I feel your pain, had a similar issue with mine. The operation of this thing is so simple but can seem so complex.
Follow an electrical schematic and verify the 12 volt fuse on the control board has power through it . Measure the resistance of the 12v heater. If ohmís are within specs you probably have a bad control board
If replacing the board I suggest replacing the face panel board also.
You can purchase on Amazon for about $300 for both
The control board has a rather high failure rate and is diagnosed by simply eliminating the other components