Did the car sit or not get driven much? My car sat in a barn for 14 years and just about every switch and electrical connection was oxidized. I just cleaned all the connections I could with some extra fine sandpaper or a pencil eraser(erasers work pretty good). My dash lights didn't work either until I cycled the dimmer switch about 20 times ON and OFF. It's a long and boring process but may be a simple solution.
