Elite Harness system layout

Base Connector | Accessory | Audio converter High to low (ALOC)

2014-2019 GM/GMC Work/Custom/Elevation trim Vehicles with 4" or 7" Screen LOC Base connector

In stock

Key Features

  • The base connector is what connects to the factory audio source. EX: radio, factory amplifier)
  • Can be used with a T-harness or a Loopback harness accessory
  • Abrasion resistant loom
  • 100% OFC copper
  • Vehicle OEM connectors
  • Constant 12v +/-
  • Retains ALL Factory functions as they are
  • Designed, Tested and Hand-built by us.
  • 5 year warranty guaranteed

Price :

$65 USD
You must agree with the terms and conditions of sales to check out.
This product is only available through our Custom Elite Harness Builder Program. (CEHBP)
Email: Support@lljcustoms.com
Text or schedule a call: 602-320-7004

Our 7" Chevy harness is designed to work with GM/GMC vehicles like a Traverse with a 7" screen or a Silverado with the Work Truck, Elevation or Custom trim level . It comes available in both style of harnesses, a T-Harness and a Loopback Harness. If you are planning on adding a sub to your Silverado we offer our T-Harness. You can add an LOC unit, like an Audio Control or Wavtech LOC, for a full plug and play set up.

If you’d like to amplify your doors or add multiple amps to your GM vehicle we offer our Loopback Harness. This was designed to allow you to keep using the factory wiring, NO cutting, NO splicing. Add an amp quick and simple without ruining your vehicles wiring or voiding your warranty.

Please verify the connector in the vehicle BEFORE placing an order. All Base Connectors that need to be returned, refunded or canceled due to the connector not being verified will have a Restocking Fee of $15. The connectors need to be in the exact same condition as they were sent in. Any damage or alterations made will void all exchanges and returns.


LLJ Customs 1618GMWV 2014-2019 GMC CHEVY OEM amplifier T-harness 
  • 2019 (HD trucks) Supported models must verify radio is SILVER behind screen before purchasing.
  • Does not support Vehicles with  8" or 4" Screens (only for 7"screen Work vehicles LS ) ! Measure Screen from BOTTOM LEFT to TOP RIGHT corners)
  • TRUE Plug and play 
  • All soldered and shrink tubed connection, wrapped in tesa tape 
  • 15inch of amp remote turn on wire included when purchased with an LOC unit
  • Option to extend amp turn on wire an additional 15 feet. 
  • Cut and hassle free, simple and quick
  • Please verify this is the harness for your vehicle by looking at the harness behind the screen
  • Volt 2014-2018 none bose
  • Silverado - WT, Custom or Elevation trim level 
  • Traverse (please check with support for correct connector)

Harnesses ordered with NO UNIT will come with wire ends only. The LOC is DOES NOT come included, it must be selected. Pictures are only a visual representation of the different options available.
Harnesses ordered with no LOC unit will not come with remote turn on.

BC Fitment and Installation Notes

Vehicle Fitment


  • CADILLAC | 2015-2019 | ATS | With Bose
  • CADILLAC | 2017-2023 | CT6 | With Bose
  • CADILLAC | 2016-202 | XT6 | With Bose
  • CADILLAC | 2016-2024 | XT5 | With Bose
  • CADILLAC | 2019-2024 | XT4 | With Bose
  • CADILLAC | 2020-2022 | CT5V | With Bose
  • CADILLAC | 2019-2014 | CT5 | With Bose
  • CADILLAC | 2019-2024 | CT4V | With Bose
  • CADILLAC | 2019-2014 | CT4 | With Bose
  • CADILLAC | 2024 | LYRIQ | With Bose
  • CADILLAC | 2015-2024 | ESCALADE | With Bose



  • CHEVROLET | 2016-2024 | CAMARO | With Bose or factory amplifier
  • CHEVROLET | 2015-2024 | COLORADO | With Bose
  • CHEVROLET | 2014-2024 | CORVETTE | With Bose
  • CHEVROLET | 2017-2023 | CRUZE | With Bose
  • CHEVROLET | 2018-2023 | EQUINOX | With Bose
  • CHEVROLET | 2023-2024 | EQUINOX EV | With Bose
  • CHEVROLET | 2014-2020 | TRAILBLAZER | With Bose
  • CHEVROLET | 2015-2020 | IMPALA | With Bose or factory amplifier
  • CHEVROLET | 2018-2022 | BLAZER | With Bose
  • CHEVROLET | 2023-2024 | BLAZER EV| With Bose
  • CHEVROLET | 2016-2023 | MALIBU | With Bose or factory amplifier
  • CHEVROLET | 2014-2024 | SILVERADO | With Bose
  • CHEVROLET | 2015-2021 | CAPTIVA | With Bose
  • CHEVROLET | 2015-2024 | SILVERADO HD | With Bose
  • CHEVROLET | 2015-2024 | SUBURBAN | With Bose
  • CHEVROLET | 2015-2024 | TAHOE | With Bose
  • CHEVROLET | 2018-2024 | TRAVERSE | With Bose
  • CHEVROLET | 2016-2023 | VOLT | WITH BOSE



  • GMC | 2018-2024 | ACADIA | With Bose
  • GMC | 2015-2022 | CANYON | With Bose
  • GMC | 2014-2024 | SIERRA | With Bose
  • GMC | 2015-2024 | SIERRA HD | With Bose
  • GMC | 2018-2024 | TERRAIN | With Bose
  • GMC | 2015-2024 | YUKON | With Bose
  • GMC | 2015-2024 | YUKON XL |With Bose
  • GMC | 2023-2024 | HUMMER EV | With Bose



  • BUICK | 2013-24 | ENCLAVE | With and without Bose
  • BUICK | 2013-22 | ENCORE | With Bose
  • BUICK | 2020-24 | ENCORE GX | With and without Bose
  • BUICK | 2013-19 | LACROSSE | With Bose
  • BUICK | 2013-18 | REGAL | With Bose
  • BUICK | 2018-20 | REGAL SPORTBACK | With and without Bose
  • BUICK | 2018-20 | REGAL TOURX| With and without Bose
  • BUICK | 2013-19 | VERANO | With Bose
  • BUICK | 2016-19 | CASCADA | With and without Bose
  • BUICK | 2017-24 | ENVISION | With and without Bose
  • BUICK | 2017-24 | ENVISTA | With and without Bose
BC connection location

At factory Bose amp



Front under center console

Under trunk floor

 Passenger side of trunk behind wheel-well

Driver side rear quarter panel



Behind rear seat mounted on back wall

Installation/Tuning & Notes

LLJ Elite System Installation Manual

Color Code Card & Bass Roll-off info


  • Some Bose amps have a GRAY connector instead of a BLACK connector. This harness will still work with your gray connector. It will have an offset tab, we will cut one of the tabs on our harness to fit your vehicle. If your harness has both side tabs please note the LEFT tab needs to be trimmed. 
  • Some Vehicles don't have a BOSE tuned amplifier but DO have a factory amplifier that use this same harness.
  • Harness ordered with an LOC/Processor includes a remote turn on cable. 
  • Chimes will not be affected.

Elite T-harness Accessory Options-ETA

-Must Have a Base Connector to use this Accessory (BC)

The question is always what is the difference between the T-harness and the Loopback and the simple answer is, the T-harness is ideal for adding a Subwoofer only/mono amp or in a situation where you plan to run your own wires from the aftermarket amp to your new speakers. More information in the next page.

Elite LoopBack Accessory Options-ELA

-Must Have a Base Connector to use this Accessory

Our Loopback is simply the best option for any installation. Not just do you get the SIGNAL from the factory source unit but it also comes with 12v DC +/- to power your LOC or DSP. It also has a RETURN side that feeds from your aftermarket amps output, back to the factory speaker locations via the factory wires. The Loopback can also be tied together at the end, closing the loop in essence making a T-harness so you can start small and grow without needing to buy more.

Elite GX:500 S.I.K Options

Our S.I.K kits were the first of their kind to ever exists in the 12volt market. A solution long needed but never provided. "You need new speaker wire," was always the answer. That's no longer true. Increase the output and performance of your factory system in under 30 minutes. Our design places the aftermarket amplifier in the middle of your Elite Harness System.

Take the factory signal modify, tune, amplify and right back to the factory speaker locations. The amps we provide as a choice, we have used over the years and know they will work well in the particular function. Meaning all you have to do is plug in connect power and enjoy. Furthermore if you want to add an amplifier for subs we offer the option to add an Active LOC to your harness for future integration. Check out more below.

-Most Have a Base Connector to use this Accessory

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What Is High Level or Low level?

High level : AKA Speaker level is an amp that can handle an input voltage of 8-40v. This high output is common in factory amplified vehicles or where the
max voltage of a head unit is more then 10v. This is normally identified by a pigtail connection point or via the RCA on the amplifier (must check user manual to verify.) Some amps have a switch for this. NOT all amps have this future.

Low Level : is 0-8v of signal voltage. This is most commonly found inaftermarket head units. or other aftermarket units that use can-bus. Most passive LOC units output 0-5v so they are considered a low level and are normally RCA to RCA. Modern day ACTIVE LOC units can output 0-10v of signal.

In conclusion an LOC works as an in line filter that lest you control the signal, its intercity and in some cases the playable frequency range.

If your amp takes a high level and it is within the vehicles factory output range then you dont need an loc unit and can wire in and out of your amp
directly. In some fords the signal can be flattened at the OB2 furthering the simplification of the installation.

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