• ** 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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Maytag Microwave MMW9730AS00 repair?


Premium Member
Dec 11, 2019
Model Number
6-10 years
Maytage Microwave/Oven Combo MMW9730AS00. Problems with microwave and had technician come to assess. Said I need to replace the magnatron, inverter, and appliance manager. Cost approx. $1,375.48.

I am a handy person and am wondering if i could order the parts and repair myself? If so, what are the part numbers am I looking for?

Any help is appreciated.

Said I need to replace the magnatron, inverter, and appliance manager.
Did a bolt of lightning hit the control panel?? Did he say it with a straight face?? ...LOL. Yes you can replace the parts. It's not that difficult. Here's the tube and inverter but I don't see an appliance manager listed for that model but I'll look into it.
Thanks! Are you saying it is unusual for all of the mentioned parts could go wrong? There are several problems with the microwave: occasional heating, light out, turntable not turning.
That's hard to say without knowing what the original problem was or if there were multiple problems. It's very rare for more than one part to fail at the same time. That being said, it's possible if the inverter failed, the manufacturer says the mag tube should be replaced at the same time even if it tests good. Unfortunately I don't have any service information on that particular model but I'm still looking. The appliance manager is on the low voltage side and supplies the voltage (120 VAC) to the inverter and the inverter supplies the high voltage to the mag tube. When testing for a no heat problem you need to take a lot of DC volt measurements. If he checked the appliance manager and found it was bad, not supplying the voltage to the inverter, then how would he know the inverter and mag tube is bad. If the appliance manager was supplying the correct voltage to the inverter then why is it being replaced? The mag tube is the easiest to test without power.

If you go by the process of elimination you can end up replacing all three parts anyways. Did he leave you any part numbers for the parts? Do you have a DMM and can you take voltage measurements? I'll need to locate the tech sheet first before I can tell you where to test. My guess, and it's just a guess, the machine was running and counting down just not heating. He was inexperienced and couldn't determine what part failed so if he replaced all three, he covered his a$$ at your expense. Like I said, just a guess.
The guy that came out did not leave me part numbers and only gave me the part names after i pressed him. Probably because he knew i would find the parts and change them myself.

So, of the bad parts mentioned, would it cause the turntable to stop working?

Thanks so much for the information! This helps in my decision to either buy another Microwave/oven combo or repair it.
Unfortunately I don't have the tech sheet or wiring diagram for that particular model so I don't know if the turntable circuit goes through the appliance manager. Usually it's a door switch that causes turntable problems. The inverter and mag tube are high voltage components. No effect on the turntable. Is he replacing all those parts for the turntable not working?? Good lord I hope not!
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