Since you are blessed wit( an outside access panel gaining acccess to the control board, sail switch, blower motor, etc is easy.. take that black outer panel cover off
Sail switch is held in b6 two screws, remove it and test with a multimeter while moving paddle arm back and forth to verify continuity
Also.. folks sa6 clean the sail switch.
All you can clean is the area around the arm of the switch..you can’t clean anything else unless you drill out the rivets to gain access to the contacts inside.
Spraying compressed air or any liquid contact cleaner is a joke at best.. IMO
Watch my video showing a typical Saul switch being taken apart and why spraying contact cleaner etc will just cause more issues
https://youtu.be/Neg5E0WemgY