Sorry for lack of info. Here's the short version. About 4 months ago the oven door latch started making noises -- self locking and unlocking and the F9 error would show up on the display (we could not use the oven). We were not trying a self clean. I unplugged a few times and eventually it stopped the error, although the display seemed much weaker in brightness.
Just the other day the dreaded F9 returned and no amount of unplugging will solve. I get the clock up for about 30 seconds and the F9, a loud single beep, and stuck. I can put stop and it resets and does it all over again.
This is a supervisory error and will require the replacement of the display this is part number 74008173, and can be ordered at http://www.apwagner.com/ or http://www.repairclinic.com/