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2014 Factory Amp Wiring Diagram

171451 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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are you summing the front and rear? if so you have a front output from the lc6 with the front and rear input.

thers also a harness you can get that doesnt need cutting but i cant remember the number. i just dug around til i found one. i think it was one of the old import/jeep harnesses.
I was summing the third channel which was my problem. I was thinking backwards and thought the summing jumper would sum the main channel INTO the third channel so I could prevent the subwoofer from fading with front/rear. I reset the jumpers to separate and it solved the fading issue.

Now if I could just figure out how to prevent the subwoofer from fading with front/rear...

I'll try to find the harness you are talking about, that would be a helpful addition to the writeup. : PIE TOY03-F/MM 2003-up Toyota 12-pin Y-harness Cable : Vehicle Audio Auxiliary Adapters : Car Electronics

This harness actually looks like it would fit the larger factory amp harness, but can't say for sure. It's the correct number of pins anyway.
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....
Thank you for the original post - it was a perfect solution for me because I am on a lease and didn't want to make any modification to the factory wiring.

When I set out on the project I had a little frustration finding the factory pinout diagram. After I found the diagram, I was a little annoyed by how unnecessarily confusing the wording was on the diagram was. Anyone with a few installs under their belt could figure it out easily enough, as I was able to, but it would be incredibly confusing for a first time installer.

Also, Tillithz, I found that the factory ground pin did not work for me. I assumed it was because the factory amp is essentially grounded to the chassis via the bracket. I noticed that you were able to use the factory ground, did you have any issues? Also, I noticed there is an extra wire in the smaller factory harness at pin number 7 I believe and its colored white/black. It is not described in the pinout diagram. Did you ever figure out what that wire was?

I just remembered why I liked your post more than the one here: it was only because I could enlarge your pictures for a better look at the wires you used. Thanks again for the original post, it was very helpful. I need to get some shrink wrap tubes, it makes for a very clean install. I just ended up wrapping wires in electrical tape which made them a little less flexible.
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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.
It made NO sense to me that the factory ground pin didn't work, as it obviously works for the factory amp.

There is another wire (the white and black one I mentioned above) that is two pins over from the factory ground pin. I wonder if maybe that's actually the ground and the factory pinout diagram was incorrect... unlikely but it could happen. I sure didn't want to test it by grounding 12v through it without knowing what it was.

That's a good point about the wiring and testing for yourself. I wrote the post in the middle of a Vyvanse frenzy (ADHD medication, yes its prescribed) so I could have easily transposed a phase somewhere in there. I did post the factory diagram just in case for verification. Half the fun for me in an install is figuring it all out and the satisfaction of a customer install.
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Hmm thats what my guess was. I'll have to give it a shot, I guess i could always run a voltmeter across the white and black wire and the hot wire.
Thanks for this awesome information! 2 things to add ..

1) You labeling is slightly incorrect for pin 10 of J145. It should be Right Rear Signal (-). You have it listed as (+). I had to research the original wiring diagram quick.

2) I think using pin 9 as on J144 is probably why your LOC didn't work. By looking at the wiring schematic and pinout description, it appears that pin 7 is the actual ground. It is weird how everything is labeled as pin 9 is (AMP) Body Ground .. but everything seems to always go to pin 7 as being listed as (GND). I think you would have wanted to use pin 7 to use the factory ground. Being that I am wiring in an JBL MS-8 I'll probably run new PWR/GND anyways. But it'll be good to have those to at least initially power it up and test it.

Again, many thanks. This helped me a lot!
Thank you for pointing that out, I just made the correction in the original post.

I am going to try that pin and verify that it works. I had suspected it was the unlisted wire that was actually the ground. I am still curious what Pin 9 actually does... it could have sucked if it, at the very least, blew a fuse when I used it as the ground pin.

I am glad this post is helping, and thankful that tillithz came up with the original idea. It makes for a very clean factory radio install.
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I verified that Pin 7 does indeed work as the ground. I made the changed to the original post to reflect that.
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I have three coming out of the LC7i
First thing I would do is unplug all the RCAs in your amp except the front inputs, then move the front RCAs to the rear inputs so that the rear speakers are getting the front signal. If the speakers are still quiet it will rule out the LC7i, and its either a speaker wiring issue or an amp issue.
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.
Great point. I am a diehard DIYer so I didn't think of that.

I hope they stand behind their work. I have such a hard time trusting anyone to do that kind of work. Too many people overcharge for work I could probably have done better myself with a little research, and know how and why it was done.

Let us know if they won't help, we will try to get you sorted out.
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Wanted to give you guys an idea of what im looking at.

It looks nice, but I can not believe they did it that way. Would have been so much simpler to interface it with aftermarket harnesses and leave the stock wiring alone.
There is no aftermarket harness for the amp, I've asked several OEM's directly (including scosche).

For the LC7i signal, did they splice into the HU input side to the factory amp? I couldn't tell by the thread convo. If so, might be your problem. They need to pull LC7i signal from the amplified side.

You should be able to tell on your own, looking at the diagram posted on this thread for your amp. Look at the input diagram vs the output diagram, identify the input vs output connectors (by wire colors) on the amp, then see which one they tapped.
There isn't a harness that is marketed as being specifically for the amp, but there are harnesses that work, see first post in this thread.

To the guy that had the shop do this install: I was wondering how it would work after the amp instead of pre-amp, and now we know. Sorry you had to be a guinea pig. Maybe if you show them the beginning of this thread they can get you sorted out.
Every time you introduce amplification you are just adding noise. It COULD be that the amp tweaks the frequencies to sound best in the Tundra's cabin or factory speakers, but Toyota will probably never say.

If I get ambitious enough I'll add color codes to my post for those who just end up cutting the factory wires like you will have to. Toyota uses cryptic 2 character codes for their colors on their diagram unfortunately.

If it were me, I'd have the shop refund install costs and install the damn thing myself. It is literally as easy as (JUST AN EXAMPLE) taking the blue wire, sticking it into the Right Front + input on the LC7i and screwing it down. Every single wire you need is already present in that rats nest of wires. Just take your time. I would never pay anyone a dime to do it.... though I am an obsessive DIYer.
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I added a color code translation to my post at the start of this thread and listed all the wire colors for the factory amp according to the diagram.

Why they would use two white wires on the 145 harness is beyond me, I didn't notice it before. If anyone knows of a difference (stripe, label, etc) between the two factory white wires, let me know so I can add it to my post. I am too lazy to go out and look in my truck at the moment.
Glad I could help. I love tinkering, and if I can pass on some of my research to others, its the best way to "pay it forward."

I wonder if we can get a moderator to sticky this post?
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Let me make sure I understand this correctly before I start pulling everything apart. I have my two Scosche harnesses to modify. According to the diagram and your wire labels, I should take the pins out and rearrange them to how you have it listed above?

I am simply adding a 4 channel amp and nothing else so I'm not sure if I should change my harness to that diagram or not.

Edit: Nevermind, that was a dumb question.
You don't have to rearrange the wires, but it makes it easier to match colors so you aren't fumbling on what wire is what.
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