Lots of topics on this if you use the search function. :wink:
In a nutshell, common problem on face lift models, c**p design, poor construction, not fit for purpose and should have warranted a recall. :thumbsdown: Original fogs made in Mexico, replacements made in Germany.
Not easy to fix, silvering will be corroded. Someone has done a refurbishment but requires a lot of elbow grease and time.