If you are tracing a short to ground somewhere the most reliable method I have found is not by using a multimeter to measure resistance or continuity, despite what the troubleshooting procedure might say. Instead disconnect any given wire at both ends by unplugging the relevant connectors. Jumper one end of the wire to machine frame ground and then hook the other end to battery+ via a fused 5A test light. Seen many cases of wires that were hanging on by a thread internally that showed continuity but would fail when asked to pass substantial current. There is a possibility that chafed insulation somewhere may be causing the short to ground in the middle of a wire run. In that case you may have to split the wire you are testing into sections to test it. A good visual inspection before you start may just pay dividends. This may give you a few ideas. It turns out the problem all along was a wire shorted to ground but displayed perfect continuity on a multimeter.........