John,
I did check the shore power. However, when I opened all the circuit breakers in my Oliver, the shore EFCi still tripped. So, that should indicate that the electric power cord itself is bad, or the adapter that you attach to it to plug in a normal plug is bad. After disconnecting the power cord to the camper and just plugging in the adapter and the clean power checker I had, the shore circuit still tripped.
So, I’m suspecting, and hoping it is just the plug adapter that is bad, not any circuit of the camper itself. What do you think?