Had an interesting issue with this on the Alpina, airbag light came on and the code showed ABS module door B pillar low voltage. And it wouldn't reset. I took the car to Simpson Motorsport (local BMW specalist) and they advised the code was actually being generated by the firing pin on the battery positive terminal due to a duff battery (which I knew was on its last leg and had recently gone flat ...again...) new battery purchased and bingo it reset and stayed off. So sometimes what the code tells you is not necessary the cause. Could have been expensive as the pillar modules are expensive (circa £350 ) and need to be coded to the cars ecu, and I have been told second hand ones cant be recoded?? Cant confirm thats true though.
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