The high voltage tired was shorted. I replaced it with a new one, but that did not solve the problem.
You can test the high voltage tired with a voltmeter and a 9 V battery. Search Search for it on YouTube.
You can also test the high voltage capacitor, the high-voltage transformer, and the magnetron with a multi met
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er. Search for the procedures on YouTube.
I tested all these high-voltage components with a low-voltage multi meter, and they all checked out OK (after replacing the diode). However the microwave still did not heat food.
When working on a microwave it is important to unplug it and also discharge the high voltage capacitor. The capacitor has a 10 megaohm resister to automatically discharge itself, but it may have failed – – so discharge it manually.
In the end I ordered a new microwave.
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