I was looking at the schematics that chevy82 posted, looks like in the hazard flasher there is "logic" that is probably what is going bad. and i just had the dash off last summer.

My 2001 impala did the same thing. I replaced the hazard switch and it solved the problem. You have to take the plastic piece that stretches across the front of the dash off to change it other than being a little awkward not hard to do. There are a lot of screws stretching across the entire dash but its simple. Once you have the plastic piece off it is as easy as unplugging the old switch and plugging the new one in.