S2 Avant ABS ECU Pin Out Diagram

[Tonybolony]

I have seen one of these diagrams recently, I'm sure- but can't find it now!
Can anyone help?
I also need to know if the rear difflock switch is N/O or N/C?

I've had an intermittent ABS warning light fault for months, but light on continuous now,
so I'm in with a chance of sorting it.
Ps its an ABY

Thanx

[driftin jo]

http://www.s2central.net/motronic_pinout_ABY.html

[UrS4boy]

http://www.s2central.net/motronic_pinout_ABY.html

That's for the Motronic Engine ECU not the ABS ECU (but maybe Paul has something for the ABS too?)

[mdz]

http://www.s2central.net/S2_Schematics/C/C31.PDF

[UrS4boy]

Diff lock info if that helps:

http://forums.quattroworld.com/s4s6/msgs/170940.phtml

[UrS4boy]

Found this in a post when I searched on diff lock. Posted by Zoig. Don't know if you can read it, as it is tiny

[ralleyquattro]

There is a small differences between B3 and B4 cars.
B3 have large button, B4 have a smaller one.

On early cars (B3) the ABS turns off/on as soon as the button is pressed/pressed again (button light on/off).
On later cars (B4) the ABS turns off/on only after the diff lock warning lamp lights up/goes out (the green one in the diagram).

Change was probably done because on early cars turning the diff lock button off automatically turns the ABS back on, which not always ment that the diff lock itself was unlocked (vaccum leak, delay in unlocking due to sticking mechanism, rust etc. etc.)

At least this is what I have noticed on Canadian cars, market differences might occur.

[Tonybolony]

Thanks for all your help- I think I've found the fault.
3 of the sensors give a consistent reading, but N/S/Rr is open circuit.

So I'm looking on Amazon/Ebay, and there are dozens of them out there, from under a tenner up to over £100, but a review from a purchaser says that All of the A4 sensors are the same, just the grommets that are different!! (I'm assuming he is not saying that the fronts are the same as rears- You know what I mean!)

Can this be true???

I could well imagine that they are all the same ELECTRICALLY, but physically???

If he is correct- do you think it fairly safe to assume the same scenario for the 80, in which case I may as well buy one to try, and if I can't fit it, it's cost me a tenner!

Any opinions?