Your breaker looks like a Sea Dog resettable breaker. On the battery end of the breaker you should see a small round spot that is the reset. It is pushed in now so you might not feel it. This link will show you it -
http://sea-dog.com/groups/683-resett...ircuit-breaker
You’ll need the coach 12 volt layout and 110v diagrams from Thor to see how it is wired in. My diagram definitely shows a 50 amp breaker with 6 gauge wire...but who knows how it was really wired