Aaaaaahhh ABS!!

[iR6 0]

Quick question peoples, car has gone in for it mot today and surprise surprise has failed on an ABS fault!!

 

Diagnostic is saying rear sensor, mechanic is saying that they have replaced sensor (supplied by me) and and has not solved the fault. So they are suspecting the ABS ECU.

 

I always assumed that this was located under the scuttle cover, but they are adamant its part of the pump, and the one under the scuttle cover is the engine ECU?!! I need the part no so i can source a replacement.

 

Can anyone 100% confirm where it is?

 

PS. the garage is pretty reputable and i know them well.

 

Cheers lads

Edited May 8, 2012 by iR6

[Jon_vr6 1]

The abs ecu is behind the lower shelf on the passenger side (inside the car)

[iR6 0]

The abs ecu is behind the lower shelf on the passenger side (inside the car)

 

 

 

Star!!!......cheers fella :)

[Jon_vr6 1]

Star!!!......cheers fella :)

 

 

Quick pic

http://img149.imageshack.us/img149/437/absqc0.jpg

 

Ignore the pedals as this is a US raddo

 

---------- Post added at 5:16 PM ---------- Previous post was at 5:07 PM ----------

 

Also remember that the rear sensors read off the abs cages which are inside the rear disc these can also cause there to still be a fault if they are bent or rusted etc

[owen g60 10]

get it plugged into vagcom and clear the abs codes... mine were stuck in the controller for ages after fixing the actual fault

[floppyman 0]

Get it checked properly...... Im shure its not the ecu

[iR6 0]

Cheers guys, good point on clearing them first. Nothings gonna happen until Tuesday now :)

 

---------- Post added at 8:03 PM ---------- Previous post was at 8:02 PM ----------

 

One point, mot guy said 'if its something serious with the ABS then I'll buy it off ya' now that filled me with confidence!!!!

[floppyman 0]

Cheers guys, good point on clearing them first. Nothings gonna happen until Tuesday now :)

 

---------- Post added at 8:03 PM ---------- Previous post was at 8:02 PM ----------

 

One point, mot guy said 'if its something serious with the ABS then I'll buy it off ya' now that filled me with confidence!!!!

 

Lololol...... Thats just great. The things I seen like that makes me think how come people trust theyre cars to other people

[NewbridgeJob 0]

My ABS is fine but the light is always on. I just unplugged the switch for the MOT to save the hassle

[guildmage 11]

My ABS is fine but the light is always on. I just unplugged the switch for the MOT to save the hassle

 

But they will check surely for that? As it has to go ON with ignition and then OFF after few secs.

[beastie4126 0]

But they will check surely for that? As it has to go ON with ignition and then OFF after few secs.

 

New MOT rules this year mean that they should be checking for this now. If it doesn't light up and then go off will result in a fail.

[Dox 23]

I'd be looking at the condition of the reluctor ring on the back of the brake disc where the sensor picks up on before suspecting the ecu

[krishen 2]

New MOT rules this year mean that they should be checking for this now. If it doesn't light up and then go off will result in a fail.

 

Depends how diligent they are with checking everything.

[Dox 23]

That's what they get paid for.

 

VOSA reps park down the street and observe the tests taking place via laptops as well as sending in cars with known faults to catch out MOT stations. My tester wouldn't miss a non functioning light and if the light is on the dash the ABS is not working.

[iR6 0]

Well they said that the bolt on the rear to take the sensor off is rounded off and they would need to drop the axel to change them.

So to save time they plugged the new sensor in tried it that way, not sure how that would work??

 

---------- Post added at 5:33 PM ---------- Previous post was at 5:32 PM ----------

 

I didn't think dropping the axel would increase access to the sensor?!

[floppyman 0]

Well they said that the bolt on the rear to take the sensor off is rounded off and they would need to drop the axel to change them.

So to save time they plugged the new sensor in tried it that way, not sure how that would work??

 

---------- Post added at 5:33 PM ---------- Previous post was at 5:32 PM ----------

 

I didn't think dropping the axel would increase access to the sensor?!

 

Did the guy asked you again if you wantes to sell it? Lol. Get some one else to do it fornyou

[KIPVW 0]

Irwin bolt gripper alert, and then tell the Garage they are useless and take it elsewhere.

 

Take the beam off :lol: i drilled one out in 20 mins start to finish on the drive. I certainly wouldn't trust them if they are giving you that story. Grrrr!

[K Simmonds 10]

Agree. There is absolutely no need to drop the rear axle to change an ABS sensor. Mole grips, a leaver and swearing are all you need.

Edited April 7, 2012 by K Simmonds

[Stonejag 10]

The rear ABS cages are very cheap to replace (mine were around £8 a side) and simply clipped onto the brake disks so easy to change. Could consider changing the wheel bearings while you have them off.

 

Handy trick for MOTs is to force the ABS light out by holding the brake pedal as you turn on the ignition - should get a clunk from the pump and go out. If it won't go out (usually clunks immediately rather than after a short pause as the light goes out) then it will clear if you go for a drive - half an hour normally sorts mine. The light will stay off until an error is next detected (usually incongruous wheel speed reading caused by a duff rear sensor) so even with a short test drive it won't betray you! If the light comes on immediately every time and won't clear then start to suspect pump or ECU, if it stays off for a while then it's more likely a sensor.

 

Good luck with the test!

 

Stone

[seanl82 23]

The fault wouldn't clear by just plugging a new sensor in either! The sensor needs a signal from the reluctor, and it will reset once 15mph is reached iirc, or reset via diagnostics port.

 

 

ALSO, to get the one out of the front on my Golf3, I had to smash the sensor up. Its just a piece of plastic with a load of copper wire inside for christ sake! Why take the beam off!!!!

 

Here is a how to I made on GolfGTIforum for the mk3, my be the same for Corrado too.

 

http://www.golfgtiforum.co.uk/index.php?topic=204972.0

Edited April 8, 2012 by seanl82

[floppyman 0]

The fault wouldn't clear by just plugging a new sensor in either! The sensor needs a signal from the reluctor, and it will reset once 15mph is reached iirc, or reset via diagnostics port.

 

+1 .... Its all sounding a dodgy garage.

[iR6 0]

Well went to collect the car today, and the guy explained what he thought was wrong-

 

They had an error code relating to the o/s/r abs sensor, so with the car on the ramp, they plugged in a new sensor. Then scanned the ecu again, fault was then n/s/r sensor (o/s/r fault had apparently now cleared). Plugged another new sensor in, scanned, fault was now o/s/front sensor (n/s/r now cleared)!!

 

I didnt supply a new front sensor as this had never shown up with previous scans.

 

So the mechanic has spoken to his auto electrician who has advised a faulty ecu. Though none of the above can be 100% apparently as these things are hit an miss!!

 

Anyway i've not got a problem spending cash on my Corrado, though dont want to be chasing something that does not need doing. So I think im going to replace both rear sensors properly with new cages (already have the parts) then clear codes take for a run. And see what codes are then thrown up.

 

Once sorted i'll update this thread for future searches (though i think every ABS problem has been discussed already:) )

[Roger Blassberg 0]

I have a spare ABS ECU with traction control (EDS) from a Passat B4 VR6. I think its the same part as the Corrado, if it turns out that you need it.

 

Let me know.

 

Best wishes

 

RB

[iR6 0]

I have a spare ABS ECU with traction control (EDS) from a Passat B4 VR6. I think its the same part as the Corrado, if it turns out that you need it.

 

Let me know.

 

Best wishes

 

RB

 

Thats great to know cheers Roger. I'll replace the sensors first and see what happens. Thanks again

[iR6 0]

Right folks really appreciate some guidance with my persistant abs problem that is keeping my C well and truely grounded!

 

As mentioned in earlier post in this thread the corrado failed its mot on the abs light being on.

 

Vag comm said rear sensors, garage said faulty abs ecu.

 

Anyway after lots of uncertainty i took the car out of the garage and started replacing the parts needed myself.

 

First up os/r sensor, changed with new abs rings. Next ns/r sensor, changed with new abs ring. Fault codes cleared. Run round block, new fault, front right sensor.

 

No more rear faults showing, just the new front right fault. So i do what i can, clean conections and the sensor and ring (didnt have a new sensor at that time). Fault still shows.

 

I then started to think that what the garage said maybe true (abs ecu) so i take a look at that, conections all good, no oxidisation, or water ingress. still clean contacts etc to be sure.

 

At the time i really wanted to get the car done in time for the Stanford hall show. So i got hold of a replacement abs ecu and two new front sensors. ECU came first so i plugged it in, cleared faults then ran car with it. still front right sensor fault :( So i put my original ECU back in.

 

Now this evening i have fitted the new front right sensor, cleared code, driven (1 mile). And the friggin light still does not go off!!! Fault of 'front right sensor' still shows!!

 

Am i correct in thinking the front right sensor does mean the drivers side. Not right as in looking at the car?

 

At no point during any of the above has the ABS light gone off. It flickers very briefly when i start up (guess thats the diagnostic check) There is no click of the pedal, like previous raddos either?

 

Can anyone shed any light on this? Was really hoping to have it ready for the Brooklands meet and this is the only problem i need to sort for the mot.

 

Cheers for looking peeps