I'm assuming, we are talking about the upper oven. The lower oven operates by the oven thermostat.
There is no "sensor/switches in the back of the oven". Who ever told you that did not know how your oven works or just lied to you, hoping to get more money.
What part did you replace? You wrote "the control panel". The part which controls the oven temperature is a control board. If you replaced the control board and not the control panel, then the part you've installed is defective. Try to exchange the part.
AppliancePartsPros.com does not sell rebuild parts and they come with one year warranty.
The new control board will cost you $276.89 for the white one and $236.88 for the black.
- The part number for the white control board
AP3095480
- The part number for the black control board
AP3095479
Gene.
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