It sounds like there is probably a problem with the blinker switch itself. This would mean replacing the blinker handle on the steering column.
It could also be a bad connection, but you would have had to had work done recently on the vehicle for it to be this. Meaning that someone worked on something under the dash that could have loosened a wire or connector.
There could also be a problem of a loose fuse, but again, unless someone was working in that area there is really no way for it to become loose on it's own.
I would have the switch looked at.
〉 Answered on Jun 17th, 2007 by Lori Johnson, Owner and Instructor at Ladies Start Your Engines