This is most likely caused by a poor connection at the power post.
The outlet in the power post has lost some of it's "grip" and
that is causing an over heat problem.
Change the outlet in the power post or
move to another spot and I bet it doesn't happen again.
Another thing you can try is to brush on some anti-seize compound
that has aluminum or copper base.
IT IS MESSY!!!!
It will greatly help with conductivity and probably stop it from
You would definitely want to wrap the plug in a Wal-mart
bag any time it was not plugged in because a drop of this stuff
on your hands or clothes will go a long way.
Loctite and Permatex both make it and you can usually find
it at places like Auto Zone or a well stocked hardware store.
It's used for anything you don't want to rust and stick like the threads
on the lugs of your spare tire mount. If you put some of this stuff on
there, you will be able to remove the bolt a year or three from now
It's not made specifically for conductivity but I'm an industrial maintenance
person with 37 years on the job and I promise it will work.
It's also done the trick for me on those darn bargman plug contacts
on your Trailer to Tow vehicle plug.
I use it on battery cables. I've been using it for many years
and I've never had a battery connection to corrode and give me
trouble with this stuff on it.
Again, it's messy if you get it on you but it will do the job.