The problem with our 2016 FR3 30DS was a bad diode in a wire buried under the dash from the fuse box to the blower motor. They tried several things including swapping the dash heater controls with a new unit on the dealers lot before finding the issue. I would suggest you call the FR3 warranty contacts (shown below) at Forest River which have been very helpful in root causing several issues we have experienced. Our fan issue surfaced after only 2,500 miles over the Christmas Holidays when it was difficult getting service at the Dealer or Forest River because so many people were on vacation. Cel Lopez sent electrical diagrams through my contacting him to the dealer to help resolve the issue. Since then I have contacted both Cel and Chris to help solve other problems. Good luck !
Mid-West U.S./CAN. Class A
FR3/Georgetown Warranty Rep
Forest River Inc.
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