The limit switches mounted inside the gear case on the motor do go "bad" or out of synch . . . had same thing on 70 300 or Sport Fury . . . the relay is just a relay to feed the motor . . . there are service kits for the gear case as it is just a nylon gear in there and the limit switches. Usually I have found it is just a case of the limit switches (contacts really) needing to be cleaned and adjusted . . .they are just a couple of copper contacts . . . sorry, I don't have a motor handy to show pics . . .