I now decided to work on the charging system.
All it took to repair the charging problem was a new regulator. This picture shows that the wire from the isolator to the house battery had been cut. I wondered why.
You can see that the connector is melted. That was why it was cut. This is usually caused by loose or corroded connectors.
This the other end of the wire. I was going to run a new 10 gauge wire from the isolator to here, but by that time, I had decided that Buttercup was a money pit. I gave up and donated her to the Disabled veterans. I also realized that as a new full-timer, I did not need another motorhome.
This winter, I am working to make up for the money I spent on something that I didn't need.