erikankrom

I haven't read through all 11 pages of this forum, but I did find the diagrams and instructions very helpful, with one additional point of clarification. There are TWO gray wires (without stripes) on the 2015 GMC Sierra 1500 SLT Crew. One is around 20-22 gauge wire, the other is around 18-20 gauge. The one you want is the thicker of the two. It may be buried in the bundle of wires, just keep looking for it. If you want to be sure, use a computer safe circuit tester. Unfortunately, I didn't have one on hand, so I learned the hard way.

So I think I've found a potential solution, and I have 2 of the 3, with the ACDelco part on order: 3 separate harnesses/kits required: Metra 70-2057 - GM 2014+ Amp Bypass Harness (Non-Bose) Metra 71-2107 - GM 2015+ Factory Radio Plug (only large green adapter is needed for radio/speaker wires into amp location) ACDelco PT2641 - GM Original Equipment Black Multi-Purpose Pigtail With all three of these, I should be able to create an adapter for the bose system that will be flexible enough to meet my needs. I can see how my wiring is going to be fairly specific to my install, but these 3 adapters combined will prevent me from splicing into factory wiring, just using the existing harnesses. Also, for the front/rear door speakers, the Metra 72-5600 should work just fine. I tested on my truck, and while it's not made to fit exactly, the fit aligns, just doesn't have any clip to hold it in place made specifically for the factory wiring. Haven't yet found an adapter that works for the dash speakers. After I get the adapter wired up and tested, I'll post a followup.

Yes, http://www.metraonline.com/part/70-2057is the amp bypass for non-bose systems. The non-bose don't have all the extra processing in the amp, so are much more flexible. I wish mine were that easy. With a bit of work (and some non-used wires, this harness takes care of the female half of my connection (from the body wiring to custom harness), I just need the male for the other half of the harness plugging into the amp.

Thanks @fondupot. I've actually got a basic LOC with a posi-tap spliced into the subwoofer output of the Bose amp feeding my subwoofer amp and dual 10" subs for now. The 5-channel and AudioControl are both mounted, but not yet used. I'm wanting to add the AudioControl and a 5-channel Amp for additional signal summing, crossover, and power to the rest of the system. I haven't noticed much of the Bose crossovers kicking in with the subs yet, but I'd just like an overall cleaner signal going to both amps and all speakers with the AudioControl LOC. I'm thinking it's possible, just being impatient waiting for an adapter from Metra.

I am trying to add an AudioControl Line Output converter, and 2 separate amplifiers to my existing 2015 Sierra Crew Cab SLT Bose system. I'll use a 5-way amp to power the front, rear, and console subwoofer. I've got a sub amp to power dual 10" subwoofers in an enclosure under the back seat. I've looked everywhere for a 2014-2015 GMC Sierra aftermarket harness for Bose systems without any luck. Basically, I would like to fabricate a custom harness so that I don't have to totally splice into the existing wiring. That way, I can simply keep my existing bose system in place, and if needed for warranty or if I end up selling or needing to yank out the audio system, still keep factory in place. Also, I can't completely remove the factory Bose amp, because it handles other processing, like bluetooth, door chimes, etc. The amp will continue to power the two dash speakers, and have other low level inputs from the factory head unit, but all of the other speakers outputs (from Bose Amp) will be summed by the AudioControl LOC, then output via RCA to the two amps, with speaker level outputs from the amps back to the custom harness and out to the speakers. I've found an adapter from Metra for an amp bypass (http://www.metraonline.com/part/70-2057), which was made for non-bose, but will work for the female side of the custom harness on the bose system, but I need the male versions of the adapter as well to connect to the amp. If I could get the harnesses identified as #3 in the photo below, I think that will work. Then I just do all the splicing and electrical connections on the custom harness instead of factory wiring. Any idea how to find/order it?

I just purchased these for the speaker connectors in my 2015 Sierra: http://amzn.com/B001OAB6BW While they aren't EXACT fits, they do work, pins in the same places, casing and tabs in the same place. It's a snug enough fit where you don't need a clip on the harness.