[M30SVX]

It's great to have your expertise looking at this particular problem unit.

Although I have a good working unit, at the moment, I am quite aware that they do fail after a certain working life and I have heard from several owners who have faulty units.

In your opinion, could the contaminant bridging that you found explain the identical way these units fail, ie,
a) round temp setter counts down to 18
b) outside temp button stops working

If you get around to having another look at yours, could you keep us up-to-date with your findings, please?

Would you be up for a repair service for these ACC units (at a commercial price, of course) ??