I see that this is a rather old thread, but the issue with the 50amp auto reset breaker on the jack system occurred to me this week. Yes, you can purchase a new one from the auto parts store, but sooner or later that one is going to do the same thing. You can also purchase a manual reset larger one which will fix it excepting if the breaker pops you got to reset it. Here is a link to high amp auto reset breakers in various sizes that can be use to replace the lower quality 50amp auto rest breaker. I used the 60amp one, works for me.

https://www.delcity.net/store/Del-Ci...93071.h_194987