Hi, I’m hoping someone has a solution to my problem! My 2014 SQ5 b-turbo diesel suddenly started to run the fresh air blower fan continuously about 10 secs after switching the engine off. With ignition on, I can run the fan up to level 7 no problem. I think the limit of 7 is normal with engine off. With the engine on, I can run the fan normally all the way from 1 to 12 and back. However, 10 secs after switching ignition off, the fan auto-runs (sounding like it is at level 7). If I now switch the ignition on, the fan will quickly run down to the climate control setting (1) and then behaves normally again. I thought simple, it’s the J126 regulator gone faulty. However, I have replaced the regulator (8T0 820 521) twice now and the fault recurs, not immediately, but after a short drive. The fan itself appears to be fine with no sticking or noise. I have noticed that there are several revisions of this part with post letter of A, E and F.is that likely to be critical for selection? The original was Bosch 8T0 820 521 E.