Last time I was parked where I'm parked (Well nearby, different site) when I was taking down I messed up a couple things and being as I was still connected to the park power while I worked on it.. I got a nasty shock off the steps (I bent them and had to straighten a bit, still need to do a bit more on them).
Well... as it happened, the box was re-built when I pulled in... I checked it with my 3LT and it tested proper... I tested my cord with my multimeter and it tested proper.
Not sure what the problem is.. yet.. but I will find out. (Suspect 1: Connection between shore cord and RV not 100%)