GMT900 Bose Premium Amp to Luxury Amp Upgrade

[Reebok59]

Bill,
You are correct that it should have worked (front speakers only) if the head unit indeed needs no reprograming. From what I understand, the prem and lux amps work totally different with different input levels from the head unit. I would think your head unit needs to know which amp it is hooked up to. If that is not your problem, your amp may be bad. I fried my first amp by hooking it up to my non-reprogramed head unit and powering it up!
Good luck

 

[roadcrew]

Hey Scott,
I may have just realized something. I recall that you said your vehicle has RSA and therefore GMLS will already be present on A6. My truck however, does not have RSA. I noticed in one of the links you referenced where "licensetokill" picked up GMLS from behind his radio and put a jumper down to A6. I wonder if that could explain why my lux amp is not playing? Could that be needed to trigger it?
Bill

 

[Reebok59]

Yes, definitely need GMLS connection. That is what turns the amp on and controls the volume and every thing else.

 

[roadcrew]

Hey Scott,

Success! Yi-peeeeee! My second lux amp arrived. . .turns out the first amp, like yours, was bad. Now I just have to get the rear speakers to join the party, and I'm done! I'm thinking since I got a Y91 harnesses with each amp, I might harvest the pins/wires from one J108 to add to the other and connect the rear speakers that way (rather than cutting in behind the kick panel). I recall you mentioned pulling pins from these connectors. . . I've done it before with older GM plugs where you just bend the metal wings over by shoving in a paper clip. But for the life of me, I can't figure out how to get the pins out of these. It looks like you have to pull a little flat plastic tab forward for each pin. . . I can get the pins halfway out, but from there I can't see what's holding them in. I can't pull them out, nor can I push them out the bottom. I'd prefer NOT to break the J108 plug to get the pins out. Can you describe how they come out? Do you cut the wire and push them out the bottom, or pull? Is there some other trick beside the little plastic tabs that release them?

Thanks man!
Bill

 

[Reebok59]

Yes, there is a plastic retainer inside the connector. If you look close at the connector itself, it will come apart in two or three pieces. You can completely or partially take it apart and the pins will come out. I found this method eaiser than the paper clip method.

 

[tights24]

I hope you don't mind if I piggyback into this thread and ask a question as it seems you did quite a bit of work on this and have had awesome results. So first, thanks for the write up, pics, and details. Now, my question is this. I see you referring to regular and luxury amps and I saw the picture of the two side by side. I have a yukon SLT with the bose system and rear entertainment but no nav. I have pillar speakers as well as a center channel. Does that mean that my amp would currently be the luxury amp to start with? the reason i am asking is because I think a channel is fried as I have no significant sound coming out of my left front and rear door speakers. I heard a loud pop a few months back, and ever since it hasn't sounded quite right. lol. My guess is i fried a portion of the amp. All I am trying to avoid right now is ordering the wrong replacement amp and getting my console torn apart only to find that I have the wrong one. lol. Thanks.

 

[Reebok59]

I would be willing to bet you have the Lux amp since you have the center channel. You can call your local GMC parts counter and give them the last 8 digits of your VIN and they can tell you the part number of your amp and if it is a Y91 Lux amp or not. Also inside your glove box there should be a Y91 RPO Code if you have the Luxury Package. Either way, you need to know your P/N before you order a replacement amp to make sure you get on that is compatable with your system. Call GM parts or remove your console. Good luck.

 

[tights24]

Thx reebok, completely forgot about the codes in the glove box. smh. lol

 

[tights24]

Just an update after reading through this thread again as well as the Sierra thread. I have no idea why I thought I had a center channel, but I don't. I have all of the same RPO codes as you except the Nav code. My glovebox shows UQA, U2K, U42, UK6. I assume this means I have the premium amp and not the lux amp. I'm thinking now that my best bet is to open up the center console and take a look at my amp and just try to find one with the same part number that works. lol. regardless, thanks for the help and all of the info you posted. I probably will not go down the path of actually adding speakers. I just wish I could use the lux amp to simply add better sound to the existing 6 speakers and make sure that my rear DVD works and speakers controls were all the same. Oh well.

 

[roadcrew]

Hey Scott,
After that advice you gave me about the J108 connector, I took another look and yes, it was very easy to disassemble once I removed that blue "comb" that retains all the wires at the back.

Everything is working beautifully now, got the rear door speakers connected, but I noticed something curious. I can't fade between front and rear. When I move the fader control full rear I get silence. But when I move the fader to neutral (midpoint) the front/rear door speakers have equal volume. It's as if the four door speakers are on the front channel, but they're definitely not. I can live with it (like your muting issue) but like you, I'd like to have full functionality if possible.

My lux amp came out of a late model Yukon. I don't know how SUVs are set up. . . could it be that maybe fading occurs between the four door speakers and the d-pillars? Does yours fade that way? I don't have d-pillars because I'm in an extended-cab truck, so I'd have to hook up a couple spare speakers to try it. I've triple-checked the wiring and my rear speakers are definitely on the rear outputs. The only other possibility is an issue with my head unit. Any thoughts?
Thanks.
Bill

 

[Reebok59]

Bill,
I have been racking my brain about what could be causing your problem. I am at a loss. It is either your head unit or something to do with how you wired your rear speakers. For my SUV, the rear door speakers and the d-pillar speakers fade together as rear speakers even though they are wired on 4 separate rear channels. And the front door speakers, a-pillar speakers and center channel speaker fade together as front speakers even though they are wired on 3 separate channels. As I understand it, you wired your rear speakers through the 108 connector on your stock wiring circuits. I would recommend using a test speaker(s) wired directly out of the amp (not through the 108 connector) and see if it makes any difference. All the LUX installations have the rear speakers wired directly out of the amp and not back up through the dash where the circuits run through an INFOJMPR. It should not make a difference but it is the only difference that I cam think of that could be causing your problem other than the head unit.
Good luck, hope you get it worked out.
Scott

 

[rebel222]

Hi Scott,

I joined this board because of this thread. Thank you for this write up. It is extremely helpful. I am in the process of upgrading my premium system to the lux system in a 2014 yukon. I have a few questions that I was hoping you could help me solve. I purchased a luxury amp from a junkyard on eBay. It came with the console harness. However, there is one difference between the harness and your pin out, and I was hoping to understand this extra wire and it's purpose in the harness that came with the lux amp, it has a yellow wire in pin A-8. Any idea what this could serve or where I can find out?

My second question/comment is a follows: In the wiring pin-out you provided, I have a difference. For the J2 connection at the luxury amp, I have J2-12 and J2-13 swapped in the harness that I received with my luxury amp. J2-12 is light blue and J2-13 is yellow/black in the harness I received. You have these reversed, and I suspect that it's a typo.

Third Question: Where does the VNC mic mount in the denali/escalade vehicles? I'm going to order one to attach to the new luxury amp, but I wasn't sure to where the wires should be routed?

Fourth Question: In my RSA connections, there is a green connector that goes to the back side of the center console. My original harness had 8 wires and two bare wires. In the Y91 harness, there are four wires and no bare wire. In the original hardness, the colors duplicate from top to bottom (i.e. if there's a brown wire in the top row, there's a brown wire directly below it). Do you have any idea why these would double up?

Fifth and Final Question: I'd like to make a connector to bring the low voltage signal from the radio to Lux amp instead of cutting up my non-Y91 harness. Can you help me with the part number for the connector and pins for this? If you don't have this information, how did you make the connections to pins J4-8, J4-15 and J4-16 at the back of the radio?

 

[swathdiver]

...a yellow wire in pin A-8. Any idea what this could serve or where I can find out?

Join ALLDATADIY and you'll have access to that and a whole lot more.

 

[Reebok59]

Logan,

You are most welcome. Glad to see the information is helpful and being used by others. Below is my attempt to answer your questions.

1st Question: I have no idea what this extra wire is for. I have not seen it in any of the 2007-2013 wiring diagrams I have reviewed. I checked another Y91 harness I have and A-8 is blank. Maybe it was added for some function in 2014. I can only recommend researching a 2014 Electrical Manual. Good luck with this one. I would be interested in knowing what it is for when you figure it out.

2nd Question: Good catch. My bad! I got the polarity and description right but the wire colors are reversed. What you have is correct. I have attached a corrected table. Thanks!

3rd Question: The VNC mic in my 2008 is mounted inside the console on the driver’s side just below where your knee would rest against it. The pic in my post shows the location inside the console. If your console has the mount location, it will have a small perforated “dot” that looks like a small salt shaker lid. I think it was relocated to the left front headliner in later years. If you look up at your headliner you will see three small speaker/mic grills (left front, right front and rear). The same head liner was used for all SUV’s (Chevy, GMC or Cadillac). All mine are blank grills. The UQA Lux amp uses one mic (console or left front headliner). The UQS Lux amp with the Surround Sound uses all three in the headliner.

4th Question: This is a really odd question and throws me for a loop. My non-Y91 harness had had eight wires and two bare wires (basically two shielded quad bundles) (two sets of BN, BN/WH, D-BU, TN, Bare). These are rear channel low level outputs from the radio. In the Premium System, these feed the RSA first and then double back to the Premium Amp for rear channel inputs. My Y91 harness only had 4 wires and no bare wires. In the UQA Lux System, the rear low level outputs stop at the RSA and are not amplified, therefore no shields are required (The amp only uses front low level inputs and creates the 9 different channels, i.e., “Smart Amp”). Now the UQS Lux System with Surround Sound is different. It uses the rear channel low level inputs (J4 connector on the Lux Amp) for the Surround Sound. Sounds like you may have a UQS harness. Does it have the J4 connector for the Lux Amp?

5th Question: I attempted to do the same but had trouble finding the pins in small quantities so I decided to cut up my non-Y91 harness. I did however find the pins and the 8-pin female connector for the rear speakers from Mouser.com. I was able to purchase the connector and 10 pins for a very reasonable price. Also had to buy a Delphi Packard crimping tool for like $30 bucks! If you look at the wiring diagrams for the radio/amp/RSA, you will see a set of part numbers listed for each “J” connector. You can search these part numbers at Mouser.com and view the “related items” to see all related pins and connector assemblies.

Hope all this helps. Good luck.

Scott

 

[Jonah52]

Anyone have their stock nose amp that they would part with? Mine has a bad channel or two causing rear speaker distortion

 

[olmie]

Very impressive insight on system details. I just got a 2018 Yukon XL Denali with Luxury Bose system (RPO = UQS, 10-speaker, IO6 head unit ... Denali package loaded with all bells & whistles) ... What I really want to do is get low level (RCA) inputs prior to the Bose amplifier to input additional aftermarket amplifiers for other speakers... using line output converters from Bose amp speaker wires has a number of drawbacks. I'd actually like to keep the Bose amp as part of the system to power sub in console and tweeters in read (D-pillars), with all other speakers / subs aftermarket, powered by aftermarket amps. I see wiring schematics for wiring FROM Bose amp, but nothing on inputs feeding TO the Bose amp that I could tap into for full range low level inputs... I've had good experience with PAC for OEM integration like this, but neither PAC, nor anyone else seems to make anything for the new GM Bose systems. Any advice on how to get a good pre-amp full signal without disrupting vehicle functionality?

 

[Reebok59]

Sorry, but I am not familiar with the new Bose systems. Sounds like you are making good progress. Good luck!

 

[Chateau Vin]

As stated, I started with RPO UQA (Premium 6-Channel Bose). All the Bose speakers for the Premium 6-channel system (including the Sub) are identical to the Luxury 9-channel system except the D-pillar speakers. So I had to change out the D-pillar speakers with the LUX Bose speakers from a Denali which are 3.2 OHM to better match the door speaker impedance as they are now on a separate channel. When you upgrade to the LUX Amp you get 9 separate channels including a Center speaker. So I also added the OEM Bose 3.35 OHM Center Dash speaker inside the Driver Side Console Kick Panel. With the LUX Amp, the stock Bose Sub comes alive. Huge difference! It won't rattle the windows or side panels but the rearview mirror will vibrate and you can feel it in your gut! The PREM Amp was so wimpy, I didn't know I even had a Sub until I did some research on it. I am very happy with the clear crisp sound and power the system now delivers.

UQA-Y91 = Premium Non-Luxury Speaker System (6-channel Bose)
UQA&Y91 = Premium Luxury Speaker System (9-channel Bose)

The difference is the LUX Amp and the D-pillar speakers (and of course a little wiring, a VNC MIC and reprograming of the Radio).

Could any time be saved by sourcing a complete Denali Lux HU and center console , wiring harmess and pillar speakers . could this be a plug and play
with a GM dealer system reboot?. [A 2008 Denali system transplant to an 08 Avalanche LT.

 

[Reebok59]

Sorry, but not really. There is no plug and play solution. The wiring harness in the dash is different for the LUX and Premium systems and depending on truck or SUV, the body wiring harness for the speakers is different. As for the HU, the only difference is the programming. The Denali LUX HU is the same as the Premium HU. Wiring modifications are required for this upgrade. I would recommend thoroughly reviewing the wiring diagrams and PIN Tables referenced in this thread for a successful upgrade. Since you are considering upgrading an Avalanche, I would suggest reading Joe's thread on the Silverado Sierra Forum titled "GMT900 Bose Premium Amp to Lux Amp". His thread is linked in my references above. I recall Joe being able to do a HU swap with a LUX Console Harness with minimal wiring mods. Or maybe it was because he had a non-NAV HU, can't remember.

Good Luck,
Scott

 

[MCAT069]

This may have been covered already, but I did not see the answer, so I apologize if this is a redundant post; however, what is the 4th plug for on the UQS amp? I am in the process of gathering the needed supplies for this conversion on my 2012 Z71 and I picked up a 4 plug UQS amp for 20 bucks at the local wreaking yard.