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2014 Factory Amp Wiring Diagram

171453 Views 218 Replies 60 Participants Last post by  purplenova
Someone asked about wiring up a Line Output Converter using the 2014 Non-JBL factory amp wiring harnesses. The 2 harnesses that plug into the factory amplifier under the passenger side front seat have everything you need to install a LOC. I stole the idea from this post: Replace Factory amp powering door speakers (uh.. just a few pics). The OP had great pictures, but didn't include an easy to follow wiring diagram.

This method requires no modification to the truck, which is good for lessee's like myself.

First off, buy TWO sets of Scosche Model: TA02B OR Metra 70-1761, or other brand of Toyota factory radio harness.

The larger harness that comes with these kits will plug into the factory harnesses at the amp, although one will have to be slightly modified.

The first thing I did when I received the factory harness was to pull out all of the wires and pins from the Scosche harness so I could rearrange the wire colors. If you look at the pins (at least in the Scosche ones, I assume its the same with any), there is a little tab that you can push down with a small flat head screwdriver to remove the wire and pin. I rearranged the colored wires to correspond with the factory amp wires. The Scosche wires were also labelled. This is NOT required, but it made it easier for me to remember what was what. For those unfamiliar with car stereo wiring standards, here is the list:

Yellow 12V Constant / Memory
Red Switch / Accessory
Black Ground
Blue Antenna Remote
Blue with White Stripe Amplifier Remote Turn-on
Orange with White Stripe Dash Light Dimmer/Illumination
Green Left Rear Speaker (+)
Green with Black Stripe Left Rear Speaker (-)
White Left Front Speaker (+)
White with Black Stripe Left Front Speaker (-)
Purple Right Rear Speaker (+)
Purple with Black Stripe Right Rear Speaker (-)
Gray Right Front Speaker (+)
Gray with Black Stripe Right Front Speaker (-)

NOTE: These are only the aftermarket stereo standards. I haven't found a vehicle yet that followed these standards.

You will also have to cut one of your harnesses so the larger factory amp harness will fit. It should be self explanatory, but look at the tundrageeks post above for a picture. You will need to cut one of the sides of the harness. I used a wire cutter.

Now for the factory amp wiring diagram. The factory pinout diagram is a little confusing, so here is my explanation:

In order to follow this diagram, hold the wiring harness you bought so the tab is on top and you are looking at the pins (looking "into" the harness).

If you look at the Toyota Wiring Diagram, you will see color code abbreviations. Here is the translation:

B = Black
W = White
BR = Brown
BE = Beige
L = Blue
V = Violet
SB = Sky Blue
R = Red
G = Green
LG = Light Green
P = Pink
Y = Yellow
GR = Gray
O = Orange

Note: I have included the colors as listed in the diagram. I did not confirm the colors, they are just included for convenience. Also note there are two white wires on the 145 harness.

The smaller harness, J144, has the power wire, accessory switched wire, ground wire, and the outputs to the front door speakers.

J144 (Smaller factory amp harness)

Pin 1 - Front Right Output to Speaker (+) - Light Green
Pin 2 - Front Left Output to Speaker (+) - Violet
Pin 3 - Accessory/Switched 12v [Remote In] - Sky Blue
Pin 4 - 12v Constant [Power] - Red
Pin 5 - Front Right Output to Speaker (-) - Blue
Pin 6 - Front Left Output to Speaker (-) - Pink
Pin 7 - Ground - White and Black (NOTE: The factory wiring diagram says that ground is Pin 9, but I confirmed that Pin 7 is actually the ground. It is a white and black wire. )


Pin 1 - Front Left Signal (+) - Brown
Pin 2 - Front Right Signal (+) - Pink
Pin 3 - Rear Left Signal (+) - Light Green
Pin 4 - Rear Right Output to Speaker (+) - Red
Pin 5 - Rear Left Output to Speaker (+) - White
Pin 6 - Front Left Signal (-) - Beige
Pin 7 - Front Right Signal (-) - Gray
Pin 8 - Rear Left Signal (-) - Black
Pin 9 - Rear Right Signal (+) - Blue
Pin 10 - Rear Right Signal (-) - White
Pin 11 - Rear Right Output to Speaker (-) - Violet
Pin 12 - Rear Left Output to Speaker (-) - Green

If you want to power the factory speakers with your new amp or if you want to use factory wiring, you can run speaker wire to the output pins above from your amp. I tried both ways and ended up running new speaker wire only because I am picky. The factory wiring sounded good. The factory speakers also sounded surprisingly good when pushed with more power from my amp. I ended up running new wire because I put in component speakers in the front doors and wanted to keep the crossovers in the cab for easy access to the tweeter attenuation switch.

Because the J145 harness has two extra pins, you will have to manually plug in 2 pins into the factory amp harness. You can see what I mean in the following picture. Its a crappy picture of it all wired up before wrapping everything up and tucking it away:

The speakers in the dash still play, and actually add some nice fill. They are overpowered enough by my front speakers so they aren't an issue.

You could alternatively tap into the wires after the amp, but I was unsure how the amp processed the sound signal. If anyone else tapped into the signal after the amplifier, please post your results.

I installed an LC6I at the factory amp location. I did not remove the factory amp, as I wanted to keep everything as stock as possible, but it is obviously not plugged in. I am running a Kicker ZX700.5 amplifier which powers Infinity Kappa 60.9cs 6.5" component speakers in the front doors, with the tweeters installed in Platinum edition sail panels. My rear speakers are still factory, and they take the extra power from the Kicker amp surprisingly well. I built a custom box that fits under the rear seat and have a single 10" MB Quart shallow Mount RLP254 subwoofer installed. On retrospect, I should have built a dual enclosure and ran two of the subs. The one sound good, but I have to add some bass boost for it to be as loud as I like. I do enjoy the extra floor space for storage though.

Hope this all helps someone out there.


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i posted the how to here as well, back then i was frustrated with the lack of help (except from spider) that i was posting more that it was possible and economical and even the most efficient way to improve the sound. but good job on providing more details, should post in the how to i did so people get a better idea....
I dont remember what I did now. I do plan on pulling the seat up and checking the install as if I think i went from the 4 channel amp to the sub amp instead of using the lc7i. I dont recall the ground but cant imagine that toyota would of used the mounting as a ground and I cant imagine that I would of been careless and not used a proper ground for the lc7i.

I thought the pictures were on my imgur account for both posts. Also, I dont like deciphering the wiring so much because then it allows people to not test for themselves. over the years i have had so many people mis wire the phase on speakers or mix up ignition and constant. I always suggest verifying the wiring so you know for sure.
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right on, much more detailed on the wiring then I.

I should point out that when summing the lc7i for output 3 (sub) it appears to sum for inputs 1 and 2 also. atleast it did for me.
well as i understand you would "sum" the inputs for the sub woofer output so that it hs all possible signal to process and produce bass out of. If you were to somehow sum the front/rear left and right you would lose fade and or balance, which would be a downgrade of your ability with the stock system.

in your case bigdutchbag, it seems the amps and lc7i wasnt adjusted at all. my settings wont be helpful as we are probably using different equipment and listen to different music and other factors that would make settings different. in all honesty, I was never a sound system installer, my area was security and vehicle wiring. You would be better off having a professional sound system person adjust things.You should not have lost volume, in fact you should of gained volume in a properly adjusted setup.
gb42, maybe but I'd have to show you the amp settings to. next time I'm removing the seat I'll take a pic. it would still be better to have someone that knows how to adjust it then go off my janky install.
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sounds like your installation shop is janky. find a professional. probably need to adjust amp.
good advice debremus. For bigdutchbag, you might want to hold the shop that installed it accountable. most places wont warranty things IF you touch it. I dont understand how you could have left the shop without it working, thats just poor service that the shop provided you.
right on but they shouldnt have ever let you leave without finishing. if the rears arent working right because the inputs are being summed then fix that. but that isnt right either because the lc7i isnt getting a "mid" only signal. the fronts and rears are the same. have them fix it right.
didn't you replace the amp anyways? the stock amp should of been removed and any installer that knows the lc7i should know this... heck any installer that replaced the amp should know.
the problem isnt that the lc7i cant do be connected to the front or rears, the problem is that the SIGNAL you are connecting to the lc7i is mid/low signal. you would want to connect full signal to the lc7i and then send the output to the amp where you adjust the crossovers and such to dial it in. if you send low signal to the lc7i it wont open it up and give you full range.

if you replaced the amp and speakers theres no reason to keep the stock amp in at this point, its not running anything.
all you have to do is have them remove the stock amp under the front passenger seat. there you/they will find the wiring needed for the lc7i. BOTH the input to the lc7i and the speaker outputs from the amp are there.

no need to get frustrated, this is all pretty standard stuff, the shop surely knows this.
just unplug factory amp. period. the plugs in that amp have everything you need for the lc7i. the inputs go to the lc7i then the speaker side, outputs of the factory amp go to the aftermarket amp speaker out. take factory amp out, i can't believe this shop is making this that difficult. this should of been fix in ten min.
if the install was done correctly, you can simply unplug the white plugs on the right in the first pic and everything should work the same. Theres no reason to keep the amp when you added an amp to replace that stock one.
so its not installed right. go to the shop, have them unplug the stock amp, and ask them to make it work without the stock amp. they should know how this works. the signal coming off the head unit is plenty good to run the lc7i.... lots of us have done it.
they tapped into it after the amp, thats the problem. He unplugged the factory amp and the system doesnt work, that tells you they tapped in after stock amp.
the audio control people told in an email earlier it was fine to do it either way if i am not mistaken. for crying out loud, go take the friggen stock amp out and have it wired already!!! this is so damn annoying! many people have done it by taking stock amp out, it works and works well. GO TAKE OUT THE FACTORY AMP!!!!!!
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right on spider2k. it isnt the best but its definitely an improvement over the stock. he could get away with just telling shop to connect this and make it work WITHOUT the stock amp.

color codes are odd but definitely something you could figure out with their two letter codes.

in the end this situation shouldnt of made it to the customer, the shop really looks bad. come to find out since they left the stock amp in, they had to locate the 5 channel amp under the driver seat. had they just taken the stock amp out they would of likely had plenty of space under the pass. side front seat. that would have minimized the install too.

I vote for having them refund the install and doing it yourself, common sense and patience you could likely do it.... or take it to another place, hell a best buy could do it.
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So after all this shit and information I gathered from you guys (especially taillight) I went back.......
haha thats f'd up. lol

just joking, but make them fix it.
.....I pulled signal from the amp output. I don't care what anyone says, the signal doesn't have the same voltage on the input side, so that is not where to pull it. Heck, the AudioControl manual even says in caps, DO NOT pull signal from in between OEM HU and OEM Amp... pull after OEM Amp......

you are right the voltage is different, its not amped. thats exactly why you are using the converter. you have adjustments to compensate for the difference.

Its very funny or should i say ironic, no one wanted to help me (but spider2k provided the factory diagram) when I started this. everyone said it couldnt be done, it wouldnt sound good, people said you have to replace all the speakers....blah blah blah. Now all these experts show up trying to reinvent the wheel. no offense meant to anyone in particular just wondering where all this help was a year ago when I did it.

when other people that clearly have experience with this and can explain real world application, you would think they'd be listened to over some manual that wasnt written for this specific application.

ok, end rant here thanks for listening.
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ls1steve, started this process of replacing the stock amp. a year ago in my truck. no one helped no one knew what to do with this wheel that was invented already and in fact insisted it couldnt be done. everyone said the speakers couldnt handle it.. I and then subsequently we, have proven that wrong.

anyways. toypor isnt there a signal sensing jumper on the lc6i? i know theres one on the 7i. might want to try it, and if that doesnt improve things, you might want to split the remote that the lc8i is getting for the amp as well.
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