Microwave Problems Panasonic NN-S541 .... comes on, runs for about 3-4 seconds and then shuts off. Doesn't matter what cycle I choose, I get same results. I do hear some "strange" noises (clicking??) coming from the right-side middle to rear of the oven the short time it's running. Also, I get a VERY faint odor akin to electrical smell. It is so very faint as to make me wonder if I'm imagining ... it's that miniscule. I only paid $100 for it new, so I'm not wanting to take it to a repair shop ... thought there might be something I can handle. If not, I'll buy a new one. Thanks!

Panasonic NN SD696S (SS) popout knob style (Costco): Clicked off; first occasionally, then frequently, then always after couple seconds (click from relay on circuit board behind keyboard). Checked fuse solution--too sad--not the problem. Checked Fan and various areas with VOM; then noticed browning of the two connectors on micro-switch by door-interlock?. Switch (marked Omron V-15G-3C25, 15amp, 125-250VAC). Inside points showed bad arcing, hence the heat to char the connector insulation. Bypassing the switch, the microwave works fine--Eureka!--which will do until replacement. Found Grainger has (w/o min quantity of 100), for $2.21 (2KRF8)--hope to pick up one Monday. Switch is kept in place by two plastic "toothed" fingers--should pop right back in if dimensions prove to be identical.

Sadly, this model uses an inverter to produce high voltage instead of a transformer. While an inverter (switched-mode power supply) is more efficient from a power consumption standpoint, it is more complex, thus more statistically prone to fail. Even worse, the machine-soldered connections in a microwave inverter are often too weak, so they eventually fail - often catastrophically. (Thus the clicking and the odor, which is thinned out by the cooling fan). Manufacturers generally do not encourage or assist technicians to repair microwave inverters. They offer the inverter as a whole assembly, and they are not cheap! Personally, I would never consider getting an inverter-powered microwave repaired unless it were under warranty or a very expensive over-the-range type.

The same thing happend, twice, to my Panasonic model #NN S654WF. It runs for approx. 3 seconds then quits. No smells or other with this one, just the 3 seconds and cuts out issue. Unfortunately I a have a 10 year warranty on this thing, so I will have to put up with the 9 week turn around at the repair shop for them to order the same part and install it. It's a $21.43 kit part. Panasonic Part Number: F690L8F00AP for this model says it is a 1.2 CFT INV/FAN KIT (A). I know this is a year-old post, but someone who might be experiencing a similar issue might order the inv/fan kit for their model and install it faster and cheaper than a busy shop might?

Dont buy panasonic I have 2 and they both went just after 12 months with inverter failure.

BUY SHARP

Panasonic NN-SN778 Inverter type Genius Microwave. Bought from Walmart about a 14 months ago.
Microwave worked well and one morning, it stopped.
Whatever program is selected and then Start is pressed, the microwave seems to start, without the magnetron or Fan noise, then after counting down 2-3 secs on the display, it just returns to the Main menu (basically returns to displaying Clock).
The heat program does not continue and nothing is heated in this time. Seems to have decided to auto-turn-off itself.

I looked at this forum, many others, and played around myself. Checking components for basic function, resistance, continuity one by one.

Warning: Microwave tinkering should be done very very carefully. Due to high voltages stored in capacitors even after Shut-off, there is risk of fatal injury. If you are not trained, it is better to find a technician or go buy another microwave for close to $100, instead of risking your Life.


I retested after each exam of boards, components. Finally found a door switch that was slightly flaky. My multimeter would sometimes not move at all when the micro-switch was pressed. Sometimes it will work normally. I was looking for a replacement of this switch:


V-15G-3C25-K by Omron
Panasonic Part# is J61415G10XN

Found it at DigiKey and Mouser and many other places for about $2.
If you buy it as a Panasonic Part, then it is listed on other sites for upto $15.
While still shopping, I also cleaned up the micro-switch contacts with a file, and tried to work the push button many times with an air spray. My son even spilled some water on it when I was away.

When I put back the microwave with the same original switch, everything started working. I have given up on ordering the replacement part until it fails more definitively. Right now the microwave is working for the last 4 weeks.

Note these micro switches sometimes also just get dislodged from their anchored position, or some holding clip is loose. I am just not sure what happened, but I did confidently narrow the problem to this $2 switch.

It is not an encouragement for you to play with the microwave if you are not tech/electronics handy. It is extremely dangerous to open the hood.

-Irfan

It could be as simple as the cooling fan is stuck and it's shutting the oven off as a safety measure. Unplug the unit, remove the cover and see if the fan rotates easily by hand. If it does, look around for anything which looks burnt. I have one on the bench at the moment which suffered a burnt out microswitch on the door safety mechanism but it really caused a smell. If the fan doesn't rotate freely use a little wd40 (penetrating oil)and keep turning the fan until it's free. Then a little drop of machine oil and away you go. If that fails I'll repeat previous advice "Buy a new one" BMW PS microwave ovens can give off all sorts of funny smells depending on what's been cooked in it before :-)

Inverter type oven uses IGBT transistors and these are very sensitive devices and prone to failure.This may be the cause. New circuit board will cost around 100 bucks with trade in your old board.

Buy a new one. It doesn't worth to deal with it !!!! Good luck with the new Microwave !