Im trying to find info on a problem my uncle is having with his TL. Its an 03 and hes been having the wierdest of wiper problems. His intermittent wipers dont work intermittently (they come on slow), slow works, and fast works. But when he goes to turn the wipers off, they dont turn off. Also when he just wants the wipers to sweep, he has to hold down the wiper stick, as they wont sweep once on their own.

He has replaced the wiper stick on the column along with the wiper relay and he still has this problem. Any ideas? Ive tried search but most of the wiper problems listed are because the wiper arm hits the window molding. Thanks!