I have never worked on these so cannot be of much help but I can at least get you some info.
Have you tried removing power from the unit for a couple minutes to see if it will reset?
The normal way to troubleshoot problems like this is to check the keypad output with a meter.
Following is a wiring diagram that comes up for this series of units. The problem is that I do not know if it applies to your unit as it looks like it is for a double oven.
http://ww1.dacorservice.com/PartsCatalog/docs/ProductModels/430/Diagnostic_Manual.pdfIf it does apply then you could:
Unplug/remove power from the unit.
Then disconnect the keypad at the control board and check it's key outputs using resistance.
You may want to try the following, though I doubt it will do anything as the error code is for a shorted key and not an open key.
Connector Cleaning / Checking
Unplug the unit
Open it up
Remove the ribbon cable from the keypad to the control board at the control board.
Clean the edge connector.
If it is the type where there is not a connector just the insulation is removed, it can be cleaned with a pencil eraser. Do not use an ink eraser as it is too abrasive.
Check the tracks in the ribbon cable for hairline cracks. A magnifying glass helps here.
Would not hurt to clean the connector on the board. Use electronics contact cleaner or isopropyl alcohol and a tooth brush. Be gentle and do not reconnect till all the solvent evaporates.
Reconnect everything and give it a try.
Another possible way to troubleshoot is to remove power from the unit, unplug the keypad and then power it up again. Just be careful that the end of the keypad harness cannot short to anything.
If the error disappears then I would replace the keypad.
If the error is still there I would replace the control board.
A bit of a crap shoot but your odds are better.
Although your unit does not come up AppliancPartsPros probably sells parts for this unit.
