Question about Panasonic NN-S254BF Microwave Oven

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Faulty microwave oven

My microwave oven doesn't warm up food & cook it has just shutt down

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Re: faulty microwave oven

So it's dead? (No lights, no beeps when you press a key?)

A microwave can be dead for many reasons.

If it goes dead for a while during or after cooking then comes back on, the magnetron is probably overheating and causing the thermostat to open. When it cools, it closes the circuit and allows power through again.

If it's random, it may be a bad connection, usually on the control board or fuse holder.

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.

If the fuse is good, it may be an open thermostat or thermal cutout on or near the magnetron or on top of the cavity / body of the oven.

But - this model uses and inverter. Due to the lethal voltages used and produced, I do not recommend that an inexperienced person work on these.

I would recommend that you contact your nearest Panasonic-authorized servicer. You can find one here:

But if you or a friend decide to look into it, we have critical safety information and disassembly information at our site, linked here on Fixya:

Posted on Nov 18, 2007

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We're happy to help and we appreciate your thoughtful rating of our answer.

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