abs light no codes...

[jbh]

this has happened a few times lately.
the abs light will come on 5 minutes into a journey ( ive noticed it mainly happens if you hit a rough patch on the road ) turn the ignition off then on and it will stay off for the rest of the journey or even a few days.
I got chance today to scan it no codes come back..

tonight the explanation mark come up on the dash.. it came on a few times but went back out. the brake fluid level is sitting on the max so I know its not that. could this be linked?

any ideas?
is this the dreaded abs fault starting to appear?

 

[aragorn]

Is the ABS light on as well?

If not its probably a bad brake fluid sensor, unplug the reservoir and see if it goes away.

Edit:

Hmm, ABS light with no (!) means there should be codes.

ABS light and (!) and no comms with the ABS unit means its probably failing.


Are you sure you were getting no codes, rather than no comms?

 

[jbh]

the explanation light come on its own tonight but previously its been the abs light and the explanation mark that's come on.
the explanation mark came on and off tonight with movement but I checked the fluid level and it was fine.

we've not had the abs light on for a few days ( since I changed the wheels strangely )
but as I say I got chance to scan it tonight and there was no codes logged for the abs

 

[aragorn]

did you use VCDS or something else?

 

[jbh]

going to put vcds on it tomorrow just used my scanner tonight which does do vag stuff its never failed me before.

the scanner is a specific vag memoscan one.

 

[S4_dan]

You will need to scan the ABS module through VCDS. Most aftermarket scanners only do the main the ECU.

 

[Bradderz_1988]

I think he has the same scanner i have the u280 iirc and they pick up a code in engine, abs, srs and A/T.

Have you done any work on the car ie cv joints, bearings etc ??

If so, It may well be a badly positioned sensor or cracked reluctor ring.

 

[aragorn]

I've had bad sensors, unplugged sensors and cracked reluctors on my quattro at various points, and its never generated the big beepy (!) warning. Just brings the ABS light on.

 

[Bradderz_1988]

Is there a difference to how it flags the light between immo2 and 3 clocks as im sure when my abs sensor wasnt sat close enough it threw the big (!) on ??

 

[aragorn]

Perhaps? But my track car is PFL and i'm pretty sure it just brings on the light too.

 

[jbh]

wouldnt it log a code though? this might be worth a check as I know the abs sensor on the rear is pretty free in the hole.

 

[aragorn]

yeh it defo logged a code when my light has come on.

 

[jbh]

vcds has no codes logged either..

 

[jbh]

I think he has the same scanner i have the u280 iirc and they pick up a code in engine, abs, srs and A/T.

mines is the U585 Super Memo Scanner it does read the engine, abs, srs, A/T, and loads more.. it also does the instruments aswell which I scanned.. nothing