The part(s) or condition(s) listed below for the symptom Oven won't turn off are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.
The temperature control thermostat monitors the temperature inside the oven and cycles on the heat when the oven temperature gets too low. If the temperature control thermostat fails, the oven won’t heat. However, this is not very common. Before replacing the oven thermostat, first check more commonly defective components—specifically the igniter and the bake and broil elements. If these components are not defective, the temperature control thermostat might be at fault. The temperature control thermostat cannot easily be tested. If you suspect the thermostat is defective, replace it.
Oven thermostat assembly. This thermostat monitors the temperature inside the oven and cycles on the heat when the oven drops below a set temperature. If the oven does not bake, or if the oven temperature is off by more than 50 degrees Fahrenheit, the oven thermostat may be defective,
The oven control board has relays that send voltage to the bake and broil circuits according to the user settings and sensor input. If one of the control board relays shorts closed, the control board may send continuous voltage to the heating circuit. If the oven continues to heat after it is turned off, the control board is likely defective. If the control board is defective, replace it.