The temperature sensor are quite sensitive. Use a soft and damp cloth to clean it.
If you use intend to use brake cleaner or WD-40 which is a petrol based solvent, it might cleared some dust that is preventing the vane from moving freely.
Most of the forummer have try this before but unfortunately the problem come back again after a few months in service.
If your AFM's vane stuck due to oxidation problem, I doubt any solvent will dissolved it. For a more permanent solution, filling and polishing off the oxidation on the moving part would be a better option.
My advise is to open up the AFM and check the swing movement of the vane.
However, in some cases as discussed in other forums, worn out "resistor track" for the AFM could be also the cause of AFM failure.