electrical problem

Looking for suggestions: The situation is that I went to my camper today and found out that I did not have 120V into the camper. I found that my shore cable had a burnt spot on the female end of the cable where it plugs into the side of the camper. I'm 30VAC in a Grey Wolf. I remembered that the last time that I was there, about 3 weeks ago, my TV would go on and off occasionally, but I attributed that to the power company. Apparently, it was problems with my cable. Anyway, when I got there today, I turned on the AC and it started, but then quit. In searching for clues, I found that my voltmeter that I keep plugged into a receptacle inside was showing 0 VAC so I began trying to isolate the issue. I ended up cutting out the female plug completely and wiring it directly into the #10 wire leading into the camper using wire nuts so I would know that I had a solid connection. Bottom line, I have measured the voltage on the outside of the camper where I put the wire nuts and it is a stead 125VAC , but when I checked the voltage on the inside receptacles, I'm only getting about 75V so something is shunting down the voltage. Another clue is that I turned off all the breakers in the camper control panel and I continue to read 110V on the outside cable at the wire nuts as I turned on the circuits one at a time until I turned on the breaker labeled "converter". At that point, the voltage drops down to the aforementioned 75V. Wondering if maybe the power arced at the outside plug causing something to go wrong in the converter. If so, how best to check that? substitute a new converter or what? Any assistance will be appreciated.