welcome to the forum
If the fresh tank is full and it's only a dribble, odds are there is some construction debris in the drain. You can use a small diameter long screwdriver and poke it up into the tank. Depending on how much water is in the tank you may get wet
If the tank is empty and your just concerned about freezing, your tank will be ok since it will act like a giant ice cube tray.
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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.