The electrical power to the oven needs to be disconnected. The touch panel needs to be cleaned and dry. Touch the center of the On/Off key with a flat part of your finger. Check the wire harness between the user interface and the electronic oven control board for damage if the key doesn't work again. If the wire harness is damaged, replace it. The user interface should be replaced if the wire harness is okay. The electronic oven control board needs to be replaced if the problem continues.
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