Our daughter had the same issue with her 2015 Sunset Trail. That's the converter running. It is caused by using a certain amount of power and it needs to charge the battery continuously.
The way to make it stop is to use less power. You can turn off a bunch of lights, or you could do like our daughter did and changed the light bulbs to LED ones which use a lot less power.
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2012 Cruiser Sahara 330SS
2015 F250 Super Duty diesel
Not sure Lloyd. I know mine would go silent as it reached full charge but not sure if it stopped. Never looked at the converter that close. Now that I went to LED, I very seldom even hear it except if it has been discharged from sitting without power for a few days.
Fan should not run unless there is a need to cool converter. Do you have something plugged into your 12v plug? Laptop or chargers or 12v/110 converter?
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It was a rainy few days at Algonquin Prov park...tarps kept us dry.
Wayne --Belle River (Windsor), Ontario
2013 Sunset Trail Reserve 25RB..(just sold it)
2015 White Chev Silverado 2500HD 4x4 (6.0 l gasser)
2003 Mountain Star 890SBRX Truck Camper
our cruiser 5th wheel did the same thing until I changed all the lights to led bulbs.
I bought them on ebay from China. They are the little square flat panel bulbs with 48 Leds
Only ran about 30.00 for all of them. It also eliminated a lot of heat that was produced by the regular bulbs.