2001 Tahoe Head Unit Install Help

This is probably a dumb question, but I am installing an Alpine 9883 in a 2001 Tahoe without Bose, with Onstar. I have everything hooked up and I am getting power and everything seems to be hooked up correctly but I am getting no sound. The Tahoe does have an after market amp that is behind the glove box. On the wiring harness there is a blue wire (that I believe is the power antenna that is not needed for this vehicle) and the alpine wires have a blue wire (also power antenna) and a blue/white wire that is a remote turn on. It seems that there should be something else on the harness to match up with the blue/white that would give a signal to the amp. Seeing as how there is not, do I need to unplug the two connections going into the factory amp and then cut the wires off of their harnesses and connect the speaker wires together......essensitally just cutting the factory amp out of the equation?

Any help would be greatly appreciated. Thank you!

I would say don't cut anything get a wiring harness, because if its being amp'd there may be no sound because the amp isn't receiving anything.

I do have the wiring harness for the radio which is all hooked up and I did not buy any of the on-star harnesses because I do not really care to have on-star. Maybe I should not be calling it a harness, I am talking about the connections going into and coming out of the factory amp. If there is indeed no way to get a signal to the factory amp from an after market head unit (which does sound a bit strange to me,) then I would think that if I un-hooked the input and output that are connected to the factory amp and just spliced the speaker wires together I would be by-passing the factory amp and the speakers would be then working solely off of the head units power. Does this make more sense?

Thanks for you input.

i had the same problem on my 02 w.o bose and w.o onstar, my problem was the amp turn on (blue/white) wasnt hooked up good, these cars have a stock stereo amp which still needs a signal to turn on. i would not cut the harness off, i went through all the same problems. from what it sounds like you say there isnt a amp turn on (blue/white) coming off the stock harness??

Exactly! The only wire that is not being used on the harness is the blue power antenna. In another forum someone told me that there is a pink wire on the on-star harness that is the remote turn on for the amp (which is a smaller harness that connects to the factory headunit that I guess you did not have because you did not have on-star.) I have asked him if I have to cut the pink wire off of the on-star harness and hook it up to the blue/white on the decks harness, but I have not recieved a response yet.

Well that is what the problem was. The remote turn on for the factory amp is on the smaller harness (the on-star harness) and is a pink wire. I had to cut that pink wire off of its harness (which I am no longer using because I do not care to keep my on-star) and connect it to the remote turn on wire on the decks harness (in this case it was blue/white). So everything is working as it should now!

Thank you for your help.