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2014 Factory Amp Wiring Diagram

171460 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.
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Reactions: 1 : 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.
Wrong size. That's the rear harness for sat. Smaller pins. Its a really old Geo/Isuzu plug I thin .

I don't work at a shop anymore so I can't check.there's a pic of it in my for sale thread where I made one.
white/black stripe is typically ground in a toyota. also look for a wire the same gauge as the 12v battery.
did they pull signal before or after the factory amp?

sounds like they are using the factory amplifiers front output as a signal as it is internally low passed.

they need to pull signal straight from the radio and leave the factory amp out altogether.

that and make sure the jumpers inside the lc7 are set properly.
and theres the problem. you cant pull a signal AFTER the amp. its low passed on the front.
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Probably because a shop doesn't know if a vehicle has hi or low signal coming from the deck to the factory amp... Something that I'm not sure has even been verified with our Tundra. With the system being designed together, I doubt it is hi signal from the HU, so they would be correct that it would not work. If wired correctly, and if the OEM amp is left in place functional, the output of the amp should provide signal to the LC7i and work fine.
not correct. it IS verified that the signal coming from the head unit is a high level powered output that not only powers the dash speakers, it also provides a FULL RANGE signal to the amp which in turn sends a LOW PASS signal to the doors. and this is precisely why its not working for him. LOW IN>LOW OUT. no bueno.

forget the shop. they obviously don't care that they got it wrong, even with proof. i've posted the toyota schematic more than once and it has been reposted quite a few times. its not hard to figure out the wire colors from the diagram when you're looking at the actual harness.
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!!!!!!
last time i talked to them they claim their devices need the higher level input and don't like just a signal. either way i personally don't like audiocontrol equipment, every one we ever used from the lc7 to the deq they all sounded bleh. the only thing of theirs i liked using was the lc2. it was great for sub installs.
So it's all wired correct now and after it was done the manager came and admitted he was wrong and was very sorry.

Does anyone have any pics of their setup on the LC6 or 7? I understand they will all vary but At this point I want to check all their work. I was messing with the outputs of the lc7 and subs sound better with a single positive rca out of the third channel instead of both plugged in and it sounds good.

They have the 2-3 channels summed
does the sub volume go up when you unplug one or other of the sub rca's? try unplugging the left and listen then the right and listen. if the volume gets louder both times then something is out of phase.
Here's the thing. The signal is better from the head unit as it is full range and in touched. The voltage is just lower.

Pulling the signal after the amp can work but the front signal is low passed and the rear is not. If you don't care about the fader it will work. There's no way to use the tundra front in as a front out as it won't be full range.

You are right that the audio control part prefers the output side of an amp, but the tundra radio differs in that the signal between the radio and amp is already amplified and not a typical low signal. A true processor like the bit one or 3sixty is better for this. They sound better and handle the low voltage fine.

I personally don't like audio control products as they don't sound much better than a decent loc.
the signal from the radio is still a better signal as it doesn't need to be reconstructed. also its amplified from the head unit so the audiocontrol warning doesnt apply.
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so the signal coming from the HU is high level (4 - 8 ohm impedance) as oppose to Line level? That's interesting. So the amp under the seat is more of a Low/Hi pass filter/re-amp thing?
the radio powers the front 3 dash speakers. that same full range powered output is used as the input for the amplifier which low passes and amplifies the front doors and powers the rears full range. it is not a typical setup.
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hope it solves any issue you are having. it's the little things that will drive you crazy.
So I replaced my Entune radio with a Pioneer avh-x5700bhs head unit and used the Crux's SWRTY-61N interface to keep the backup camera and steering wheel controls. After install I lost all of my door speakers no sound. The only speakers that work are dash, center and rear door tweeters. I have the factory amp under passengers seat. If I take and hook all the Speaker signal wire's from the amp harness and hook them to the speaker output on the harness would I be able to bypass the amp and just run the speakers off the new head unit?

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

Will this work?
i already told ya. pin 3 sky blue. you dont have the remote tied to it. ill bet if you test it for voltage under the seat it doesnt have it.

no need to go through your ass to get to your elbows friend.
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yep. that's likely someone using the 2 harnesses we posted up, repinning and reselling them.
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So I have a quick question. If the Factory Head unit (Nav Non-JBL) supplies line level input, what is the purpose of a LOC or DSP? Just trying to wrap my head around it because yall have inspired me to upgrade :) I am thinking I should be able to simply use the harnesses I buy and wire it directly into the amp as long as I buy an amp that accepts line level input?
its not line level input from the non-JBL head. its speaker level.
yes thank you. My head is on overload reading all of this post:hyper: and I got my terminology mixed up. So just to make sure I am clear:

Speaker level= High Level
Line Level= Low level

I guess what I was trying to say is that I could just get an amp that has speaker level/high level input.

Would installing a LOC or DSP before the amp increase signal quality or have any other benefits?
I believe the original car head units lessen the bass as you turn up the volume (so car manufacturers can save money by putting less powerful units). The LOC or DSP can fix this problem, which I don't know how they do it, as I delayed this project. But I believe that is the reason to use LOC or DSP. With my 2014 Tundra non-JBL unit, I notice the bass no longer increases or increases very slightly when I reach around vol 20 and higher.

How about buy a converter (speaker level to rca) or an amp with with speaker level input, but one that also has a gain control. Set the gain control to high so that your actual volume output is already very high at vol, say 25 on your head unit. This way, you are still using the normal output from head unit (before the unit alters it and lessens the bass).
this. as the volume goes up, the bass goes up. this stops at a point where the volume will continue up but the bass frequencies attenuate to keep you from damaging the speakers.

unless you are buying high end equipment you can just use the high level inputs and most will be satisfied.

for the bass loss you can use the audiocontrol LC-2. it's about the only thing they make that i like as it is simple and effective.
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That's built into the amp. If you grab signal before the factory amp this doesn't happen. I watched this on an RTA in a Tundra. Bass frequency does not roll off at all before the amp
good to know for the tundra.
My wife has my truck so I can't confirm this. But do I need to order the female or male version of the autoharnesshouse harnesses to connect my DSP on the HU side (removing the factory amp)?
why connect at the head unit and run wires when you can just plug in under the seat?
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