On for 2-3 seconds and shuts down with slight wire burning odor.

There might be a problem with door switch for your microwave to be turning off after 3 seconds and the door switch will need replacement on your microwave.

Hello -

It is probably safe to use the microwave oven after removing the burned smell.

I found some methods for removing a burned smell from a microwave.

From:
https://blog.bostonappliance.net/5-foolproof-ways-to-get-burnt-popcorn-smell-out-of-the-microwave/

(Quote)
1. Fill a bowl with 1/2 cup water and 1 tablespoon white vinegar.

• Microwave it for 4-5 minutes and leave it with the door shut for 10-15 minutes.
• Steam will loosen smell-causing detritus stuck to the walls. Vinegar absorbs odors, even stubborn ones like burnt popcorn smell.
• After the waiting period, remove the bowl and wipe the inside of the microwave down with a paper towel

2. Not good enough? Okay - soak a sponge with vinegar.Place some baking soda on top and microwave the sponge for 25 seconds.

• Wipe the inside of the microwave with the sponge.
• Don't forget the glass tray and the microwave door.

3. If steps 1-2 don't remove all the grime, soak cotton balls with acetone-free nail polish remover and wipe down the inside of the microwave.

• Even stubborn stains should come out.
• Wipe down the inside with soap, then vinegar water, to remove the polish remover.
• We recommend following through with step 4 to get rid of chemical smells.

4. Banish the remaining smells with the power of citrus.

• Peel two oranges or slice a lemon in half.
• Place the orange peels or lemon slices in a bowl of water (1-2 cups).
• Microwave it for 4 minutes. Watch closely to ensure that the water stays in the bowl and the citrus peels do not burn.
• If possible, leave the bowl in the microwave (with the door closed) for 12 hours.
• Too time-consuming, or just not doable for you? That's okay too. Let the bowl sit in the closed microwave for half an hour then, if the burnt smell persists, continue to step 5.

5. Still bad odors in your microwave? Leave an open box of baking soda on your microwave tray overnight.

• It will neurtalize the odor without adding to the smelly situation in any way.
• You can also place coffee grounds from your morning coffee in a bowl in the microwave all day while you are at work.
• If you don't mind coffee smell, you can microwave 2 tablespoons of coffee grounds in a half cup of water for 2-3 minutes to expedite the process.

(End quote)

Best wishes.

Betty, it sounds like you might have 2 problems and the power shutting off could be an end result of the metal odor you described. The power shutting off, more than likely is just a blown fuse. That is usually a simple and in-expensive repair. The metal odor could come from either your magnetron or from the high voltage transformer. Either one of those is going to be a rather expensive repair and if repair part stores in your area are anything like in my town, unless you repair them for a living or know someone who does, you can have some difficulty in getting those parts. Sorry for the bad news, but it might be simpler to just replace the microwave.

Diagnosing Panasonic microwave oven stoppages:

If it stops after 22 seconds, that means the controller has detected a problem, usually a problem with the inverter, controller, magnetron, or a bad connection from one or the other.
If it stops at 16 seconds and is a sensor model, it probably has a defective humidity sensor.

If it stops after 7 seconds, it has a problem with the inverter.
If the digital programmer circuit / controller does not get a feedback signal from the inverter for a period of 3 seconds, the controller will stop the cook cycle.

Or see if this describes what's happening:

Put in time, push start and unit runs for 2 seconds, relay clicks, unit goes off. Cook time on display goes off and clock time comes back. Bad upper interlock switch and charred connector. If so, see:

http://www.microwavecontrol.com/safety.htm
http://www.microwavecontrol.com/disassembly.htm
http://www.microwavecontrol.com/doorsw.htm

It may be a loose connection in the wiring between the inverter, magnetron, and/or control board, or maybe one of those components has failed.
Due to the complexity and lethal voltages used and produced in inverters, I do not recommend that an inexperienced person work on these.

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

If you have other questions, please feel free to contact me directly (see below). .- William E. Miller, AS-EET
[email protected]
http://www.MicrowaveControl.com
Microwave Oven Control Panel Repair Nationwide
"Recycling by repairing since 1982"

The problem is that the magnetron is arcing when it is running and it has found a couple bare spots 'exposing the metal'. The microwave uses a special industrial white enamel paint to prevent arcing, it is very important that the oven be removed from service until the situation is rectified otherwise there is a danger of shorting out the magnetron.

Sounds like Magnetron MAY have shorted or an HV rectifier shorted.

Also there is a resonating cap for the current limiting trnansformer typically. That may have shorted.

Repair shop is in order.

there should be 4 screws holding it in.. and one plastic connector with 2 wires in it that are plugged onto the mag..
the seal would be the gold colored mesh around the antenna of the mag. when you take the microwave down you would take the cover off and if looking at it from the back you would look towards the right side and there should be a thermostat there that may have started to burn up. if it is replace it and the wires.. the mag you just unscrew remove and install the new mag.

The smoke has permeated the works, so a more aggressive cleaning will be needed.

There are many good suggestions for cleaning and deodorizing microwaves here.

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

A burning smell along with a different sound (growl) USUALLY indicates a breakdown in the High Voltage Side. This is not a direct short (short circuit) or the line fuse would have blown shutting everything down. The High Voltage Side is made up of-- The Secondary ,or High Voltage Side of The High Voltage Transformer, A High Voltage Diode, A High Voltage Capacitor, and The Magnetron. If The High Voltage Transformer is the problem it will smell like a florescent light ballast burning, and will smell each time you turn on the MW. A HV Diode burns and opens, thus no more smell. A HV Capacitor usually does not burn nor does the Magnetron. There is no Cheap-Fix unless you can see that the HV Diode is burned into and you can get to it to replace. CAUTION: Always unplug from power before attempting to repair. NOTE: If you replace a Diode make sure it goes back in the same direction it came out. Yes there is a front and back.

Time to buy a new microwave as it sounds as if the control panel is defective. A new control panel for this micro will run about 95 to 120 bucks + labor depending on where you buy it. I happen to like slightly burnt popcorn as well!! Nothing wrong with thats, as they say great minds think alike.