• ** 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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721.63263301 Kenmore Microwave Keypad


Premium Member
Nov 20, 2020
upland ca
Model Number
Sears Kenmore
More than 10 years
The numeric buttons and the start button on my microwave touchpad do not work, nor do the auto programed buttons like "Defrost" or "Melt". The display is illuminated and shows the correct time, and the manual programming buttons react to touch, but without the numeric buttons working, the manual functions cannot be programmed or started. The light inside the microwave is also not working. The touchpad and light failed all at once, it was not something that got progressively worse. The door latch is working properly.

Is the problem in the membrane or the control board or...? How can I test the suspect parts?



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Dan O.

Appliance Tech
Staff member
Oct 9, 2004
Ontario, Canada
Is the problem in the membrane or the control board

It could be either or even just the keyboard connection between the two, loose. I would suggest someone first try reseating the keyboard's ribbon connector. Hopefully it's not the keyboard that is defective as it is no longer available.

How can I test the suspect parts?

If the unit's wiring diagram shows the keypad switching matrix, the individual buttons might be able to be tested for functionality. Manufacturers however don't always provide that information so techs often have to just make assumptions about the most likely cause. You'll have to look at the wiring diagram inside the machine to see if that's going to be possible or not.

I can't see the interior light being connected to any of that. IMO it is likely just a coincidence. The bulb can be tested for continuity to see if it is defective or not.

LINK > Bulb and Socket Asm. 6912W3B002L

Dan O.
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