windwalker

I replaced the front two axles on my 2001 B5 1.8t and I accidently rotated the abs sensor. When I was finished, the ABS sensor would activate at really low speeds but would not cause the ABS light to illuminate. After reading some articles on this, I jacked the car up and sprayed brake cleaner over the sensors, pushed them compeltely in, and rotated them so that the harness was facing 12 o'clock. PROBLEM FIXED.

Most of the time it is just a mis-seated sensor that needs to be rotated and pushed in. If this fails, try reseating the axles. The tone ring might not be seated properly. A simple error when trying to swing the control arm around and get the spindle through the hub assembly. Let me know if this helps. I will post my MAF sensor fixes soon as well (rewiring harness, and common "unknown" black wire for later B5's fix).

2001 Audi B5, 1.8t, GAIC, RS4 Front Bumber

kaneelschep

Sorry to resurect the dead But I had the same problem on my fwd tdi 2001. And google brought me here. Thought I bring it to a closure for the next person to find it..

I swapped the rear wheelbearings yesterday and (stupidly) thought to clean the old rusty abs rings. probably pushed to hard with my wirebrush.
So after I put it all back together I got the same abs cutin at slow speeds.
Took the caliper and caliperbracket back of again today (5 minutes work on the driveway) and shone a light on the abs sensor and ring while turning the wheel.
There was a clear wobble in the ring. I put a screwdriver behind it at the wobble. Bent it back towards the sensor a tiny bit. And the abs cutin is gone.
Besides that. the ring costs 8 euro and is really easy to replace..
If I would have known this ring would be like this before, I would have just bought them along with the new bearings anyway.
But I am new to the car. Only owned her since last week.
Discs are quite new too.. So Why the previous owner didnt just buy new bearings and rings with the discs....? Ahwell..

4driver4 gave all the answers. Problem lays in the distance between ring and sensor.
And yes. Disconnecting abs is dangerous and never an option. I had it disabled by previous owner on my 82 mercedes 500sec. And it was a death trap in the rain. First thing I fixed.
Cars that come with it, really need it!!! Dont be lazy. Fix it!