS? I've been hearing so many things with the wiring, and the bose system, the security system, and the vehicles computers can all be affected. I would like to NOT by the 80 dollar wire harness if I don't have to. Any help would be great. Thanks.

 

It's a Cadillac and a STS so nothing is simple. Dash unit is merely a tuner so when adding aftermarket stereo wiring is of little value. You will need to run wires to make it work and possibly speakers too.

 

Yeah you right about it.Radio installation in STS is very critical.I am not knowing about it well.But an option for is that you can search about it online and then replace it.