My 2006 325xi wagon had the same problem at 42K mi. Brought Tenafly BMW, they wanted $200 just to run the diagnosis. Plush extra to fix if there is a problem.. I asked if there is a recall. She said no.. Then I brought my car to my mechanical in Palisades Park, NJ. The owner ran a test, reset and turned off the lights. DONE! He said it could be short wire or the sensor. But at least the lights are off. I tipped him $10...
(BTW, the owner at Alltech has been treating my bimmer like his car. Highly recommended)