Question about Jenn-Air JMC8100 Microwave Oven

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Oven continues to blow fuses.

The magnatron, diode, and motherboard have been replaced and the fuses continue to blow when the machine is turned on. All parts show continuity and there is no obvious short in the machine. What should we do?

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If it goes dead or blows the breaker (or GFI) when you plug it in or open or close the door, then there's a problem with a door switch or door switch mount.

See http://www.microwavedisplay.com/doorsw.txt

If it went dead almost immediately after pressing the Start pad, that's usually a shorted high-voltage capacitor.

If it went dead a few seconds after pressing the Start pad, that's usually a failing high-voltage transformer.

Here are some links you or someone you know can use for test help, but read the safety warnings first:

http://www.gallawa.com/microtech/cap_test.html
http://www.gallawa.com/microtech/xformer.html

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

Posted on Sep 09, 2008

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