ABS brain transplant?

[John Dickens]

My ABS faults continuously to fault code 3, front wheel sensor. It resets OK but as soon as it's turned on it faults again. I have checked out the sensor air gap and metered up the sensor resistance at the ABS plug and at the sensor connector itself and it all reads out OK. I suspect the ABS brain has given up.

I have obtained another used ABS unit in good condition.

 

Does anyone know whether I can just swap the electronics from one unit to another or do I have to change the whole ABS unit as one piece?

[Joe Frickin' Friday]

My ABS faults continuously to fault code 3, front wheel sensor. It resets OK but as soon as it's turned on it faults again. I have checked out the sensor air gap and metered up the sensor resistance at the ABS plug and at the sensor connector itself and it all reads out OK. I suspect the ABS brain has given up.

I have obtained another used ABS unit in good condition.

 

Does anyone know whether I can just swap the electronics from one unit to another or do I have to change the whole ABS unit as one piece?

 

I would suggest you simply replace the sensor. I had the exact same problem in '03, but with the rear sensor. Couldn't see a problem with it, resistance was fine, it reset fine, but the fault repeatedly came back as soon as I turned the key on. I replaced the sensor and all was well. Still don't knwo what the problem was, but a new sensor definitely fixed it; things have been fine for the last 50K miles.

[hmeiseles]

A sensor is much cheaper than a new brain.

[Rob L]

Had the same problem with my 98RT. The front sensor was the problem. Dealer replaced it under warranty by using a part off of a new bike in the showroom. BMW of Grand Rapids made a permanent customer that day

[John Dickens]

OK. I'll give that a try first. I assumed that the sensor was fine because it read out OK on the tests. Guess it's another of lifes great mysteries.