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Question about Panasonic NN-T990SA Microwave Oven

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Lightbulb no longers turns on!

The lightbulb in my Panasonic NN-T990SA microwave no longer turns on! I've had the more-than-reliabe microwave for the past six years; so I suppose it was time for it to burn out...the problem is, I called Panasonic and they say it's not "consumer servicable." You'd think for such an expensive microwave they'd put in a small bulb access panel to replace it, but they're telling me to send it to a local store for repairs. Help! I'm highly tech savvy, and I'm thinking about opening the microwave case and replacing the bulb myself (since it's waaaay out of warranty already) My questions: #1. Does anyone have any suggestions/tips to go about opening and replacing the bulb in this microwave? #2. What do you think the fair price is that I should pay a service center to replace a bulb in a microwave?

Posted by Erik bouy on

  • Erik bouy Dec 04, 2006

    Thanks I STILL need to discharge the high voltage capacitor even if the unit has been unplugged? (Of course, I wouldn't open it up to this point with it still plugged in)...if so, how do you discharge it? I'm thinking in computer terms were you ground yourself to the something with a grounding wriststrap, which I have, or simply touch another metal object besides the one your working on in order to "discharge" any static electricity in one's body...

    Thanks in advance...



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William Miller

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They do this to avoid liability from your exposure to the instantly lethal voltages present in and generated by your microwave oven. For important safety and disassembly tips, search on (not Google) for all this at once (copy & paste): microwave disassembly.txt safety.txt The oven must first be disconnected from the power line. The outer cover is held in place by several screws on the back and sides, then you lift up and back from the rear to remove it. You need to avoid the sharp metal edges on thge cover and inside the oven. Note there are also catches built into the top & sides of the cover which must be re-engaged upon reassembly, or the cooling efficiency will be compromised. Once the cover's off, if there's any chance you might come into contact with any of the high voltage connections, the high voltage capacitor should be discharged for safety's sake. Once the bulb is located, it can be unscrewed and replaced.

Posted on Nov 22, 2006


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