Welcome to the forum
I take it you were using the onboard gen? If so I would start at the gen, there are 2 breakers on the front near the start button. after that make sure the breakers in the power distribution panel inside the trailer are not tripped. It would be a good idea to turn them all completely off and then back on.
Next look for a GFCI outlet that may be tripped. If it is, it wont reset until power is applied to it.
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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.