Infuriating ABS problem. 2.6 Avant 2 wheel drive

[New Zealand Audi Loner]

Hi

Appealing to all you tech wizards for some devine inspiration please. ABS activated at low speed braking, always on one front wheel. Warning light comes on after a few miles. VCDS tells me that it is error code 00597 - Wheel speed deviation. OK. but which wheels?. Wheel bearings in rear hubs have been replaced and are adjusted correctly. Fronts seem OK.I've re seated both sensors and I'm on the verge of replacing one............. If I can find which one is acting up!.

What should I try next please?

Thanks in anticipation.

John P.

 

[Steve Q]

Hello John, welcome to the forum :)

sorry to hear your having issues. I think you might have to do trial and error on this one. The other thing it could be is the abs wiring instead of the sensors. 

Hopefully one of them more experienced members will be able to help you further. 

Cheers

steve 

[Magnet]

Hello John,

I could be barking up wrong trees here, or just barking! Could this issue few more to do with the condition (e.g. rusty?) sensor rings on the wheels, rather than the sensor/s themselves? Might be worth inspecting each of these.

Kind regards,

Gareth.

[New Zealand Audi Loner]

Thanks Gareth, you were right on the money there. About 10 mins after posting the problem I want back to the old girl and pulled all the sensors hoping for something obvious. On the right rear were 2 rusty bits of scale stuck to the magnet. I removed them and hey presto, everything works like a dream again.

What I don't get though is why this was making the right front brake cycle through the anti lock 'stutter' at low speed. Just the right, and only the front. I can only guess that with one (undriven) rear wheel showing as moving slower than the other, the ECU assumed that the car was in some sort of spinning slide and this is the best way to correct. Maybe the forum wizards could comment on that?

Thanks

[Magnet]

Hello John,

Well done you. Reasons why? Now don't get too enquiring of us on here!! The logic of Audi is not ours to question.

Might be something to do with northern hemisphere built cars being used in the southern H!

We hear that the water circulates down the plug hole in the opposite rotation with you - so who knows. 

Trust all is trouble free for you from here in.

Kind regards,

Gareth.