I have a Simadre CUT50DX that I bought as a non functional device on eBay. The only symptom right now is the O.C. light triggers when the torch trigger is pulled.
The air solenoid activates on the trigger as well; the torch I am using is a P80.
After dismantling, a visual inspection of the boards reveal no burned or damaged components. I found a shorted diode IC on the middle board, and replaced all of them with like components from DigiKey.
The HF diodes on the bottom board tested okay. I have not yet tested the MOSFETs by function, but they did passed a diode test on my multimeter.
I am wondering if you have any other suggestions on where to look. So far all the major components have passed testing