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Replacement parts for FRG PLGFMZ96ECC | AppliancePartsPros.com

Here is the tech sheet / wiring diagram
http://manuals.frigidaire.com/p...pringfield/316441707.pdf

Sorry cannot be much help here.

I am assuming the board goes totally dead, is this correct?
Problem is intermittent so is very difficult to find.
Try to figure out if anything is common to the two board blow outs re: using the broiler, using the mini oven etc.?
Could even be something external to the oven that is putting a voltage spike on the line and taking out the control board.
Has anything been changed/added to this house circuit lately?
Is the oven on its own line?
If not on its own line what else is on the line?

Often manufactures put a crap power supply on these boards, it has poor filtering which lets voltage spikes through, taking out the electronics.
Also could be as you say a wire shorting somewhere only way to find it is to pull the unit and visually looking for a arc mark on the frame/case, the odds here are slim to none.

Hopefully someone else has seen this and can narrow it down.
Throwing parts at this could end up costing more than a new unit.