So, I wanted to do this same thing with my 2015. I have a JL power wedge and while I felt that the system, overall had really good sound, some music was really lacking on bass. I listen to a lot of classic rock as well as some newer rock, country, etc.. it seems that most newer stuff and even some older music that had lower frequency in the track would sound pretty good with the factory sub. However, some music that maybe was a little higher on the low end seemed to be "bass missing". As if the bose amp is set to only pass say 40 hz and lower (estimate) So, I had this power wedge that I had installed in my 2012 Malibu and I had traded it in on the new impala. When in the malibu, it added bass everywhere and with the remote adjustment knob, I could tailor it as needed. I searched everywhere and couldn't find anything about the wiring on these newer models until finallly! I was able to run across this schematic for the output wiring on the bose amp. It is as follows and is the ONLY diagram I could find that color matched all the wires on the amp.
Left Front Speaker (+/-) blue - brown/blue (wfr); yel/blue - yel/gray (twt) +,- amp in trunk R side, gry 8 pin plg, pins 3-7; grn 16 pin plg, pins 5-13 Right Front Speaker (+/-) yellow - yellow/blk (wfr); brn/grn - pur/brn (twt) +,- amp in trunk R side, gry 8 pin plg, pins 2-6; grn 16 pin plg, pins 4-12 Left Rear Speaker (+/-) green - green/black +,- amplifier in trunk R side, green 16 pin plug, pins 7 - 15 Right Rear Speaker (+/-) white - blue/black +,- amplifier in trunk R side, green 16 pin plug, pins 6 - 14 Center Channel (+/-) yellow/wht - blue/yel (F); white/blk - yel/brn (R) +,- amplifier in trunk R side, green 16 pin plug, pins 3 - 11; 10 - 2 Subwoofer (+/-) blue/gray - green/blk (L); gray/blk - green/pur(R) +,- amp in trunk R side, blk 8 pin plg, pins 1-5; grn 16 pin plg, pins 8-16 Aux. Audio Input Left (+/-) gray - purple +,- radio, gray 20 pin plug, pins 9 - 8 Aux. Audio Input Right (+/-) lt. green - purple
So, I used the wires going out to the factory subwoofer as line level inputs for my sub amp. Here is the problem. While it does work just fine, I am using inputs that the bose amp is already processing. In other words, my new amp is only getting signals that the bose amp is "deeming" as a bass signal. Even with turning the control or remote knob up, it only adds a little more low end. On songs that may not have the same low frequency as some newer stuff, I am not able to bring out the bass, as I was able to in the malibu with the same sub and amp, because the bose amp isn't passing it through. What is needed here is a diagram for the inputs to the amp so we can take a full range signal and let the new amp decide or filter the bass appropriately. The diagram I found describes each and every wire that comes FROM the bose and it covers every single wire that is plugged into it! There isn't any other wires coming into the boss amp, at least that I could find, that could be actually inputs. I have heard that starting in 2014 on this new Elippson lll platform (same platform as the Buick LaCrosse and the Cadillac XTS) they have gone to a new type of bus or network type wiring. I'm not clear on what all that means, but just in front of the bose amp is another, similar sized device that has a large single plug going into it. I'm not sure if it is on star, part of the sound system, satellite or what. But I couldn't find any diagram for this anywhere. Maybe some of these wires are the inputs? Maybe to have better bass control (or freedom) would be to use different output wires from the bose, rather than the sub wires? I'm not really sure what to try next and I have had the sub installed this way since March. I just figured I could wait until more people figure this new one out, and go from there.
Last edited by Utah LTZ; 07-03-2015 at 10:48 AM.