Panasonic Invertr NN-S963, no heat and shuts off approx 7 sec. before end time. Fan works. Is it magnetron? If so, approx. how much to fix?

Magnatron failure is rare. I suggest you check your door interlock safety switch. Do you regularly open the door while the machine is running? I did and I found out that the micro switches (door safety swwitch) are just not up to that kind of abuse. Your maching thinks the door is open because the contacts are burned to the point they do not close.

Unplug the machine, DO NOT TOUCH THE SILVER CAN! You will find the switches opposite the hinge. Check them with a volt ohm meter on contunity setting.

You cam probably get replacement switches at a electronics parts place.

There are other things that can be wrong but you should check these switches first. Cost should be less than $10.00 if you do it.

Let me know if this works for you.

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