No power to microwave

probable burnt or cracked solder joint on control board

If the control panel lights up intermittently, then you either have a loose connection somewhere near the panel, or a failing component on the circuit board itself.

If you need further help, I’m available over the phone at https://www.6ya.com/expert/david_29ad5d1dd86564b0

Because of the loud snap you are hearing, my guess is you have something shorting out in the high voltage section of the microwave. I'm surprised it is not blowing the internal microwave fuse yet. Average repair cost depending of what part it going bad is approximately $150 to $200. Considering the age of your micro my suggestion is put the money towards a new one.

I had a similar problem. Everyone said must be the magnatron or the fuse ....turned out to be a burned out (visually melted) thermal cut out switch ($12) on the top side of the microwave. Had to get down inside the top of the microwave. The cut out switch was tucked away right up against the the microwave box. Hard to diagnose your problem without looking at the unit in question though, could be several different things. However, my philosophy when it comes to repairs...start with the cheap stuff first!

Look for a fuse on the back where the power cord enters. If not, this is the fix

https://www.fixya.com/support/r29874712-repairing_microwave_ovens

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I had that issue and I opened the unit and there was a fuse near where the power went in. Went to the small local hardware store and they ordered it. It was well under $5 (can't remember) but it still works over 10 years later.
If the fuse blew again I would have trashed the unit.

I discovered the outlet that is was plugged into went bad.

This sounds like the unit is defective and if I were you I would return for replacment!

The first thing to try is a "hard reset". Unplug it from the power line for a few minutes, plug it back in, set the clock, then try again.

It almost sounds like a 60Hz microwave plugged into a 50Hz power line. *grin*

Let us know if the hard reset doesn't fix it.

If not, then there may be problem with the control panel.

Is the cooking time accurate when you use it?

It's never a good idea to use a microwave when it's not working properly, and of course an important rule is to never leave a running microwave.

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