We just bought a 1999 28ft WW. If we plug into the house or run the generator everything works. But just the batteries don't work. We thought the batteries that came with the trailer were bad but after purchasing new ones last night, still can't get anything with just the battery.

Any ideas what is wrong?

Quick disconnect on the batteries???

Is the quick disconnect the pull switch that is in the electrical panel box? We pushed it then tried everything, with nothing working. Then pulled it and tried everything, with nothing.

The inverter is getting really hot though. Does this mean its not working right?

Yes, that is what it is. I am no expert, but this is what I would do next: try resetting the GFI outlets.
I'm sure someone else will chime in soon and have some more ideas. Check fuses as well.

Main DC circuit breaker tripped? My MH has a 55 amp DC main circuit breaker.

is your 30 or 50 amp plug Pluged back in to the trailer? I hope that makes sense. Does every thing work when the gen is on?

Check the 40amp fuse by the batteries. I had one melt the fuse holder and I have blown a couple. The AC still worked when plugged in to shore power but as soon as you unplugged everything went dead.

The same thing happened to me on my last trip. we changed the fuse and everything was fine and the batteries had a full charge.

I second this, happened to me twice, almost took the hauler in to the shop but figured it out with the electrical meter. TWICE!!!!!! Sucks gettin old.

check the fuse by the batteries if the fuse is blown no 12 volts if you notice wire is a smaller gauge up grade it it might be a glass fuse mine was and its an 03 ww

Found the problem, it was the fuse holder like many mentioned. thanks for the heads up, if you wiggle it just right everything works. Where did you guys get replacements for this? Does autozone carry something like that?

I went to a car stereo shop and got a nice fuse holder and I also had the same problem 03 ww