Sounds like you lost an ABS sensor. I beleive the Right Rear sensor is the primary input for speed, so check there first, but it could be any of them. It could be a bad sensor, the wire that runs along the suspension could be damaged, and the its VERY common for the plastic box where the connector is located (behind the plastic wheel well) to be full of dirt and debris which traps moisture and corrodes the wire/connector.
E39 - 1998 540iA Sport (11/97 Production)
E30 - 1989 M3 (44k miles)
1979 Triumph TR7, still have my first car ;-)
E21 - 1980 320i (sold at 130k)
E23 - 1986 735i
I am a BMW Car Club of America member, are you? <a href='http://www.bmwcca.org/' target='_blank'>http://www.bmwcca.org/</a>
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