[RayChez1]

I believe you are right. I believe that you have a ground wire on your twelve volt system that is not getting a good ground and therefore you are not getting good continuity off your house batteries. Check all your ground wires coming off your house batteries.

Which Xantrex shop did you contact? "The one in Portland Oregon has a good reputation on fixing inverters and a very knowledgable young man was the tech when I visited last, about two years ago. Not sure if the same person still there, but if you have not called the Portland Xantrex shop, I would give them a call.