Batboard

I have experienced no power up on numerous cdm 750 and always seem to track it to the micro P. Does anyone have any insite on this? It seems as the line on the processor stays high all the time but from what I gather it is only suppose to go high when you power it up.

My understanding was that the reference oscillator goes bad, and for some reason this keeps the radio from powering up. Of course the ref osc is not a field replaceable part.
As soon as I see one that won't power up, I check the power switch and then south of the border it goes.