Tdi Wiring Loom Connections

[T3Aljezur]

HI all
Having issues wiring up my 1.9 ahu tdi conversion
I have the complete loom from the tdi installed where it came from on the engine
I know and understand what wires are what on the t3
what I can't figure is the connections from one to another
I know there are guys on here that can make up a new loom but to be honest I can't afford it
Does anyone have the info please, actually pretty please, and a case of beer for anyone if you're ever down this way
Thanks all
Dic

[ewenmaclean]

Hello,

I used this diagram to help me understand the tdi wiring:

http://www.haywood-sullivan.com/vanagon ... _LONG4.pdf

the "interface" with the T3 wiring is something you have to figure out really - syncroandy does a great loom for this but if you're short on cash then you can figure out what you need from the original wiring from that diagram. The majoirity of your tdi loom will be connected to sensor and the ECU - what you need is to get an ignition feed and battery feed for the 109 relay (J317 on that diagram), use the glow plug light wire and connect to the ECU as well as the glow plug signal from the ECU (the ECU controls the glow plug time). If you're not worried about cruise control for now then earth the brake and clutch switch connections and do the same for the brake light failure signal (pin 44).

There's no "plug and play" really if you want to do it yourself I'm afraid.

Ewen

[T3Aljezur]

excellent thanks for the info Ewen
Thats gonna be a big help
I have however a small issue in that my ecu is from a 1998 Audi A4 and it's not a 68? pin unit
It is actually 2 seperate connections. I'll get the part number and pic later
Many thanks again
Dic

[ewenmaclean]

Hello Dic,

ah sorry - you've probably got an 80 pin ECU then (018 code at end?). The principles are pretty much the same but the pin numbers will be different - in my experience the vag wire colouring tends to be pretty consistent (I stand to be corrected!) so that should help a bit with understanding your loom.

One thing to be aware of is that the glow plug wire and the wire to activate the relay (that's blue/green (pin 48 on diagram) and yellow/blue (pin 50)) are the ECU provding an earth - not a 12V signal. I found that the ignition wire to the relay in the original setup had voltage drop coming all the way from the front, so I used a relay for the 50 pin. Also - you *might* find in your set up that the brake and clutch switch signals expect +12v not earth when closed - I'm not sure about this but syncroandy wrote something about it here:

https://club8090.co.uk/forum/viewtopic.php?f=12&t=106215" onclick="window.open(this.href);return false;

the van should run ignoring these switches though - it will just log annoying error codes.

Ewen

[T3Aljezur]

Hi Ewen
Yep code ends in 018 and I think counting it is an 80 pin.
Lost count..........
Gathering info still. Have a guy from the T4 forum who says he can help, I just need to supply info
I would love to be able at the end of this be able to do an idiots guide to the junction between old and new that would work for everyone
Will have to see how we go
Thanks again and keep the info coming. Not reched overload and internal implosion yet

[T3Aljezur]

ok, more work done and more info coming
I am desperately trying to find a wiring guide for an 80 pin ecu
code is 038 906 018 r and it's the pinout wiring I need
Cannot seem to find one anywhere.
Anyone got anything? Pretty please??

[ewenmaclean]

Hello,

my computer with elsa on has died I'm afraid, but if you're lucky (it seems to be offline at the moment) you can sometimes find what you need here:

http://elsaweb.spaghetticoder.org/nav/EN/VW/

From what I can tell (very quick look at a different 80 pin revision number) pin 45 is for K-line (and probably immo2), earth is pin 1 and 22, 109 relay power feed goes to 2 and 28, and ignition switched live goes to pin 47. I'm guessing that this is probably the same for the same part number with a different suffix but I may be wrong so I'd try and verify that first. The other connectors and wires along with the other diagram and some detective work should be enough to figure out what they are.

Ewen

[T3Aljezur]

thanks Ewen
Been having a nose for the past 30 mins and have found the pinout for the instrument cluster, which will be useful as it has the immo in it
I am unable to find the pinout for the ecu. Am I being thick ?
Thanks again
Dic

[ewenmaclean]

Hi Dic,

no - it's a bit of a pain - if you go to "checking components and functions" of the direct injection system then it will tell you what pins to what by telling you the pin numbers for the related sensors. It's pretty painful though - I think a Bentley for the car it came from might be a better bet. Here for example (just an example - I don't know what car your engine came from)

http://elsaweb.spaghetticoder.org/doc/V ... 31587187/3

it tells you which pins of the ECU connect to which pins of which sender. Like I say - it's a pretty time-consuming process I'm afraid.

Ewen

[ewenmaclean]

Hello again,

sorry I can't find the current flow diagrams there either. I'll see if I can find one later if I can resurrect my computer..

[syncroandy]

Hi Dic, you have a PM.

Andy

[T3Aljezur]

thanks Andy
Just repleid

[T3Aljezur]

well, after much help (thanks you know who you are), and many hours making a loom, I have succesfully fitted an A4 potted loom into my doka and it works.
I have yet to run it properly but it starts and ticks over loverly
The dash from the audi (still have it cos of immobiliser) beeps very loudly. I'll have to see what I can do. Maybe turn up the radio
Will run vcds when its all finished
Installed all relevant electrics and A4 dash into the tool locker. Nice and dry and tidy