Someone from the park came and checked the 120 v 15 amp gfci and said it wasn't their problem, had to be mine????
I have had to tell a CG owner to check their shore station so many times and them saying it's ok, I can't keep count. They DO NO check for open ground, etc., only if there is power there. I shove my tester and show them. And most say oh that's ok you still are getting power from the pedestal. Open grounds etc do not trip breakers.:S
Buy one of these. find it at any hardware store for 6 or 7 bucks
Plug into shore station to test then plug into your RV.
It will tell you exactly what the problem is. Doesn't get any easier than this.
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I check the shore station with this 'before' I plug in and then it gets plugged into an outlet above the sink in the RV so that I can see every minute what's going on or not with the electric feed in at a glance.