Follow up?
 

Thanks for the information.
Did you get the code cleared?
Did you have to put new adhesive and if so what kind?

BMW now has a replacement seal that allows you to get rid of the butyl seal that sometimes fails and allow water to enter the tail light. I just replaced mine this past week. The butyl is messy, but comes off rather easy if you use what you pull off to stick to what remains and pull it off.

Part numbers for my 09:
Right side - 63217288974
Left side - 63217288973