• ** 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

  • Please note, some of the links on our site are affiliate links (Learn More)

Panasonic Microwave NN-SD670S starts and shuts off after 3 sec


Premium Member
Aug 28, 2016
Model Number
6-10 years
After entering a time and pressing start, the turntable rotates, light is on, fan is running all for 3 seconds and then it all stops. Panel still has electricity as the clock is still visible and ticking.

I've repaired this sucker at least 5 times - door latches, burnt relay switches. Not gonna let this thing go to the landfill if I can help it. Thanks in advance for any tips on where to start checking.
Not gonna let this thing go to the landfill if I can help it.
OK, how much are you willing to pay to keep it out of the landfill? Repaired 5 times? At some point you're throwing good $ after bad. The problem sounds like a board issue or rather a relay on the board. Sounds like you're losing power on the primary side of the HV transformer and that comes from the board.
I know but the repairs maybe cost me $40 since 2011 when we first bought it. Transformers too expensive it seems so looking for a new one. Thanks for the tip!!
If you feel that you have benefited from this site, and would like to show your appreciation.