Microwave over the range microwave model #MH7130XEZ-0, serial # FGG0402569. I disassmbled the display panel to clean it. Disconnected the circuit board, removed from plastic panel, cleaned panel and reassembled. Reconnected the connectors on the circuit board , reinstalled the touch panel display to microwave oven, then plugged in power cord. Diplay initially displays 88:88 (for less than a minute) then displays "F2" and a single beep every 10 seconds (like the reminder beep). The touch panel is non responsive to any buttons pushed. So I unplug the power cord. Help..do I really need a service call?