The 1.8T Wiring Harness Explained

[BEASTINB6A4]

The 3 pin connector is for the intercooler, and the single pin connector is the signal wire for starter, connects to alt,bat,starter harness

[Jusa101]

That first post really needs some update concerning those "(possibly wrong)" and "????" parts. If someone who has access to Elsa or other VAG dealer programs, please add the info here. Those pictures are useless because there are some major differences where the connectors are located in different engines but wire colors and combinations are accurate enough to figure out which connector is which.

[B6A4Dave]

I'm going to necrobump this and see if anyone... psssttt Cliiiiiint!.... Has the factory pin out of the ECU harness..

Trying to compare the B6 Harness to another 1.8T powered car..

[maxpower2014]

hi guys i know its old thread

but i need help i am on the same issue looking for the ecu harnesses pin out under the ecu water box

the harnesses red black brown and yellow so any wiring diagram guys

[vtraudt]

Is it possible to splice the Hall sensors (engine speed/crank, cam shaft position; maybe knock)?
For example cut and replace connector on the harness side?

[Italy1]

Gentleman, I hope I'm in the right place. I was replacing the wire harness plug that was cracked and would not stay connected to the throttle body and it completely fell to pieces from old age. Would it be possible for someone to send me a few pics that would identify the position of the wires in the plug end so that I can correctly install them in the new plug? I appreciate all your help. Thanks

[Nollywood]

Gentleman, I hope I'm in the right place. I was replacing the wire harness plug that was cracked and would not stay connected to the throttle body and it completely fell to pieces from old age. Would it be possible for someone to send me a few pics that would identify the position of the wires in the plug end so that I can correctly install them in the new plug? I appreciate all your help. Thanks

I'm sure someone could help.

You don't state your year, model or engine size, so it's going to be kind of hard...

[vtraudt]

You don't state your year, model or engine size, so it's going to be kind of hard...

I have an AEB harness here if that is what you have.
Wiring diagram will show the colors and pins, too.
State year and/or engine code.

[Italy1]

Thank you for help guys. It's a 2000 A4 1.8t quattro, engine code ATW. I'm sure your time is valuable and I very much appreciate your assistance. Happy New Year gentlemen!!!

[Italy1]

Clint, I'm new here and came across your wire harness write up. Impressive and great information. I have problem with my daughters 2000 A4 1.8 ATW that I believe you could help me with if you don't mind. I was changing out the plug end that would not stay connected to the throttle body. As I was changing out the plug end with a new one it completely fell to pieces from old age I assume. Could you please take a couple pics of the throttle body plug end that I could use to repin the wires correctly in order as they should be in the new plug? Or even a description of what they should be would work the same. I greatly appreciate your time. Thank you

[linust]

Any chance you still have the pics? Updated links? Thanks!

[AudiA4_20T]

yeah, sorry I'll get around to this.

[3bg4mopassat]

Can you please post the 2004 vw passat awm wiring?

[G.AUDI]

^ Second this

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[AudiA4_20T]

^ Second this

Sent from my ONEPLUS A3000 using Tapatalk

haha I happen to now have an AWM Passat.... I don't feel like taking the whole harness off though. What do you need?

[Tee813]

I recently bought a B6 A4 Quattro and whoever worked on it before me cut wires and randomly added some grounds. Does anybody know where to find schematics that show which are signal wires, hot wires, and grounds?

[neo0211]

Does anyone know which side of the 2004 1.8T to connect to the speed signal line to sense the signal?
Which line is it?

[AudiA4_20T]

Does anyone know which side of the 2004 1.8T to connect to the speed signal line to sense the signal?
Which line is it?

Not sure what you're asking. I believe speed comes from the front driver's side ABS wheel speed sensor

[neo0211]

Oh~~ I am sorry.
Should it be said that the RPM signal line of the dashboard is which?
I want to pick up the RPM signal.

[AudiA4_20T]

Oh~~ I am sorry.
Should it be said that the RPM signal line of the dashboard is which?
I want to pick up the RPM signal.

There is none on the B6, it's done through CAN

[1.8taco]

You know the Bentley manual has all of this, right?

Let me know if you need any diagrams and I'll post them up.

Hey how's it going man by chance can u post or send me the b5 a4 atw ignition coil diagram I'm redoing my coil connectors cuz they're fried like carlos santana at woodstock I'd really appreciate it if u can help me out thanks

[sgudino]

This is the best write-up for most wires I have seen on this forum. Do you kow where the cam position sensor leads to? I need to cut into that wire as i beleive a short is happening and i can not see the phase 1 intake bank 1.

[sgudino]

Does anyone know what part I should order? ignition connector
I purchased an ebay item and the part number is: 1J0 973 724, for a 2002 Audi A4 B6, 1.8T FWD
When I tried to install the ignition wires they would not go all the way in, I was about 1/4 inch from the end.
What is the part number for this car.

[Raudib6]

Hey boss i know this is a old thread but I'm wondering if you would know where the red and blue wire on the b6 1.8T harness on the T10a connector went to? I'm not getting power to my injectors and not sure why. traced it back to the brown connector (bcuz pulled harness) if you know where it goes to i would appreciate it so much!!! Also this thread has helped me rebuild my whole harness so i wanna thank u for building this thread. Its perfect. Jus lost on the one wire now. Thank you in advance to anyone that can help!

[sgudino]

Hey boss i know this is a old thread but I'm wondering if you would know where the red and blue wire on the b6 1.8T harness on the T10a connector went to? I'm not getting power to my injectors and not sure why. traced it back to the brown connector (bcuz pulled harness) if you know where it goes to i would appreciate it so much!!! Also this thread has helped me rebuild my whole harness so i wanna thank u for building this thread. Its perfect. Jus lost on the one wire now. Thank you in advance to anyone that can help!

sorry for the delay i was outside working on my wifes car. do you mean the brown wire on the connector ignition 4 wire connector on the ignition coil ? i have never gone passed into the ECU, although i was close a few times.
Let me know, more about the issue and i will try to help you. as there are plenty of schematics out there.

[sgudino]

refer to the link below
https://www.audizine.com/forum/showt...ness-Explained

[r77augh]

I have the wiring diagrams for my 2000 a4 1.8t (ATW) but cant figure out where the 3 duplicate colored wires (green/yellow stripe) pin out to in the ECM. The wiring diagrams I have don't even have the green/yellow wires going to the sensors but the actual sensors have them wires going to them... MAF sensor (G70), EVAP (N80) and wastegate bypass regulator valve (N75). when my scanner is hooked to the car and up to temp, the IAT reads over 200 deg, didnt check the rest.. I really dont understand the diagrams but i hope they uploaded here so that someone can help me out... thanks

[Raudib6]

So I’m actually looking where the T10a 10-Pin Connector, brown pin 1 from the injectors on the b6 platform. U have a question mark on the post and that literally the only one I need to know where it goes to. It’s a red and blue wire from the injectors that goes to that connector in the plenum chamber or (ecu box) if u know where it goes to on the b6 chassis that would b awesome. The Bentley only tells me so much and I can’t seem to get any type of continuity test to work in my favor trying to find where it goes

- - - Updated - - -

sorry for the delay i was outside working on my wifes car. do you mean the brown wire on the connector ignition 4 wire connector on the ignition coil ? i have never gone passed into the ECU, although i was close a few times.
Let me know, more about the issue and i will try to help you. as there are plenty of schematics out there.

So I’m actually looking where the T10a 10-Pin Connector, brown pin 1 from the injectors on the b6 platform. U have a question mark on the post and that literally the only one I need to know where it goes to. It’s a red and blue wire from the injectors that goes to that connector in the plenum chamber or (ecu box) if u know where it goes to on the b6 chassis that would b awesome. The Bentley only tells me so much and I can’t seem to get any type of continuity test to work in my favor trying to find where it goes

[Raudib6]

I have the wiring diagrams for my 2000 a4 1.8t (ATW) but cant figure out where the 3 duplicate colored wires (green/yellow stripe) pin out to in the ECM. The wiring diagrams I have don't even have the green/yellow wires going to the sensors but the actual sensors have them wires going to them... MAF sensor (G70), EVAP (N80) and wastegate bypass regulator valve (N75). when my scanner is hooked to the car and up to temp, the IAT reads over 200 deg, didnt check the rest.. I really dont understand the diagrams but i hope they uploaded here so that someone can help me out... thanks

I would take a multi meter and do continuity test on it to see which plug it goes too🤘🏻