Sam--the contoller board has a hardwired LC6041 chip. My spare parts
microwave has the same chip and it works. Ever tried to unsolder a 48
pin LC without damaging it thru overheating?

Harry--this unit has only one thermal cutoff switch physically mounted
on the casing surrounding the magnetron--electrically it is upstream of
all loads and were it to activate it would shutdown everything (lights,
fans, control display.. etc)--which is not the case here. Thoughts?
Thanks for all comments--