Morning Karl
Welcome to the Forum
I am not aware of one, not without actually opening the sealed unit and testing to see if it is a LED failure or something on the PCB
Have you talked to guys like Cartronics or ECU testing as there are so many cars now with LED lights someone must be repairing them surely ?
The alternative (did it with my E70) is a recycled one got mine from Quarry Motors not cheap but below 1/3rd of the price of new
Dave