Model Number: GBD307PDS09
, this oven started displaying an E1 F2 error message that would clear when the power to the unit was cycled, but would return after a few moments once the power was turned back on. An unfortunate problem to have, but one that is absolutely fixable.
Taking a Quick Look
The E1 F2 error message indicates the control board thinks the touch panel has been unplugged from the board or it cannot read the switches. After getting access to the panel, I could see it was indeed still connected to the control board, but when touching buttons on the panel, I noticed some of them would beep while others did not respond at all. This was an indication to me that one of the switch matrix lines that run through the ribbon cable is no longer a complete circuit.
How it Works
The panels on these ovens utilize a switching matrix to constantly monitor all the buttons for a key press. By using a matrix for switch input, many buttons can be read by the processor using very few wires. The unfortunate side of a switch matrix is if any one wire becomes damaged, an entire row of switches on the matrix will no longer be usable since they cannot be seen by the control board.
Testing the Panel
The tech sheet on many appliances that use this kind of panel will have a switch matrix drawn in them so using your meter, you can determine if it is indeed the panel that has failed, or the control board that monitors the switch panel. This tech sheet was no help, but having only a few wires to choose from, it was possible to start taking continuity measurements and figure out which wire was bad which is just what I was able to do after a bit of trial and error. One thing to remember when conducting a test on a matrix is there may be blocking diodes incorporated into the panel so if none of your readings are showing continuity, try reversing your meter leads.
After taking a short time with my tests, I determined that it was the panel that was the problem. I replaced it with a new touch panel and now the error message has gone away for good.GBD307PDS09