Using the multimeter check the both oven sensors for resistance. You should read around 1100ohm at room temperature. If it's different - replace the sensors
Part number: 74008369
If the the sensors are OK (most likely they are) then replace the control board Part number: W10169130
Here are the breakdown diagrams and Control Panel and Internal Controls parts for Jenn-Air JJW9827DDW - AppliancePartsPros.com
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