98 f150 - wipers started acting up. 1st the delay/variable speed quit working and the wipers would not go to the bottom of the windshield win turn off- stopped where they were. Now they quit all together. Is there a controller that can be replaced. Tonight I will test the motor but given the symptons I seems like something else.

 

I've had same problem, this fixed it.

http://www.fordf150.net/howto/fix-in...er-problem.php

 

I would expect the motor to be shot. That or a fuse but probably just the motor. Mine were acting weird, not shutting off, washer staying on too, delay etc. I replaced the alternator again and they seem fine anyways, for now. Consider that if not the arm itself. Apparently I had some diodes blown again but I replaced it because it was noisey. Sometimes you fix more than you expect, if that's the case, no complaints here.

 

pulled the motor and found that one of the 5 prongs on the motor corroded and broke off.