Battery switch questions

[Beachseeker]

I've found that my battery only seems to power my tongue jack and maybe my emergency brakes.I get that it is only going to power 12v dc devices. I dug into the front storage (glad I have long arms) and found the switch, chrome bell shaped handle, in the "IN" position. Pulled it out. Still doesn't power interior lights, fridge, etc... Tongue jack still has power - with AC disconnected.

Ran out of daylight to continue troubleshooting today. The trailer was plugged in all winter, Michigan, and I would expect the battery to be dead as in need to buy a new one if it had gone dead over the winter. So if that's the case I'm not sure what's going on.

Like I said, ran out of time today just looking for some insight into how these systems work. I have and know how to use a voltmeter. I just don't have a set of electrical prints to reference...

[mjpguy]

Beechseeker, I've tried 3 times to reply to you're post with help and every time I hit "post" my reply disappears. and says I'm not logged in (I am) so if ya need some help. let me know here and I'll try and help thru some other means. For some reason, this goes thru....?