JBMSR, you're thinking 120volt, his problem is 12 volt, so I don't think that's it.
Vinval, you probably have switches by the entry door, make sure that the two that say something about 'battery' are both turned on. (they all have different names from RV to RV, so it's hard to say exactly how they might be labeled).
BTW, I'm in Jax just on the other side of the bridge, could maybe stop over some time (or you come to me) and we could figure out some things together.
You can PM me here or on iRV2 (where I spend more time) if you'd like to.
2013 Winnebago Sightseer 36V