I have Motorhome an a Ford f53 chassis. I am having a problem with headlights, horn and windshield wiper. I have checked for broken ground wires, with nothing found. The Headlights do not work even though there is power to them(all upper and rear marker and taillights work). The horn does not work. Any time I hit the horn, the high beam indicator flashes. The wipers only have one speed and the delay does not work. If I tap the wiper arm for single wipe, the wipers will stay on. The only way to stop the is to shut off and restart the engine. Is it the wiper control assembly has gone bad or is there another ground wire somewhere that I missed?
Sounds more to me like some wires have become worn in the steering column. The insulation probably wore off, and now they’re touching which is causing the various components to behave strangely. Depending on where the wear is, this could be a cheap or rather expensive fix.