My mk3 ABF project!!

[peedman]

Yeh one at a time! Im still waiting on some darn stuff from the us/uk htfu lol.

[Valver.]

Re your PM

The mystery plugs:

Yep, this one is part of the fuel rail loom. If you have the correct rail, this is incorporated with it. If not, let me know and you can have one of mine for cheap.



Yep, radiator fan plug (comes from the fan control relay unit as per the 8v)



Can't remember these ones, but there are no major sensors on that side of the car, so just leave them til last



This should be for the reverse light switch on top of an 02A gearbox. You'll need to run it to your factory 020 switch (the colours should be the same)



By the looks of this, you have the alternator exciter wired wrong - it is a single, blue wire, not a black one

I don't even recall seeing that red plug on anything and my memory is good with this stuff. It's obviously a/c related, though



Nice engine - but make sure you ground your coil externally to something otherwise you'll fry it in no time, though

Throttle body is the wrong way around, too.

**Lastly, and most importantly, though, that is an OBD2 ABF and will have a coded immobiliser, so to make it run, you will need the ignition barrel with transponder, the corresponding key, the Siemens alarm relay setup and the matching 037 906 024BE ECU**

[Valver.]

If you don't have a matching key etc, there is a way around the problem I've come with, but don't want to make it too public (the yanks would have a field day with this, as they have the problem all the time), so PM me if you get stuck

[Golf Loon]

He has the SEAT key and barell and ecu, so all should be well.

That red connector is not used. Just there for the random element.

The ones down by the light on the drivers side are emissions and ac related, not very crucial

Sounds like you are getting closer.

[Golf Loon]

If you don't have a matching key etc, there is a way around the problem I've come with, but don't want to make it too public (the yanks would have a field day with this, as they have the problem all the time), so PM me if you get stuck

Comeon Valver, share the goodness

[Jmac]

That yello connector is for the headlight dim dip resistor if you have one, and yeah Matt is right the single connector is a freebie
Cheers
Jmac

[peedman]

Cheers valver, much appreciated! Yeah ive got everything except the siemens alarm relay setup, is this desperately needed?

The alternator excitor wiring i stole off the 8v so thats why its diff colour plug but im 100% sure its correct. And yeah i would love to grab that plug off u as itll save me some hassle.

[Valver.]

He has the SEAT key and barell and ecu, so all should be well.

That red connector is not used. Just there for the random element.

The ones down by the light on the drivers side are emissions and ac related, not very crucial

Sounds like you are getting closer.

Ah good stuff

The emissions system is on the driver's side on an ABF and is as important as any of the other major sensors: if the evap solenoid isn't connected, the ECU runs in limp mode.

To have a fully functioning OBD2 ABF (apart from the obvious), you need to check these plugs are in:

-The VSS/vehicle speed sensor on top of the box
-Both upper and lower knock sensors
-Crank angle hall sensor
-Cam hall sender
-TPS and throttle open switches
-Single O2 sensor (pre cat only)
-Evaporation solenoid

These will throw codes, but not limp the ECU:

-Coolant temp sensor
-IAT sensor (there is no MAF on Digifant 3)
-Oil low and oil pressure switches

I may have missed something, but will think about it more carefully later

[Valver.]

Cheers valver, much appreciated! Yeah ive got everything except the siemens alarm relay setup, is this desperately needed?

The alternator excitor wiring i stole off the 8v so thats why its diff colour plug but im 100% sure its correct. And yeah i would love to grab that plug off u as itll save me some hassle.

Yes, you need the alarm relay setup. Of that I know 100% as I tested this theory a few weeks ago whilst playing around with rewiring my white Mk1 - I've always been curious what will trip the system, but now have tested everything!

The alarm box also connects to the rear Cupra loom section, so you need a full vehicle loom, ideally, otherwise you have to wire it into the system yourself.

It isn't a difficult swap, but can be if you don't have a whole car.

**Edit: the initially obvious solution is a 'AB' code ECU from an OBD1 car, but with the late loom, you need to switch the injector channels, change the pin for the diagnostic output.... plus find an early ECU and OBD1 throttle bod, so this path is hardly ideal...

[peedman]

Hmmm well this isnt great news at all. Will the car start at all without the alarm relay? What the hell does it look like? I got the full engine loom but not the entire vehicle loom. Megasquirt is looking better now but im not an expert with wiring so it will be a HUGE mission for me.