10.2.2
Communication malfunction between main control board and display board (E4).
E4
Malfunctioning conditions:
Main control board does not receive feedback from display
board during 120 seconds.
Possible causes:
●
●
Faulty display board
●
Faulty main control board
Troubleshooting:
Communication malfunction
between main control board and
display board
Replace the main
control board.
Check signal wire between the
display board and main board.
Is it properly connected?
Reconnect and retry. Is
error still showing?
Replace display board. Is
error still showing?