My name is Peter. I am a retired field service appliance technician.
You did not provide a model number and manufacturer. So, the following is a general description of a F4 code.
The error code "F4" will be displayed along with a beeping sound if the ERC (Electronic Range Control) or "clock" determines an open oven temperature sensor circuit during the "cook" (bake or broil) mode. The "F4" message will not be displayed in the time of day mode. The cause of the problem is a bad oven temperature sensor or its wire harness. The access to the oven temperature sensor plug and the wires is from the back only. You have to pull the oven out of the wall (if it's free standing) or remove it from the cabinet (if it's built in). Disconnect the power and remove the rear cover. Check the resistance across the oven temperature sensor. It is supposed to be about 1100 Ohms at room temperature. If the resistance is incorrect, the oven temperature sensor is bad and needs to be replaced. If not, check all the wires from the oven temperature sensor to the ERC. If it is not the sensor and wires, you have to replace the ERC.
To get the right replacement part just click on the link AppliancePartsPros
, then type the model number of your oven in the search box, click on the "search" button and in the new window type the word "sensor" or the word "clock" in the "search by keyword" box and click the "search" button.
You can go into the following website put in your model number and get diagrams ans component part numbers.
Your model number is on a label either on the face of the oven when you open the door or on the side of the oven door.
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