• ** REMEMBER! **The microwave can still shock you even unplugged!!

    ALWAYS discharge the high-voltage capacitor first if you even think your hands will come close to any HIGH VOLTAGE components.

    Jeff mentions this: Anything in the high voltage ( magnetron, capacitor, diode, wires to and from ):
    ...Use a metal ( not the shiny chrome type ) screw driver with a insulated handle to short across ( touch both at the same time ) the terminals of the high voltage capacitor to discharge it.

    From Jeff's site: http://www.applianceaid.com/component-testing.php

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FIXED WMH53521HZ3 Microwave starts and cuts off after 2 sec.

While you’re looking, see if you have a fuse near the transformer in a plastic holder like the white one shown in the image. I’ve seen microwaves with this fuse and sometimes it’s not on the schematic or parts list. I have one in the shop now with one in a black holder rather than white and it’s not on the schematic. It will create a run and no heat issue.


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I just checked and get no120v to the transformer.
So even though all relays tested good out of circuit seems something on the control board is the issue?

Also I did have the fuse but it’s built into the board now. I’m guessing an updated design.


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No, sir, that is a different fuse. If that one was bad, you’d have no power to the microwave. If you’re getting 120 V to the primary of the transformer and it is shutting down, and all your switches test good, that sounds like you could have an issue in the high-voltage section or the main control board.
I’m not in demo mode anymore. So most likely the board as you said. I will troubleshoot the board a little more and see if I find something.

Appreciate the help

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