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LLJ Customs Harness - choosing correct options

Var Nazari
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Var Nazari Enthusiast

Var Nazari

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Posted

I'm going to be installing this SubThump box and amp combo, and I would like to purchase a harness from LLJ Customs.  

http://subthump.com/Chevrolet-GMC-Custom-Subwoofer-Boxes/Silverado-And-Sierra-Crew-Cab-Custom-Subwoofer-Enclosures-by-Subthump/2019Up-Crew-Cab/New-2019-New-Body-GM-Crew-Cab-Dual-1012-Downfire-With-Amp-Space-clone.html


I've reached out to LLJ customs twice and they haven't gotten back to me. Can you guys help me with choosing the correct options for the harness? It's for a 2020 Silverado LT, 8"  without Bose.

Here's the link to the harness. https://lljcustoms.com/store/ols/products/2014-2018-gm-t-harness-for-8-screens-without-bose-1418gm8

 

 

First option: Line Output Converter

I already know I want the LC2i with the bass knob

 

Second Option: Vehicle Connector Color

I don't know which connector they're talking about and how to find the color

 

Third Option: Harness Length

I don't know where this harness plugs in, so I don't know how long I need the harness to be to get to under the rear seat

 

Fourth Option: RCA Cables

I have no idea if I need these

 

Fifth Option: Extended Amp Turn On Wire

Again..no idea where this is plugging into in the car or if I need it extended

 

And finally, should I just skip the harness? What's it actually doing? Can I just do the wiring myself if I'm comfortable with soldering

davidr83 Enthusiast

davidr83

Posted
Posted
16 hours ago, Var Nazari said:

I'm going to be installing this SubThump box and amp combo, and I would like to purchase a harness from LLJ Customs.  

http://subthump.com/Chevrolet-GMC-Custom-Subwoofer-Boxes/Silverado-And-Sierra-Crew-Cab-Custom-Subwoofer-Enclosures-by-Subthump/2019Up-Crew-Cab/New-2019-New-Body-GM-Crew-Cab-Dual-1012-Downfire-With-Amp-Space-clone.html


I've reached out to LLJ customs twice and they haven't gotten back to me. Can you guys help me with choosing the correct options for the harness? It's for a 2020 Silverado LT, 8"  without Bose.

Here's the link to the harness. https://lljcustoms.com/store/ols/products/2014-2018-gm-t-harness-for-8-screens-without-bose-1418gm8

 

 

First option: Line Output Converter

I already know I want the LC2i with the bass knob

 

Second Option: Vehicle Connector Color

I don't know which connector they're talking about and how to find the color

 

Third Option: Harness Length

I don't know where this harness plugs in, so I don't know how long I need the harness to be to get to under the rear seat

 

Fourth Option: RCA Cables

I have no idea if I need these

 

Fifth Option: Extended Amp Turn On Wire

Again..no idea where this is plugging into in the car or if I need it extended

 

And finally, should I just skip the harness? What's it actually doing? Can I just do the wiring myself if I'm comfortable with soldering

The connectors are on the passenger side under the dash. If you lay on the floor and look up behind the glove box, you will be able to see. You simply unplug the stock connectors, plug the harness into the radio module and then plug the stock connectors into the harness.

 

They also have a video on YouTube pointing out the location. I don't have Bose and I ended up getting the aqua combo connectors. I added the extra length cuz I wasnt sure where my setup was going initially and I had plenty of wire left over. But I don't think the 4ft length would have made it unless I used the lc2i or something similar and mounted that up front and then ran RCA cable to the rear.

 

The RCA cables go from the lc2i to the amp. The extended amp turn on wire will be dependent of the amp location distance from the lc2i. My amp turns on when it senses signal from the regular speaker wires from the harness. I skipped the lc2i as my amp has a speaker line in connection built in.

 

If you skip the harness, you will need to find the speaker wires and tap into them to get signal for a line converter.

 

I technically didn't need their harness since my amp has speaker level inputs but I wanted the ease of the harness and not having to tap into any factory wires. It will be easy peasy to remove too. 

  • Thanks 1
Var Nazari Enthusiast

Var Nazari

Posted
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Posted
11 hours ago, dram1983361 said:

The connectors are on the passenger side under the dash. If you lay on the floor and look up behind the glove box, you will be able to see. You simply unplug the stock connectors, plug the harness into the radio module and then plug the stock connectors into the harness.

 

They also have a video on YouTube pointing out the location. I don't have Bose and I ended up getting the aqua combo connectors. I added the extra length cuz I wasnt sure where my setup was going initially and I had plenty of wire left over. But I don't think the 4ft length would have made it unless I used the lc2i or something similar and mounted that up front and then ran RCA cable to the rear.

 

The RCA cables go from the lc2i to the amp. The extended amp turn on wire will be dependent of the amp location distance from the lc2i. My amp turns on when it senses signal from the regular speaker wires from the harness. I skipped the lc2i as my amp has a speaker line in connection built in.

 

If you skip the harness, you will need to find the speaker wires and tap into them to get signal for a line converter.

 

I technically didn't need their harness since my amp has speaker level inputs but I wanted the ease of the harness and not having to tap into any factory wires. It will be easy peasy to remove too. 

Dude that is incredibly helpful. Thank you. 


So all that is left is for me to decide where to mount my LC2i. If I mount it next to the amp, I'll get a 10ft harness and short RCAs and I should be good to go. 

Var Nazari Enthusiast

Var Nazari

Posted
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Posted
1 hour ago, Booma1218 said:

I tried reaching out to him for a harness and they responded and said they were closed until September...Anyone else get this response?

I got that message from AIS, not LLJ

davidr83 Enthusiast

davidr83

Posted
Posted
21 hours ago, Var Nazari said:

Is this the audio module? Do I have the black and gray connector?

117037966_2081821225294963_586061717678512158_n.jpg

117194179_292221438777798_5190086763538460122_n.jpg

Looks like that second pic is similar. The sharkfin antenna cable looks like it's the one on.the left so very likely

  • 1 month later...
Ksmo367 New Member

Ksmo367

Posted
Posted

So I have the aqua and white, have a 2019 custom with 7” screen and ordered accordingly, however I unplugged the aqua and the harness doesn’t match up, am I missing something or did I somehow get the wrong harness?

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