Several ideas. But first a question: DO YOU HAVE AN INVERTER? Now inverters come in several flavors but for this I'm only interested in two.
Mine, the inverter feeds a sub panel, this is located in a different place from the main breaker panel (Yes I know where it is) and you might have a tripped breaker.. Bedroom, and TV/Electronics bay outlets are common inverter circuits (Mine does not (normally) power bedroom save for the electronics cabinet)
The other kind has breakers ON the inverter, usually two of them.
NEXT come bad connections...
Two possible spots for those
On the slide out, under the slide (May be inside where you need to take stuff apart to get to it) there are two junction boxes.. often there will be an articulated arm (Has an elbow joint) and the wire connecting those two boxes is zip-tied or otherwise tied to that arm. There are also other ways to do this, One of the J-Boxes is on the slide, the other the non-sliding part. Connections inside are suspect. Next page.
The outlets used on most motor homes are not what I call quality.. They are basically punch down devices.
You lay the wire in the track and when you put the back on the wire is PUNCHED DOWN into a metal slot, the metal slices through the insulation and contacts the wire... NOT the best of connections.. This is why I installed regular 15/20 amp outlets for my space heaters, With 12ga wire bent around a screw and well tighteneed.
Page 3.
I have found many RVers have a few screws loose.. Now I know a lot of folks who would agree with that, but they would be wrong since they and I are talking about different screws.. The ones I'm talking about often take a #2 Square bit,, and you will find them in your power distribution panel (among other places) They are SUPPOSED to hold the wires tight,,, one of mine took over 2 full turns before it offered resistance, roughly 3 to Tight.
ALso had one loose on my Power inlet (There is an omitted story to that one)
And I've seen two rigs that had screws loose in the 50 amp Marinco OUTLET on the shore cord, one of them had six loose screws inside the cover,, Care to guess how many screws are inside that cover (Hint, six).
The other just had one.
That about covers the suspect list
Oh, some rigs have a 2nd GFCI hidden somewhere.