Unplug the unit and access the board to inspect for any evidence of component damage (like a burnt or discolored resistor). If there is, replace the control. If not, check the power at the outlet. If you have 120VAC at the outlet, you probably need to replace the board. Try powering it back up after about ten minutes, or more, after it was unplugged. If the error code doesn't go away, you probably have a bad board. I believe it's a complete assembly.