Welcome to the forum
First thing is to verify that you indeed have 120VAC at the outlet. It's possible that you have tripped a breaker in your HOUSE service panel. Once your sure you have 120VAC going to the trailer, check the microwave in the trailer, does the clock or display light up?
Have you checked the voltage at the trailer battery(s)? It should be above 13VDC, if not then your converter may have failed, or the fuses that control the output of the converter have blown. Those fuses are not on the panel that you see when you open the cover, they are located on the converter itself.
If you have an integrated converter, it will be on the bottom half of the breaker/fuse panel. You'll need to take the cover off to see it. If you have a separate converter, it will be plugged into the back side of the breaker panel, or have romex coming from a breaker. The breaker will be labeled "CONV".
Verify 12VDC coming out of the converter, should be two large gauge wires, as a rule white is negative and red or black is positive. The posts on the converter will be clearly labeled. Post back and we can go from there.
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2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.