Also, if you ever have the opposite problem, where you are getting no 12V power unless you are plugged into shore power...there's an in-line fuse just behind the battery in the wire that comes from the battery and into the camper. Looks like a little red rubber box that's in the line. Pop the top off and you'll find a fuse in there. It it pops the only thing you can run off the battery is the power lift - you'll get no 12 V stuff working in the camper.
Ask me how I know this....
2012 Flagstaff V-lite 30 WTBS
2011 Ford Expedition
4 kids and a hubby & never enough time to camp!
2011: 17 nights 2012: 26 nights 2013: 46 2014: 20 2015: 16