Wrenchbender, got it! My guess would be that the contact over heated and moved in the plastic. It's possible that there could be some grease or debris not allowing it to make contact with the leaf spring. There isn't any real way for dirt to get into the switch. You might as well buy a new one. The time put into pulling the steering wheel and figure out it can't be fixed, would be doubled if you don't have another on hand.IMHO
Larry