I haven’t looked into much on my 135i , but my daughters X3 has had the control board go out on the left rear side. So I found replacement control boards on Amazon
https://www.amazon.com/light-Repair-.../dp/B079V1WBLN
But I opted for these LDD drivers for less and less worry on burning out again. Let you know how it goes.
https://www.ledsupply.com/blog/commo...ail-light-fix/