• ** 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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WMH31017AS2 KitchenAid Microwave won't heat


Feb 7, 2021
Mahwah NJ
Model Number
6-10 years
hi & TIA for help/intel. I've read a bunch about microwaves, taken mine apart, tested components, etc over the last 24-48 hours and I'm stumped.

Wife & I made a mistake and left one of those magnet cover things attached to top of unit while running.... and now it won't heat.

I have a Whirlpool WMH31017AS2 (purchased in 2014) that won't heat. A few weeks ago my wife bought one of those splatter cover things with magnets, and didn't read the directions (ok I'll admit, I didn't either) which plead with you not to leave the cover attached to the top of the microwave while running. We used it properly (ie, covering food) a bunch of times, but a handful of times lazily left it attached to the top of the microwave while it was running... and now the thing runs but doesn't heat food. (Microwave had been operating normally until then.)

So in my research, I was prepared for it to be the magnetron... except that when I tested the magnetron with my digital multimeter it checked out fine. (And visually it looks ok too, not browned out or fried-looking.) Tested the diode which seems to be working as intended, and the capacitor as well. So.... any ideas? I tried figuring out what part of the microwave those magnets would mess with but haven't been able to find anything online.

Any insight is greatly appreciated so I can hopefully just replace the needed part and not the whole unit. Photos attached (except of the magnet cover thing, in a fit of rage I threw that in the garbage ;)



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