GMC or GM traverse/blazer/terrain T-harness for adding a subwoofer (2018-2023)

This video was sent in by one of our amazing customers; to help others see how easy and simple adding an aftermarket amplifier could be using our plug and play T-Harness.
This harness is still been tested on multiple new GM/GMC vehicles and videos will be uploaded once we have finished testing them.
This video goes over the installation in a 2018 GMC terrain.
2019-2024 Aqua and Tan Harness:
lljcustoms.com...
2019-2024 Black and Gray Harness:
lljcustoms.com...
With Bose:
lljcustoms.com...
Contact Us :
Text: 602-320-7004
[e-mail]
Https://LLJcustoms.com
Thank you for watching !

[@dbrown4572]

Nice

[@LynnNew.]

How on earth did you get the plugs out in the first place. Mine simply does not pop out.

[@darkftforce]

i have 2018 traverse LT........it doesnt have bose sound system and no speakers for third row or in cargo area. the speaker grills in the cargo area (in the C pillars or very last pillars before the trunk door) are empty, 3rd row hears nothing, i have to crank up the volume all the way to high for them to listen anything, but then its too much for front and 2nd row. i wanted to install speakers for third row, just wondering what size and brand will fit in? i tried to search on internet, went to chevy dealership.......but found nothing. can you please help in suggesting any good quality speakers that would fit in, i dont want the latest or greatest or the most expensive ones, but decent sound quality. also do you have any idea that i have to install wiring for it or will it be there behind those empty grills? thanks for help and advice.

[@gerardobernardino1092]

Hey bro I had the same issue as you. I did a custom speaker adapter using what was already on the vehicle I wasn't trying to spend $60 for replacement grills . I used 3 1/2 JBL's and parallel wired them to the rear door speakers.

[@darkftforce]

@@gerardobernardino1092 thanks for the advice, so it will fit 3 1/2 inch... Will it over burden the wiring when pair them with rear door speakers? Will it have any negative impact on vehicles stereo as it will have to power 2 more speakers on same wiring? Thanks again for the help and input.

[@gerardobernardino1092]

@@darkftforce when you remove the pillar cover you'll see this small square looking cover in place where the speaker should be. Remove that as clean as possible so you'll be able to use it as a bracket for the 3 1/2inch speaker you're going to put in. I believe I used 1/4 inch screws to put them back on with speaker in place. You can't use long screws as they will screw all the way through the pillar cover (almost happened to me). I'd send you pics of how mine looks but we can't post pics here. And as for your question, well I've turned mine up to atleast 34 and sounds loud and no issues whatsoever. I have JBL GTOS in front and rear doors. And JBL club 322 in the rear back pillars.

[@darkftforce]

@@gerardobernardino1092 thank you very much, that is very informative and will be helpful. Thumbs up! 👍

[@user-hb9jz7ne3w]

Will this work on a 2019 Cadillac XT4 without Bose? Similar body type from GM. Thanks!

[@lljcustomscaraudiofabricat7854]

Yes it will you may also have the black and gray so verify your colors befor you order

[@Finesse79]

Nice. But how did you remove the harness’s from the amp. I was hoping you would illustrate how you did that? I’m having an impossible time removing the harnesses from the amp. Car to share you accomplished the part? Thanks in advance!

[@lljcustomscaraudiofabricat7854]

Hello Finesse, there is a small lock tab that needs to be pulled back to allow you to press down on the connectors main locking tab that is white in color you can pull it back with your nail.

[@Finesse79]

@@lljcustomscaraudiofabricat7854 Excellent! Thank you. Another question if I may: Is that unit down there the radio module or is it the Amp? Thanks for your help1

[@jorgel.davila1973]

Do you have a amp install to Chevy Traverse? I need help!

[@cedricthomas4867]

Where can I get for my terrain I want to use an lci7

[@lljcustomscaraudiofabricat7854]

@@cedricthomas4867 our website at lljcustoms.com or at T-harness.com

[@chrisharris9195]

I need this for my 2018 terrain. Has Bose setup

[@lljcustomscaraudiofabricat7854]

t-harness.com/products/2013-2024-gm-bose-t-harness-r2g

[@JCRUZx91]

Does anyone know if it's easy to run wire thru firewall or is drilling necessary. I have a 2019 gmc terrain awd.

[@frostakathetruth]

On my equinox i ran the wire threw the firewall threw the big rubber boot with the other wires on the driverside.

[@Wrensspeedshop]

The plug that you said is your speakers. Are you saying that those wires go to the speakers in the car or that those wires have the signal for each speaker channel going through them?

[@lljcustomscaraudiofabricat7854]

both the signal is taken from here and can also be fed back using our ELITE Loop back system.

[@Wrensspeedshop]

@@lljcustomscaraudiofabricat7854 Do you sell a “T” wiring harness that would be needed in order to plug into the factory harness and receive the audio signal from the car? Once received and converted to the audio signal that I need as well as amplified, I would and then have the ability to feed back in to the stock harness. I hope this makes sense. I have my own amps and new components for the vehicle. Thank you.

[@lljcustomscaraudiofabricat7854]

@@Wrensspeedshop Absolutely that is our Elite loop back harness. It will feed signal and provide the return wires from the aftermarket amplifier back to the speakers via the factory wires

[@lljcustomscaraudiofabricat7854]

@@Wrensspeedshop lljcustoms.com/collections/chevy-gmc-cadillac/products/2019-2022-gm-gmc-elite-t-harness-without-bose

[@Wrensspeedshop]

@@lljcustomscaraudiofabricat7854 there is literally so much information to go over, is there any way I can speak to a sales rep? The last thing I need to do is order a harness and it is not what I needed. I need to be able to tap in to the factory harness, the signal side so that I can run input into my 4ch amp which is a SKAR, then be able to run the audio from the amplifier back to the harness that feeds directly into the car using the factory harness for simplicity purposes. I also need a way to be able to pull a low frequency for a a sub amp. I’m sure I can run rcas from the highs amp and use the Low pass frequency adjustment on the sun amp. It’s just like a text message I can say one thing but the meaning can be lost in translation which is why a phone call is so much easier. Thank you for getting back as quickly as you have.

[@jadon2709]

Nice job, could you also run a 5 channel amp to speakers and sub with this? Also did your car have the NCS?

[@lljcustomscaraudiofabricat7854]

Yes you can

[@michoacanomartinez5971]

Lo tienen disponible y precio por favor es para una gmc terrain 2019

[@Kyf713220]

What is the harness model number????

[@lljcustomscaraudiofabricat7854]

t-harness.com/products/2019-2024-gm-chevy-t-harness-aqua-tan-connectors-none-amplified-r2g?_pos=1&_psq=aqu&_ss=e&_v=1.0

[@superman0075]

Where you plug In your remote wire

[@michaelanderson6845]

I have a 2020 gmc terrain how do I get the plugs out to plug in the wiring harness

[@markell1757]

You gotta disable anc also or there’s gonna be a hum when you shut your doors

[@xxreptylexx]

I recently installed 2 amps for my stock speakers and a sub. I have a terrible high pitched noise coming from the speakers. It's not engine whine. It goes away after a bit turning the car off. So I believe it's some sort of electrical interference. Just have no idea where to start. Tried moving grounds. Moving sources. Everything! 2018 GMC terrain as well. Help!!!

[@johnnywang80]

Probably your ANC mics in the rear. You’ll have to unplug them.

[@xxreptylexx]

@@johnnywang80 specifically in the rear? We actually tried the fronts but no luck. What's the thought with the rears in particular? Thanks for the reply!!

[@johnnywang80]

xxreptylexx I’m not too sure why but look up “2019 Terrain ANC noice cancellation for subwoofer” and you can watch the vid. Maybe you can get an answer from them on why it’s the rear ones.

[@GeneralMillzz]

@@xxreptylexx Hey! Did you end up disabling the mics in the rear? And if so, did that help? Also, did you have any issues with disabling mics in the front? I came across some info that it could possibly mess up the Bluetooth somehow.

[@xxreptylexx]

@@GeneralMillzz I have now had my terrain for almost a year. All I can say at this point is I'll never do an aftermarket stereo again. I will just get the upgraded stereo from the factory. I have all sorts of problems with my terrain since putting all the aftermarket amps and subs in. To answer your question. I don't think we did unhook the back. But I cant fully remember at this point. Do you already own a terrain??

[@eddiecastillo8940]

Nice video! You know if the 2018 Equinox is the same installation? where'd you get the wire harness? I'm looking to install and amp. thanks

[@scope7466]

I need to know as well, but I only Have 1 big green clip and not a light blue one like he has in the terrain

[@ken14850]

In description

[@IRosesRedI]

Hey I’m interested in getting this harness for my GMC Terrain 2018. How may I purchase!? Thanks

[@lljcustomscaraudiofabricat7854]

All purchases can be made through our website or T-harness.com

[@Swartzhandiwork]

Where did you run remote turn on

[@lljcustomscaraudiofabricat7854]

Hello, the remote turn on comes from the LOC units like the linkDQ

[@andrewblanchard8214]

Were can I get one of those

[@joseandres5014]

So what adapter is being used in the video ?

[@lljcustomscaraudiofabricat7854]

Hello Jose, the customer is using an LC2i LOC with their set up.

[@jaydeethadon4998]

I wonder if this would work on a 2020 terrain

[@lljcustomscaraudiofabricat7854]

Hello Jay, yes this works for a 2020 Terrain as well. Send us an email to [e-mail], we can help you find the correct set up for you.

[@joshuamachnik7103]

@@lljcustomscaraudiofabricat7854 hello, i am in need of one of your harnesses for a 2020 Acadia. do you offer one?

[@Renowildfire1]

Need for a 2014 terrain

[@GHOST-rt8en]

How to delete the ANC active noise cancellation?

[@lljcustomscaraudiofabricat7854]

The modal will be under the center dash and we offer a bypass for that.

[@GHOST-rt8en]

I bought the same pieces for my gmc terrain 2018 but when I close the door I hear a lot of noise

[@mclovin-wd8hl]

Just cut the blue wire and that will disable the ANC

[@apschmidt2001]

Would this be similar in a 2012 Denali terrain with the factory pioneer sound system

[@lljcustomscaraudiofabricat7854]

yes it is. same harness but the pioneer radio is under the steering wheel.

[@apschmidt2001]

Can you send me a link to purchase... either im an idiot or something cause i can't find anything

[@deezy987]

Will this make the stock radio louder also ?

[@lljcustomscaraudiofabricat7854]

Hello, the simple answer is no. In this installation the purpose of the harness is to provide signal for the subs . If you want to add power to your speakers and add a sub you wpuld want to us our Loopback harness or our S.I.K gx500 kit

[@jadon2709]

@LLJ Customs Car Audio Fabrication L.L.C Do you have a link to the loop back harness your talking about? I wanted to add 5 channel amp. Thanks

[@lljcustomscaraudiofabricat7854]

@@jadon2709 yes we do, lljcustoms.com/store/ols/products/oem-loop-harnesses

[@kingsubaru2487]

What's the connectors pin out diagram

[@ken14850]

lol been looking for it any luck?

[@Mondo_0ne]

Is that similar to the kicker key?

[@lljcustomscaraudiofabricat7854]

Hi mondo, no the key is a small brick amplifier the lc2i is a high to low signal processor. The audio control ACM1.300 would be like the kicker key but better.

[@calvinburton6619]

Thanks for the video I went on the website looking for the plug and play converter. Not completely sure which one to get, if possible could you share the model so I can be sure to order the right one. Thank you

[@bvcrimson]

What harness is this on the website?

[@lljcustomscaraudiofabricat7854]

Hello, it is our 2019-2021 harness here is the link : lljcustoms.com/store/ols/products/2014-2018-gm-t-harness-for-8-screens-without-bose-1418gm8

[@andressandoval6299]

I got a subwoofer installed on my 2018 Chevy traverse and the truck is acting up like (abs) light has turned on climate control for the rear seat was disabled .. can anyone help please?

[@lljcustomscaraudiofabricat7854]

Hello Andrew, did you have the install done at a shop ? Do you know what they used to get the signal to your sub ?

[@speakerboxexpert]

does this harness bypass ANC?

[@GHOST-rt8en]

No, i got the same gmc terrain and I bought this harness but the ANC still cause me horribly sound

[@speakerboxexpert]

@@GHOST-rt8en i got one also, ended up unplugging the mic in the headliner. Didn't really need the harness, but it did make for a cleaner install. but it was easy to do without harness.

[@GHOST-rt8en]

I did the same thing but they have to do for the price of this harness

[@cjrd1993]

@@speakerboxexpert would this remove the ability to use the hands free call feature while driving?

[@calvinburton6619]

Actually I meant the harness

[@lljcustomscaraudiofabricat7854]

Hello Calvin, here is the link : lljcustoms.com/store?olsPage=products%2F2014-2018-gm-t-harness-for-8-screens-without-bose-1418gm8 Thank you