Main Control Board
If the microwave display is not working the main control board is most likely defective and will need to be replaced.
If the display has gone out the display board might be defective. If the display goes out completely the problem can be either the display board or the main control board. If the display goes out partially the problem is usually the display board.
JES1384SF is a partial model number for a GE Microwave. To see specific parts for your Microwave, please add the last few figures.