RLMiller wrote:
If you have 126 volts on the neutral bus you have a serious problem that should be corrected before proceeding with the 12 volt problems. See the graphic above posted by RoyB. There should be no breakers on the neutral so that is not the problem. My guess is that you have a floating (disconnected) neutral. This would explain why none of the outlets work.
RLMiller, I believe you hit it on the head. Today I replaced the shore power plug and the 120v worked immediately. I'm guessing the neutral in the plug is broken. Not sure how.
The 12v seems to be the result of some knucklehead (me) leaving a 12v light on and totally draining what appears to have been a failing battery.
New plug, new battery, and we're golden. Thanks all for the input.