The switch that makes them flash works by heating a piece of metal but I think it would have to be extremely hot to mess that process up. I think you can get another for maybe $5. (Its the larger metal thing in your fuse panel)
The flasher in the fuse box is for the hazard flashers. The one for the signals is the one under the dash. When a lamp filament is broken, the good lamp stays on steady.
Okay, but if both side is doing it at the same moment?
Do this relay is on the driver's side, or passenger's side? or in the middle? I've searched in my haynes manual, but there is nothing about the flasher relay..