#-59 - How to Test Microwave Door Switches

Does your microwave give you an “open and close door” error? Does your microwave count down without cooking? Does the turntable turn when the door is opened? How to tell if a microwave door switch is bad. Four most common ways that microwave door switches fail and how to test them. #testdoorswitch, #microwavedoorswitch, #microwaveswitches, #microwavecountsdown
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[@alanross3435]

New sub here…you nailed it showing the discoloration on the switch leads! New switch should be here tomorrow! We almost ordered a new one @ 160.$ out LG is only 10 years old! Thank you very much!👍🏻☮✌🏻

[@CeceMA05]

Very informative and detail! Thank you!

[@trinityappliancerepair1344]

Great video

[@TheTechCircuit]

Thanks!

[@sernani99]

Good info, I'm not the most handy with electrical components, I believe I need the door switch replaced, but I don't know if I need the normally open or close. When I start my microwave, it trips my circuit breaker. Can you please tell me which one I need, please?
Thank you.

[@jonnelson6448]

This is a very helpful video, thanks. Two questions:
1) Do you have a suggested source for buying new switches?
2) Is the problem sometimes a mechanical problem with the latch mechanism?
About 2), we've had the problem that the microwave turntable and heating turn on only if we tug slightly outward on the door. A few months back, I did check the electrical function of the switches, finding them fine, but I've not heard of anyone having to pull on the door to get the microwave to heat. (No error message, and the countdown display turns on and runs--it is just the turntable and heater that require pulling on the door.)

[@jefferson2310]

Not all door switchs click, some two prong side by side on panasonic nn cf microwaves don't make clicking noise, use of multimeter you will still hear the beep for on and off.

[@unamor]

What if the fan and turntable work, but the countdown won't move and food won't heat? Thanks for this great video

[@TheTechCircuit]

That sounds like a stuck relay on the board.

[@unamor]

@@TheTechCircuit Thanks a lot for your answer! Do you know of any resource on YT or else where I can learn to test and eventually replace these? Thanks again

[@TheTechCircuit]

@@unamor If you mean the relay - if shorted, it will read about 0 ohms from terminal to terminal (on top). However, replacing the relay can void the CE and UL certification of the board and I can't officially recommend doing that. Generally speaking, the generally acceptable method to resolve the issue of a fused relay is to replace the boards.

[@StockDude]

great video, thank you.....but my microwave is 27 years old and can't even get parts for it anymore! lol
An Emerson MW-8775S/D If you know where I can get some door switches, which is what I suspect wrong without checking it, then please let me know. Manufacture date June 1996. It still heats great.

[@robertburgess8981]

Great video! Will a heat stressed switch show an odd ohm reading?

[@TheTechCircuit]

Often times, it will.

[@robertburgess8981]

Thank you! We are trying to diagnose a problem on a Frigidaire microwave the switches don't seem to be getting made when you close the door. Sometimes slamming it worked but not anymore. All three switches tested good but one did seem to show some Blackness around the connections.

[@artriumph]

I have a GE microwave that powers on, the timer counts down, and turntable turns. However it doesn’t heat up. Could the problem be one of the door switches? I’d appreciate any help. Thank you very much.

[@TheTechCircuit]

If you don't hear it running, then it is likely a door switch. If it is going through all of the motions, it is likely the magnetron. In that case, I like to do current draw testing per this video: th-cam.com/video/fqb_ib7Hslo/w-d-xo.html

[@ryandrom7094]

Would 2 ohms when the button is pushed consider it a bad switch?

[@TheTechCircuit]

Yes if you touch the leads of your meter together and get 0 ohms. If your baseline is greater than 1 ohm or so the switch is probably good.

[@ryandrom7094]

Thanks! My baseline is 0 ohms and I'm getting between 2-5 ohms when the switch is activated. @@TheTechCircuit

[@TheTechCircuit]

Yes. I'd replace it. @@ryandrom7094

[@paul.alarner6410]

should a switch measure 3.5 ohms when closed?,if not does that point to it being bad?.

[@TheTechCircuit]

If you touch your multimeter leads together and the meter reads almost 0 ohms then yes. If it reads close to 3.5 ohms, the resistance is in the meter leads or connections rather than in the switch.