It could be the fuse, that is the easiest and least expensive to repair.
It could be the heating element. If you have a multimeter an open infinite resistance tells you the heating element is burnt. Not difficult to repair and next to the fuse, the second least expensive.
It could be the board. Again if you have a multimeter call the tech guys at Dinosaure Electronics. Dinosaur customer service page
They can help you troubleshoot the board and have replacements that are superior to the factory boards (and less expensive) if that is the problem. They will talk you through all you need to know to test and if necessary replace the board.
2012 Wildcat Sterling 32RL, Gladiator Qr35 ST235/85R16 Load rating G, TST 507 TPMS w/ Flow-thru Sensors & Repeater, Reese Sidewinder 16K Pin Box, PI EMS HW50C
2009 Chevy Silverado 2500HD CCSB LTZ Diesel, Fumoto Oil Drain Valve, Turbo Brake activated, 39 gal Aux Tank W/ Fuel Pump transfer, Air Lift Loadlifter 5000 air bags.