TURN OFF all power THEN feel for a warm terminal :)
Sorry to be so grumpy in my prior post. There is only one correct answer to this and I have posted it numerous times and the response seems to be "HUH?"
Something that can kill you is slightly more inconvenient than something that merely breaks or doesn't work right.
The moment you get your 'new-to-you' RV home, grab a flat blade screwdriver go to the AC panel and 1 by 1 pull neutral wires and closely inspect copper wire ends. Shiny as a new penny is the rule.
If a wire end isn't shiny it's time for a replacement buss bar. Home Depot and others sell them.
Next, take several images of the buss before you disassemble. COUNT the number of wires.
Dip the shiny-as-a-new-penny in silicone grease then start inserting them into the newly installed buss bar
When you go to tighten the shiny-as-a-new-panny set screws, tighten the living scronche out of the set screws.
When all the neutrals are done, check the hot line voltage black wires. Every last one should be tighter than hell and it's it's common to hear a 'snap' as the screw loosens. As long as the screw has been loosened pull the wire out of the breaker and check for shiny-as-a-new-penny ends. These you can scrape shiny with a sharp utility blade. dip in silicone grease and then re-install.
After a hundred or so road miles, re-check all screws.
You will not be dealing with this issue again. Sleep tight.
