ABS is completely dead and need MOT - FIXED?

[dinkus 10]

My ABS is completely dead, so no light comes on at ignition time, so it's failed the MOT.

 

I need to get it fixed and it sounds like the ABS isn't getting any juice at all and I've tested it and it doesn't work (found a quiet road, jabbed the brakes, wheels locked up with no ABS judder).

 

Fuse 4 is apparently the ABS fuse in the main fuse panel and looks good, but so do all the other fuses in there.

The panel behind the glove box has: 2 fuses which are also good and 3 relays, which are all corrosion free, but don't know for sure if they work (how do I test them?).

I've also got a spare ABS ECU, but swapping that didn't make any difference.

 

So now I'm outta ideas... anybody got any suggestions?

 

Are there any more fuses or relays I can check? Or is it chase the bastid wire time and see if there's anything wrong... hmm, I've had the fusebox a couple of times, so maybe the connection on the back of there has come loose...

[steve_16v 0]

Tried VAGCOM?

[CrazyDave 0]

I'll have a flick through the Bentley and see what I can find, but VAG-COM would be my first port of call also?

 

If you can get communication with the ABS module then it proves its got power and isn't dead, then the fault codes should tell you the rest.

[dinkus 10]

I don't have VAG-COM, but as the light doesn't come on at all (checked the bulb too, should have said that in the first post) and that swapping the ECU with a known-good one hasn't solved it, I suspect the thing's getting no juice, thus VAG-COM won't help.

 

It's all a lot of assumptions tho...

[vwdeviant 0]

Dinkus see if you can get an Auto-electrician to have a look they're pretty good at diagnosing these things...

 

Will be able to see if there's continuity between fusebox and ecu.. etc..

[dinkus 10]

Yeah, if only I could find my multimeter.

 

Might see if I can pilfer one from work tomorrow evening and buzz it out.

[CrazyDave 0]

OK, a few things to check.

 

The ABS is feed from the X contact relay (number 4) or load reduction relay. Check that it switching when you put the ignition on, although you'll have other stuff that doesn't work if thats faulty (like wipers, heat rear screen etc so I guess thats not it).

 

You should have 12v on pin 53 and 35 of the ABS ECU with the ignition on, this also switches the ABS Relay on (J102 is the only reference I have for this?). The feed for this is again off the X load reduction relay and it also puts power to the ABS flow return pump. So nothing will work without it.

 

Fuses to check S16, S21, S53, S54.

 

Just a start, but that's the only stuff that prevents powering of the ABS controller?

 

Give it a go.

[dinkus 10]

Ah cool thanks for that - gives me a list of things to check out tomorrow.

 

I shall let you know how I get on :)

 

 

Edit: Err, do you know what it means by S16 etc? There are 22 fuses in the panel and number 4 is the one listed for ABS. Is there a cunning code I need to translate to work out which fuses it is?

[CrazyDave 0]

Well it's a Bently thingy, its just 16 really, but the trouble is that it keeps moving around from year to year. So on a 94 model year it says it on 21 & 22.

 

The higher fuse numbers are mounted elsewhere on the car.

 

The ECU pin numbers I've given you are for a Teves 02 (it has three rows of pins in the plug). The old one has only 2 rows. So again have a look and see what you find.

 

Well that's my bedtime reading out of the way, am I dedicated to the Corrado or what!

[dinkus 10]

Ahh ok. Will have a look tomorrow then.

 

Thanks for looking it all up tho :)

[12 DEG BEN 0]

Nuts dinkus. Got similar abs tom foolery going on in mine and my mot looms. Was hoping you had vagcom at yours as you sound like a technical bloke. Spend time visiting Robbie next door to you but never bump into you. Must work way too hard

[dinkus 10]

Oh so it's you he was talking about! :lol:

 

I'm usually around after 5 tho, so knock on the door next time you're about.

 

I have been meaning to get VAG-COM for a while, but it's a lotta pennies and I have plans for the C over the summer that would make it redundant... ;)

[StuartFZR400 0]

Plans?

 

As for not having a multimeter, can't you just use a fuse that you know is working from another circuit?

 

Did cheesewire get rid of his VAGCOM? Alternatively can't you search the VAGCOM THREAD for people who do own it??? ----- you say that it wont work, but atleast you can rule it out if it doesnt work.

 

3rdly , if its not getting juice, how does it normally get juice, how can it not get the juice and is there a way of bodging for 2 minutes to see if it is that item (wire etc)?

[dinkus 10]

Plans?

 

As for not having a multimeter, can't you just use a fuse that you know is working from another circuit?

 

Did cheesewire get rid of his VAGCOM? Alternatively can't you search the VAGCOM THREAD for people who do own it??? ----- you say that it wont work, but atleast you can rule it out if it doesnt work.

 

3rdly , if its not getting juice, how does it normally get juice, how can it not get the juice and is there a way of bodging for 2 minutes to see if it is that item (wire etc)?

 

I shall say nothing of the plans, because they are just that. Will obviously post up here if/when it turns into an actual project :).

 

The fuses are all definitely good - you can see the metal running through them is in one piece.

 

Cheesewire may still have his VAG-COM, but he's now a good 4hr drive away and I'm not sure who has a 2x2 connector round these parts.

[PhillT 0]

I'm spitting distance away but don't yet have a 2x2 connector yet :( so not much help..... which makes this post pretty pointless

 

 

But If I can get some sort of wiring diagram for the 16pin - 2x2 cable I could probably get something made up in no time at all!

[coolrado 0]

The fuses are all definitely good - you can see the metal running through them is in one piece.

 

Cheesewire may still have his VAG-COM, but he's now a good 4hr drive away and I'm not sure who has a 2x2 connector round these parts.

 

Just because they look intact it doesnt mean they are, i have seen a few faults on cars that after hours and hours of wire tracing have turned out to be a dodgy fuse that looked ok at first, some fuses are one single piece of metal which have been pressed into shape, but some are made up of the two blade sections and a seperate piece for the fuse which are pressed or crimped together and those are the ones that can go OC without looking any different.

 

it really is worth checking them with a meter.

[dinkus 10]

Ah good to know. I shall mostly be doing that this evening then. And re-greasing my spoiler mech (ooh err).

[dinkus 10]

So I fixed it, but not because I was trying to.

 

My spoiler has been jamming and popping fuses, so I had removed the fuse for it and left it be. Anyway, this evening I took the mech out, stripped it, re-greased it and put a new fuse in. Sadly it didn't solve the spoiler problem but the ABS light now comes on! :lol:

 

It would appear that the spoiler, sunroof and ABS are all powered off the same fuse...

[Stan 24v 0]

:lol: Nice one Dom

[CrazyDave 0]

Sorted then! Cool. But now I'm going to have to read the book again to see why I couldn't find that? 8)

[dinkus 10]

I'm happy it was an easy fix, but now I'm annoyed that my hours of swearing at the stupid bastid spoiler mech were mostly in vain :(

[StuartFZR400 0]

I'm happy it was an easy fix, but now I'm annoyed that my hours of swearing at the stupid bastid spoiler mech were mostly in vain :(

 

You've stripped the spoiler mech' down then Dom? ... as per the spoiler thread. Good luck, looks like a b**** of a job !!

[coolrado 0]

if your motor is dead i have a spare you could have for nowt.

[dinkus 10]

You've stripped the spoiler mech' down then Dom? ... as per the spoiler thread. Good luck, looks like a b**** of a job !!

 

Yup, wasn't particularly fun...

 

if your motor is dead i have a spare you could have for nowt.

 

Sadly, I think it's the actual mech that's jamming - it goes up ok, but you can hear the motor straining when it tries to lower it again. Ho hum, might need to find another mech from somewhere...

[coolrado 0]

i do also have the mech as well, the only problem with it is the bits at either end where the supports for the spoiler poke through are cracked where someone has over tightened them, the middle section with the motor on and tubes and cables are fine though, so all you would need to do is swap the ends over.