Here are your parts
Parts for Whirlpool RBD305PDS14 Wall Oven - AppliancePartsPros.comSee the attachment for the tech sheet.
Your error is a communication error between the keypad (control panel) and the control board/timer.
Try removing power from the unit for a couple minutes to see if it will reset.
Check all connections at the control board.
Try cleaning the ribbon cable on the keypad and the connector on the control board.
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. Use electronics contact cleaner or isopropyl alcohol.
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.
If neither of the above does nothing then I would replace the control board.
This is a bit of a guess as there is no way to check which part is bad.