Anyone having the same problem with MICROWAVE MELTDOWNS?

I have just had my third microwave shut down on me! This stainless beauty, that grilled all meats & vegees, poached a perfect egg, baked brownies and cakes, heated drinks, made popcorn, defrosted everything, and more just died. I checked the fuse, its OK. I searched for any type of loose wires or parts, nothing. All is clean and new looking. The schematic shows two switches in the door, a heat sensor & flame detector, and more, but how to test theses parts? Has anyone done this before. I hate to landfill this. Its probably a simple fix but where to start? Thanks , Triumphman ( Pro Member) 

I think you may have done something to offend the gods.

In particular, I think you may have offended the god, or gods, whose dominion is the successful operation of microwave based food-cooking appliances. I'm not sure which god has dominion over microwave ovens, maybe Hephaestus?

Try to think back.  Did you injure, or offend, anyone who was the son or daughter of a god? 

I mean that's the way it happened for Odysseus. He accidentally (kinda) blinded  Poseidon's son Polyphemus, and as a result of that mishap he had a lot of trouble getting home.  You see Odysseus had to cross the ocean to get home, and the ocean is the dominion of Poseidon.  So basically Poseidon, via his control of the ocean, made it very difficult for Odysseus  to cross the ocean and get home. You know there were storms, and unfavorable winds, and um... yeah.

Anyway it just seems strange to me that you would have such problems with microwave ovens.  To me the ol' micro has always been a very robust kitchen appliance, and I have had little trouble with them.

I remember way back in Oh-nine, I think it was,  you were have having some sort of trouble with the microwave, as described here:

And you were nice enough to select my answer as least-worst. I appreciate it.  Since then, I can recall answering one other microwave-is-not-working question, here:

And I think I did a better job answering it that time.  To reiterate what I said that time, basically there are a whole bunch of safety interlock switches, all in series with one another, switches in the door, a thermo-switch... You mentioned a "flame sensor".  That's a new one to me.  Anyway, basically, there's just a whole bunch of switches, and they all have to be working, in order for the magnetron tube to get energized and, you know, cook your food for you.

By the way, the way to test a switch to determine if it is working is by using ye olde continuity test.  Perhaps your multimeter has such a function?  If it does not, a closed switch looks like just a few ohms (or less) of resistance, and an open switch looks like an infinite resistance, where infinity is basically higher than your meter can measure, typically > 107 ohms.

I recall two microwave ovens I successfully repaired that I can remember somewhat clearly.  The first (you never forget your first) was a microwave oven that I bought at a garage sale, for 5 FUSD.  It turned out the reason that microwave was not working was due to a failed thermo-switch.  It was this little two terminal device that bolted to the top of the whatchalit cavity wherein the food gets cooked.  Replacing it with a paperclip made the oven work, and I think for that one I actually sought out, and found, a replacement thermoswitch.

The other microwave oven repair that I remember clearly was a microwave oven that belonged to my mom.  The problem with that one was that one of the interlock switches on the door had burned out, and in retrospect it made sense because she was always pulling the door open, i.e. part way through the timer cycle, without bothering to push the "stop" button first, because  she knew that opening the door would cause the oven to stop, "automatically".  I don't know why anyone would place such naive trust in the designers of these safety features, to just trust that that would always work, but it always did. 

However it turns out this is one of those things that makes the microwave gods angry, or another way of saying this is that it puts a terrible strain on that little switch inside the door.  For a 1100 W oven, that's like a 10 ampere current that needs to be broken, and doing it repeatedly will destroy that little switch in the door.

Anyway, that's all I've got for you, except that I also advise you to please be careful.  Please do not be touching anything in the oven when it gets energized.  There are dangerous high voltages, and strange forms of energy present... when everything is working correctly.