Display is not turnings on

I have a Kenmore model 592-89032. The problem I have with my dryer is that it doesn't turn on at all (the display doesn't show anything after pressing the ON button), but it gets power, and the door lamp turns on and off.

At first, it kept stopping mid cycle, showing an FE error code, and not turning ON after that for a while, but it responded when I was pressing the ON button. Recently, this solution didn't work anymore. I checked all the thermofuses and sensors, and they all seem to be working. I think I should check the main board, but I have no idea where to start. (FYI, the 592 models are made by Samsung, and for finding the parts, you better search for Samsung dryer parts, not Kenmore.) Any clue on that?