Intermittent ABS light and Brake Light

[S4-RED]

Guys,

Ive only had my baby 2 days and ive just got my first problem

As im driving the obc will display a brake warning, followed by a message saying the there is a fault in the ABS system and the ABS light comes on. I carry on driving and then it goes away!....
I drive like Morgan Freeman in 'Driving Miss Daisy', because I want to look after her, no eratic braking or fast hard corners. Im bafled can you ofyou guys shed some light on this, shes a 98 S.

[ajsl]

Do you know anyone with a VAG-COM ? If so get them to plug it in and look for DTCs.. Someone on here is bound to have one close (I've got one but am in Glasgow).

[Nordschleife]

Would I be right in saying that when you bought the car, you or somebody had a good look at the wheels and suspension, checked the joints for wear, examined the disks and pads?
What possibly happened was that one of the ABS sensors got slightly dislodged and now it is showing an intermittent fault. Its easily done, and, fortunately, easily fixable, check that all your ABS sensors are firtmly seated in place and that the electrical connection is properly attached. Odds are that the fault will be cleared up by this. You should still check everything with a VAG tool and also clear the essors which will be stored in the ECU

R+C

[DavidR]

I had a similar issue caused by a crack on the ABS detection wheel thingy (don't ask me for the part number!) on the rear wheel (the bit between the CV boot and hub). Apparently this is a common failure due to material fatigue, and it wasn't expensive to remedy. Under firm braking it would cause the ABS to activate prematurely also.

[Dippy]

There were a few of us here, myself included, who had spurious ABS warnings over the winter. In my case it happened once only and the brakes are fine since (no DTCs). I put it down to a gremlin...

As the others have suggested, try to check for DTCs.

[Mik]

Hi S4-Red

It could also be a faulty ABS Control Unit. I have had this problem on my 98' S4 which started as intermittent ABS light/DIS ABS Warning as you describe. Its connected to the ECU and if its faulty it may block out your ability to read off the ECU with e.g. VAG.COM. Probably safest to get it to a dealer or AMD to get a proper diagnosis....brakes are pretty important on these cars

Mik

[S4FIFE]

I have the same ABS warning light lit on my 98 SREG S4.Audi dealer checked it says no reading from ABS CONTROLLER/PUMP will need replaced before they can diagnose.Quote of £1100 for new ABS controller !. Any ideas ?, is the ABS controller packing up a common fault ?. Tried to find a second hand controller without success HELP !

Cheers,

Bruce

[SimonS4MTM]

I had the ABS ecu changed under warranty on my old S4

[S4-RED]

Hello All,

The car has been to the Audi Stealers....they say it looks like a fault with the OBC in the dashboard as the brake light and the ABS light come on with no apparent reason...theyve said £588 for a new binacle....Its going back in next week for another 2 days...apparently they want another full day trying to diagnose the problem....and I thought the use of a diagnostic machine was supposed to speed up the fault finding process.

Will let you know...

[S4-RED]

Evenin All....

Problem solved ...it was the ABS ECU that had gone mental.....£900 ...I didnt pay though the dealer I brought the car from sorted it..... I dont want to mention the dealer in the Black County...but Im never going there again....ive seen more smiles on people on death row than at that dealership....

Oh welll at least one thing is fixed ...thanks for you help!