Needing help installing after market stereo
 

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I purchased this harness But There is a 2nd connector. Where do I connect the smaller connector? I need to connect the acc wire to have radio turn on. Please Help!!

The h3 does have onstar but not hooked up. I dont care for the chimes. It does not have any upgraded sound system just basic.

so all your needing to do is find out where to hook up the other wire so when you turn the key the radio comes on correct?

Well I have a stock one, but if I were to do it I would do it this way. I cant remember if the 12v or not. If they do, then just connect in to the positive wire that turns off and on, not a consistant wire. Thats the easiest way to do it or get a test light (screw driver looking thing with a light inside and you can poke into wires to see if it lights up) and go through wires till ya find one. I found one under my dash to the left of my steering column (just crawl under to see) for my amp... Its a striped wire but cant remember which colors off the top of my head.