Originally Posted by 5picker
I asked him if he checked the voltage at the battery.
He said it was 13.5v at the battery with the converter on and then disconnected the wires and had 11.6v.
How could the converter voltage not be getting back to the battery?
You can get good V readings on the cables but the power is not getting through (or not fully) if the battery wires are not solidly attached. In essence you are testing and jumping current from the wire from the converter to the wire that is attached to the frame/ground. In the future I would suggest testing at the cables AND just touching the battery terminals themselves to see if it's the same reading.
Two bad new batteries at once that are both seems like a crazy anomaly. Not accusing anyone of anything but two incorrectly installed batteries at once is way more likely and could have damaged the batteries too.
Interesting to see how this turns out.
Land of 10,000 Lakes
2016 Forester MBS 2401R
Nights camped 2016: 19; RV to date: 22