||I'm still having wiper problems and I'll value any responses. RV dealership solution was to replace the Fleetwood wiper motor; didn't solve problem. Then they said it was a ground problem; cleaned up battery terminals and added ground wire to wiper motor. Just rained yesterday, and the wipers are still erratic. What happens is they travel across the windshield and stop in various places, about a minute later, return to stored position. Sometimes, it appears to happen more slowly when under acceleration (but this is not a vacuum system). All of this happens at any wiper switch position, i.e., low, high, or intermittent.
The wiper switch is Ford (F53) and part of the turn signal switch cluster. I'm thinking two or three possibilities. Since it occurs at times while under acceleration, perhaps low voltage to the wiper motor causing it to temporarily shut down? Or, a defective wiper switch causing the intermittent function to activate regardless of the switch position. I suppose it could be a loose connection or intermittent short somewhere, but I haven't been able to isolate it by jiggling the wiring/switch (where it's accessible, plus, the wipers generally work while parked with the engine running and stopped).
The dealer works on the Fleetwood items, but won't touch the Ford chassis parts, go figure! I will treasure any thoughts on this most annoying problem.