Originally Posted by ard

You have a link to that other thread where "mechanics" have said it must have been a fouled sensor that was subsequently "washed off" by the snow and water? Did quick search and could find nothing....

But anyways.... buy a code reader- better yet a 'Peake' BMW specific reader. If your car is out of warranty it is invaluable. Even if you are not a DIYer, it will let you be better prepared to walk into a shop.