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Panasonic Model NN-T994SF runs for approximately 30 seconds and stops. The unit still has power to the front panel and can be restarted (for an additional approximate 30 second interval before it stops again) and does not appear to be cooking at all.

Posted by Jdubya on

  • 2 more comments 
  • Jdubya Apr 09, 2008

    Been there, done that....this symptom doesn't appear to be my problem in this case.

  • Jdubya Apr 09, 2008

    I have 120V AC going into the PC board and 9.3 V AC coming out of the power supply going to the Magnetron unit when I simulate and initiate a cooking cycle on the front panel. I was hoping you folks might be able to provide the output of the PC board to the Magnetron unit or email a suitable schematic with outputs of the components at the test points within the PC board. This would allow me to 'shoot the bug' down to the component level and save me some time and money.

  • Jdubya Apr 10, 2008

    Yes, very informative WEB pages! After performing the Magnetron test I found that I have a shorted Magnetron according to the procedure (0 ohms resistance between the terminals of the Magnetron and its metallic case). But I also wonder if I have another bug in the oven since the oven simply stops before the alloted time period is reached. I suppose I am trying to understand what regulates the timer in the microwave circuitry and why the oven would stop prematurely. Could a defective Magnetron unit have affect on this timer circuit?

  • Jdubya Apr 10, 2008

    Thanks for the help!! Good job!


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In Canada, you can find an authorized Panasonic servicer here.

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