To take care of the upper oven problem you need to replace the upper relay board Part number: 74006612
For the lower oven first check the resistance of the oven sensor. With the multimeter set to 10 Kohm at room temperature normal reading about 1100 ohm. if the sensor checks OK - replace the lower oven relay board
Part number: 12001914
Oven sensor Part number: 12001656
Here are the breakdown diagrams and Replacement parts for Jenn-Air WW27430B WALLOVEN- S/C ELE | AppliancePartsPros.com
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