E90 320i DSC fault code 5E20

[s38b36]

I've read the code myself using DIS and INPA, my local indy have read it and contacted BMW for the repair kit (approx £200). However, BMW want to perform a "diagnostic check" (£100) to verify that the repair kit will fix the problem. Anyone able to comment on the "diagnostic check" proposed by BMW?

[s38b36]

Repair kit fitted and DSC fault now resolved. I did not take it to BMW for their diagnostic check.