auto wipers

I just picked up my first Toyota a week ago, 1997 4runner SR5. Everything was great until on a 200 mile journey the wipers started up by themselves. I moved the lever through all the positions and back to off but they kept on running. Finally they stopped but started back up again so I pulled the fuse. Anybody had this problem before? Is there a switch in the steering column that could be defective? Thanks for any help or advice.