Portable Generator open ground

The "open ground" diagnosis is not correct. It's the most likely guess by the EMS based on what it can discern from the two hot wires plus the safety ground wire. When you're on shore power the open ground diagnosis has a high probability of being correct. When being powered by an unbonded generator, it's an incorrect diagnosis. Shore power has what's called a "neutral-ground bond", where the neutral conductor and ground conductor are connected upstream of the power output. The majority of portable generators do not have this neutral-ground bond, and the EMS wrongly diagnoses it as an open ground. To make the EMS happy you need to add this neutral-ground bond. Many people think the simplest way is to take a standard plug and wire the neutral (wide blade) and ground pins together, then plug it into the same generator outlet that you plug the RV into. There have been pictures posted, but with the forum requiring pictures to be hosted on an outside web site, all the ones I know about are gone. Take a look here for more info: http://noshockzone.org/generator-ground-neutral-bonding/ . To read more, search for "generator bonding plug" and you'll find lots to read, videos, and even pre-made ones to purchase.