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If you look at the power distribution center, one side has breakers for the 110VAC appliances and the other side has fuses for the 12VDC appliances. Often times at the top or bottom of the fuses you will find a large rectangular thing plugged into the fuse slot. It is a thermal reset circuit breaker.
With no power to the switch, I would check that. Everything else 12V works?
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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.