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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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Thank you awesome write up!
Can we request this as a sticky?
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.
tillithz, I am using the exact same equipment as you except I don't have a sub. Would it be helpful to me to have your setting? I have never adjusted an amp or LOC before.
So i got everything installed the other day by a local audio shop and my rear door speakers are so faint and muffled i can barley hear them, however there is audio coming out of them. The fronts and woofers sound great! I asked them about this and he didn't really respond with a great answer so im coming to you guys for some possible ideas. My setup is as follows (short and sweet).

Alpine 3 way 6x9 fronts
Alpine 2 way 6.5 in the rear
JL 5 channel amp
fox acoustics w/ two JL subs.

I did see they summed the third channel as the "light" is on.

I haven't checked the wiring but figured it might be ok since there is still sound coming from the speakers, but you literally have to put your ear to the speaker to hear it. Would you guys have any ideas as to why it might do this?
I installed mine the other day too, same issue, no solution unfortunately.
Did you run one set of RCA's or 2?
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