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Parts for Frigidaire PLEB30S9FCD Wall Oven - AppliancePartsPros.com

Below is a link to a good copy of the wiring diagram.
http://manuals.frigidaire.com/p...assomption/318046251.pdf

First try the flipping the house stove breaker off/on slowly, sometimes you can loose half the line without actually tripping the breaker.

If you look at the wiring diagram you will see that there is a thermal circuit breaker (item 119 in section 05).
Perhaps it has popped.
Remove power from the unit and check it.
If the red button on the back has popped out push it back in.
Be sure that power has been removed from the unit!!!

If this is a the problem, you may want to check the oven temperature with a separate thermometer just to be sure it is not running hot. The unit should be able to be calibrated plus/minus 35 degrees F.
You probably would have noticed if it is running hot as cake/cookie recipes have to either bake for a shorter time or use a lower temperature to get good results.

If the thermal fuse is OK then you should check the power at the unit to be sure that it is getting 240 volts. If you do this be very, very careful as 240 volts is lethal!!!