In my case I've seen this happen twice:.

Once when my wss worked loose becusse the bolt head snapped off during a bearing job and ever since it was friction fit with some wraps of Teflon. That worked perfectly until summer when the knuckle got larger due to ambient temp. It just needed another wrap or two of Teflon but took me about two weeks to get to it and twice I had to climb under the car add push the sensor back into place.

The other time, enough rust was on the magnetic tip of the sensor I pulled it, cleaned it and it fixed.

I also did break one sensor by slide hammer too close but I think that one showed an actual error.

Hopefully you can find your faulty sensor. The best way is to graph the speed and wait fora glitch. It's very difficult to see in the numeric display unless it's very obviously dead.

In the two times I had malfunction I had the same symptom.

Just about to come to a stop apparently one wheel indicated zero speed as if sliding on ice so abs kicked in to let it roll. After 5-6 jittery stops it gives up trying and disables abs for that drive cycle.

Sound familiar?

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)