How To Easily Test Microwave Oven Parts! (Ultimate Guide)
ฝัง
- เผยแพร่เมื่อ 12 ก.ค. 2024
- How to test troubleshoot microwave oven parts, high voltage transformer, capacitor, HV diode, PCB power transformer, ceramic power fuse, micro switches(cherry switches), and magnetron.
**To purchase electronic test equipment and much more at a GREAT prices(Usually lower than Ebay), please refer to the link below. Be sure to BOOKMARK the link for futures purchases. Be sure to try the money saving coupon codes listed below. (Your purchase will support my work)
All Items: bit.ly/2cgYr14
Flash Deals: bit.ly/2cb6CZB
*Try these money saving coupon codes: affiliate6 or elec or elec1 or measure or microworld* or ask if other codes are available!
My other microwave oven repair video is here:
• Microwave Oven Trouble...
DISCLAIMER: This channel is NOT responsible for any injuries or deaths due to inept, careless, unqualified, or negligent individuals. If you do not follow my instructions carefully, fail to take necessary safety precautions, or doubt your abilities, then you have no business making any repairs to a microwave oven. Everything is at your own risk.
Thanks For Watching!
Support the creation of more electronicsNmore videos:
www.patreon.com/electronicsNm...
**If you enjoy watching my videos, please show your support by SUBSCRIBING, POSTING LINKS to my videos on other websites & blogs, rating a "THUMBS UP", and watching my video playlists. Doing so helps to ensure that many more videos will be released in the future. (Views are essential to ensure this channel remains in an active state)** - แนวปฏิบัติและการใช้ชีวิต
This is a truly comprehensive, methodical tutorial for people like myself who are comfortable working with electronics, but are unknowledgeable about testing microwave ovens. I have the top-rated, gleaming stainless steel, above-the-range GE microwave that quit heating after only three years and four months of use. Because of your video, I easily identified a shorted HV transformer.
(Prior to finding your video, I located two bad components: the HV diode and magnetron. However, the oven still didn't heat. A professional electrician tested the unit, failed to find the HV transformer failure and gave up.)
The Malaysian-manufactured unit is stuffed with Southeast and Far East Asian components. In sharp contrast, our 22-year-old Ohio-manufactured Tappen 1000w microwave oven continues to give top performance and trouble-free service. (I would pay the premium and buy USA, if given the choice.)
Thank you for producing an outstanding series of how-to videos, which are worthy of a college-level (or, at least, a good trade school) course in electronics.
Glad my video was able to help you!
electronicsNmore - Thanks so much for sharing your expertise & posting this video. Using your helpful tests, I was able to rule out the magnatron, high voltage diode & transformer. The high voltage capacitor tested bad. Replaced it & my old 1982 Sharp R8320 convection microwave started right up. They don't make them dependable like that anymore. THANKS AGAIN!!
Excellent video, Thank you for the detailed step by step instructions and component test info! ...I will definitely share the link with others !
Thank your for taking the time to make this troubleshooting video, it was helpful!
Glad you enjoyed the video! I have a lot of excellent videos on my channel that cover many different subjects, so be sure to check out my extensive video playlists for other videos of interest to you, rate thumbs up, and share my channel with others. Thank You
It was the magnatron. Installed a new one and it works great. Thank you very much for the great videos and the help!!!!!!
Good to hear! Share and rate Thumbs Up. Thanks.
Awesome video - thank you for making it and posting it on youtube!
awesome tutorials..thank you sir for sharing your great idea
I really enjoyed your video,Thank you very much.
my Q is after i found the problem in my microwave was the rectifying diode,when in stall right one mic was working but take to long than normal heating.
Thanks for very valued information about micro oven trouble shooting ,
I watch the previous video and what I have to say is that this video is fantastic and "electronicsNmore" know how to make good videos about microwaves. He is very detail and able to show how to test parts to people of any level of electricity knowledge. Congrats.
Agree with the fact that he is accurate enough, but not too wordy to confuse anybody. Very good videos indeed.
Great great videos! I'm reviewing at work and can't wait to go home and fix my KitchenAid microwave!
Good luck. Hope you fix it. :-)
I thank you for this information . I find it absolutely well prepared and very informative .
Glad you enjoyed it! I have many videos on my channel that cover a wide range of subjects, so be sure to look over my video playlists below for other videos of interest to you, and most importantly share. Thank you
th-cam.com/users/electronicsnmoreplaylists
QAq7774😊774😊4Q1~4⅞😊144qaaq11q11~a7😊71q 111qaa1\qAa~74a1~1a11q⅞⅞4😊😊😊⅞417😊14111771111😊😊4😊44a1177741😊7qqq1😊44147😊7q47😊😊😊744441qqaaaaa4444714147q1¹¹q 1q111😊Aaqq111111q1aq1Qqq14😊
your the best!!!...I just found out the problem of my whrpool microwave after watching your demonstrations...thanks a lot...your a good man not selfish, GOD BLESS YOU AND YOUR FAMILY....
Thank you! Be sure to share my channel with others and rate thumbs up.
this is the best teaching video, it is the best of all and wil be the best forever.
Thank you! :-) Please be sure to share my channel, watch my other videos, and subscribe.
A very informative tutorial. Many thanks.
Extremely Helpful Video,full of detailed information Thank You !!
You're welcome! Be sure to check out my extensive video playlists for other videos of interest to you, rate thumbs up, and share my channel with friends. Thanks
Excellent video. Very in depth and detailed
Thanks Joe! I have many excellent videos on this channel that cover many different topics, so be sure to look over my video playlists and most importantly share. Thank you
Thanks for a great in depth video. Very very kelpful
Glad you enjoyed my video! Be sure to check out my extensive video playlists for other great videos of interest to you, rate thumbs up, and share my channel with friends. Thanks
Excelente, lo recomiendo.
Very good videos about microwave fixing! Unfortunately my oven had a high voltage (5kv 0.7A) fuse blown which you didn't address in your videos (probably many ovens don't have one), but that was easy enough to figure out myself.
My symptoms were: Everything else works but oven doesn't heat. Lights, fan, even transformer hum was present.
After testing every other component I was suspecting some fault inside the magnetron even though it measured 0.3 ohm with an ESR meter. DMM showed below 0.1 ohm delta reading with leads shorted compared to connected to a magnetron so it was no help in my case.
I fixed mine temporarily with a 0.315A 1000v FF multimeter fuse for the next 2-4 weeks until correct size fuses arrive from china (1.1€ for 5 pcs).
I know that if the fuse blows now, the arc might not close inside the fuse because of inferior voltage rating and difference in construction. But I, a cheapass student, won't have a microwave otherwise so I take the risk of causing further problems with this cheap oven. :)
very helpful, thank you...
very good explanation this will help me a lot thanks
THIS IS BRILLIANT. EVEN THE THICKEST CAN FOLLOW THE DEMONSTRATION
TWO THUMBS UP 22-9 2015
+Michael Loftus Thank You! Be sure to watch my other microwave oven repair video as well.
This is the simplest instruction for us amateur fixers in my humble op.
Respectfully appreciate you for the information
Thanks, I will look for it.
Very good. Thanks
Such a good video, helped me fix my microwave
Very nice explanation👍👌
Thank you sir very nice explain
Great Video!
well explained bravo love your explaination,very informative video bless you.
Glad you enjoy them! Be sure to rate thumbs up and share. Thanks
Great videos,very helpful
Glad you like them! Be sure to share my channel with others. Thanks Fred
Excellent explanation of each test. You must be very good at what you do.
Thank you Paul! Be sure to look over my extensive video playlists below for many other videos of interest to you, and most importantly take one minute to share a link to my channel with others on social networking sites.
th-cam.com/users/electronicsnmoreplaylists
Your attention to detail is awesome, except my name is Raul , not Paul. Hahahahahaha. Its ok, i get that all the time
@@raiderman28 LOL. Sorry about that.
Thanks for sharing
very informative and educational thank you
+Ali Alywa
Glad you enjoyed the video!
this has been one of the best how to i have seen thanks for taking the time to share, is there a way to test the relays on the controlboard with out taking them off?
InstaBlaster...
Excellent for teaching
Glad you think so! Thanks for watching
Very good thanks
Great video thank you very much for your useful channel
toolman talal Glad you enjoy the videos. Please share my channel with others and rate thumbs up. Thank You!
It turned out to be the door switch. There are two switches in series. The mount on one swtich was broken so the switch shorted. Thx for your help.
Awesome video. Easy to follow steps. I have a GE countertop microwave that does not heat. Control panel functions fine. Fan runs. Light in oven comes on. Do not hear the sound of the magnetron kicking in. Followed your steps; i.e., door switches tested OK; relay on PCM registers 120VAC and then goes to zero when start is pressed. Magnetron checked Ok for ohms, however, the fins rattled when shaking the mag. Was able to push them together and eliminate the rattle. HV transformer, capacitor and diode all checked OK. I think it must be a faulty mag but is their any additional tests I can do before springing for a new mag?
So helpful; thank you. If one of my capacitor caps (the plastic) snapped, is it OK to still use the capacitor, maybe with some electrical tape holding the broken plastic in place? tia.
Thanks so much for this tutorial and forum. Defy Convention Microwave oven DM0357. Just went dead. Perhaps overheated. I don't know. Keypad dead. Should I replace capacitor first, or the keypad? Or, is it possible the keypad alone needs replacing. Multimeter testing showed components are ok. Have to guess if capacitor must be replaced and/or keypad.
This is an excellent tutorial, very clear to understand. I have a related question: you indicate to use a 18k ohms 5-10w ceramic resistor to discharge the capacitor; may I use a film resistor of the same ratings? Thank you.
Any resistor, just as long as the wattage/resistance value is close.
Great videos! If I have parts that are bad. Where do you get said parts?
Other units, or?
like your videos!!! so loaded!
+franse sishuba
Good to hear! Be sure to rate thumbs up and share with others. Thanks
Thanks for the video, it is the most informative guide I have seen so far. Excellent step by step instructions. I have one question. I am checking the step at 14:15 and instead of getting 95 ohm I got no measured value. Is there a way to further check the transformer? Thank you
No reading for the high voltage winding means a faulty transformer, or you failed to scrape away the clear coating on the transformer before touching the probe to the core.
GREAT VIEDOS! I LEARNED A LOT, THANKS!
Thanks Harry!
In my case it was the capacitor. Unfortunately it was the last thing I tested for I was afraid of the voltage thing. Anyway I did diode, magnetron, the little switches, those fuses and breakers first. One fo the 20A fuses was bad, replacing it bought the lights and display back, the microwave was turning but no heat. Anyway, when I finally get it off and check the capacitor, it was leaking oil and short. I just ordered one from Amazon and hopefully that's it. Thanks a lot! Will paypal some if the new caps fixes the issue.
Great Video thank you
+Michael Clayton
Glad you enjoyed it! Please be sure to share my channel with others and rate thumbs up.
Thanks
excellent
thnx man you are the best⚘
Glad you liked my video! Be sure to share my channel with many others, and look over my extensive video playlists below for many other videos of interest to you. Thanks
th-cam.com/users/electronicsnmoreplaylists
Hat's off...Vraiment Formidable...
Heureux que vous avez aimé la vidéo
Hi how do you check the thermal switches when you removes the wires sould you have resistance or should they be open when good?
excellent,thanks.
ismael abed You're welcome Ismael.
Thank you very much
+boss88 chang
You're welcome. Please share my channel and rate thumbs up. Thanks.
Thanks SO much--- saved me a lot o money!
Thanks for NO irritating bg music!!
At last a guy who knows what his talking about!
Geeeez! --- ther's a lot of aholes out there--- BEWARE!
Glad it helped George! Be sure to rate thumbs up, consider subscribing if you like a wide range of helpful and informative videos, and look over my extensive video playlists below for many other videos of interest to you. Taking one minute to share a link to my channel with others on social networking sites would be greatly appreciated. Thank you
th-cam.com/users/electronicsnmoreplaylists
Most interesting, may I ask ? can you not measure the voltage out of the output transformer while on to see if the transformer is working ie sending power to the magnetron ? and what would you expect the resistance to be on those same leads with a the machine off and capacitors discharged?
VERY dangerous! You need a special HV probe like I made on my channel. Or you can remove it after unplugging the microwave and discharging the HV capacitor and do as shown below. Do as shown at your own risk. It's very dangerous for the average person.
th-cam.com/video/VicnLpnwO-k/w-d-xo.html
Well, thank you for your videos. I tried to repair my Sanyo EM-V3405SW microwave (intermittent flickering appliance light when door was opened or during operation and pitch change in magnetron during flicker).
I was able to trace it to a relay, which I replaced (confirmed that it was relay by shorting the high voltage side of relay.
I ordered the relay, replaced it - microwave is running fine - but display is blank. Is there some video you have on testing LCD display operation ?
I will admit, I had disconnected the front touch pad ribbon that goes into control panel, when I was testing relay operation. Problem is I have no schematic diagram of the control board and have no idea how the display gets lit.
Hello,
I have a dead microwave. The light works when you open the door, but no display nor do any buttons work, fuse is good. I have narrowed it down to the PC Transformer according to your very interesting and informative videos. How do you remove it from the board for testing? Thank you.
Thanks for the video.
I have tested all the switches, termal switches, fuse and all good. Everything is working except heating. There is no 120v on the entrance of the big transformer hence no charge on capacitor. What could be the issue?
Outstanding video. Very detailed. Thank you for your effort. I have a situation and could use your expertise. I have a Kenmore Elite over the range microwave. My Son heated up some grub late at night and my wife came in in the morning and heard the microwave humming and could not shut it off. she pulled the plug and plugged it back in and everything was fine except it would not heat and would make a weird noise when she would try to use it. I took it apart and found that the Magnatron cooling fan shroud was melted and would not let the fan turn (ie weird noise). I cut the shroud from around the fan; put it all back together (to see if everything worked before ordering new parts) and everything works fine except it doesn't heat. My conundrum is:Should I even try to repair this? The only reason I can think of that the microwave was running when she woke up is that the filter was so clogged (didn't even know that there was a filter and has been there for 6 years caked in grease) that the system couldn't cool itself; the shroud melted, stopping the fan, which was getting a signal to cool the Magnatron. Which put it in a loop (glitch). Wouldn't even be wasting your time; but this is a very expensive microwave to replace and it's too cool. :) .Everything on the inside looks brand new and is probably the thermal switch that tripped but wanted your expert opinion on this before I started. I guess I would like to know if you have heard of "anything" like this? My problems are "never" easy. Thank you in advance for any help. Mark
Mark Schneider You need to test the parts according to the video. Not much else I can suggest. I have 2 videos on this subject. If everything tests OK, then replacing the magnetron is usually a good idea even if it tests OK.
electronicsNmore Any good leads on where to get a good cheap Magnatron? Amazon, Ebay or a better place? thank you, Mark
This is an excellent guide for enthusiasts trying DIY fixing of microwave.
One question:
If high voltage transformer primary tests 120 v AC on each terminal to ground, what does that mean?
That means your transformer is not connected to the neutral wire allowing it to turn on. The circuit is not complete. You have to trace the wire and find out why(there may be a faulty switch or blown thermal cutoff). If you connect a 120V live / hot wire to one side of the transformer, and the other side(terminal) is not connected to the neutral wire, then you wire have 120V on each terminal. If the neutral is connected, you will have 120V on one side(power feeding in), and the other side connected to the neutral wire to complete the circuit, will be ZERO volts.
Thanks For watching! Be sure to check out my video playlists.
Appreciate the videos, tremendous help. Lights would come on but microwave did not work. Replaced switch a d a thermocouple. Now everything works but exhaust fan turns on as sonn as I plug it in? I can switch speeds but won't turn off? Hope you can advise. Thank you in advance.
Bad thermostat(heat sensor). Make sure you installed the correct parts, and wired them correctly.
Once again, a really fantastic video. My only query is why don't you just test the diode with your meter ?
You can't test high voltage diodes using the diode test setting on a DMM. Thanks for watching!
Can the PCB transformer test be done while still attached to the board? Or do I need to de-solder the transformer?
What if i read 4.1ohm between the main connections of the transformer and 176ohm on the high V con and the body?
I've tested the capacitor and read 1.8ohm between the pins.
Thank you, I did test the capacitor and it tests normal I think at 9.37 for a 10 ohm capacitor and the terminal to body on each test infinity (followed your video). The buzzing is coming from the transformer. If I unplug the magnatron the tranformer still hums but the loud buzzing stops. Left the magnatron unplugged disconnected HV wire to the capacitor normal hum from the transformer but no buzzing. The tests of the transformer were all normal low side read .7 at 200 ohms and terminal to body was infinate at 20M ohms. High side .5 at 200 ohms and terminal to body was infinate at 20M ohms. The HV wire tested 91.2 at 200 ohms. I also tested the new diode and it was normal. I tested all the door switches, the thermo sensor, the fuse and transformers on the board all were normal. Again everything works except buzzing from the transformer and no heat, the magnatron is silent. I visually again inspected the magnatron, no cracks, sounds, etc... I also retested it and get .5 at 200 ohms and each terminal to body reads infinate at 20M ohms. Do you still think it is the magnatron?? and again THANK YOU VERY MUCH FOR THE HELP!!!
If you unplugged the magnetron from the transformer, then got only a hum and no buzzing, then that would indicate the magnetron is causing the problem. You need to swap out the magnetron. (0.5 ohms) for the magnetron is higher than normal.
Useful video thanks.
I've done all the tests but for the diode (as I lack a resistor) and PCB transformer (which I assume to be ok as the display works). The microwave comes on and the display and light works etc, it just doesn't heat the food. I suspected the magnatron but it checks out ok according to your tests. As do the fuse, door switches and capacitor. The only discrepancy I have is the main transformer, the primary windings are at about 2 - 2.5 ohms between the terminals and the HV Power output lead about 160 ohms to the core.
Do I have a transformer issue?
The diode can be tested w/o a resistor if you have a DMM that has a 50M or 60M range. How many watts is the microwave oven? You are positive the DMM is working properly?
Ok thanks for posting this video!! Question for ya, my GE microwave everything works but it does not heat and the turntable does not run! When it did this both stopped at the same time. Everything else sounds like it is running normal. What could cause both of these to go at the same time? Seems that they are not connected as far as what controls them or powers them. Even the display is still normal! PLEASE if you have any suggestions let me know! Excellent video just thought I would ask in your experience what could cause the two problems at the same time, so far I checked door switches and figuring out your instructions on checking the diode.
Sounds like a faulty door switch, OR when the door closes, contact is not being properly made to trigger a switch. Test each switch according to the video, and open/close the door while you test to ensure they are being triggered. POWER OFF!(unplugged)
great video but i think you missed the relay, i will try door switches in the morning but i am close to giving up, putting a new magnatron wasnt a good idea in the end a new micro wd have been better
The best!!!!!!!! thanks a mil
Thanks! Be sure to share my channel/videos.
Awesome!
Thanks! Be sure to check out my video playlists as well.
Thanks for the useful video. My microwave display is not working (door + light is working and tested fuse is fine etc). I checked and the problem seems to be either with the small transformer on the display-board or the entire display board. For the small transformer(on the board), on the primary I got 125 ohms. And on the other side I get 1 ohm and 4 ohms (the video mentioned about 400 ohms for primary and 8-10 ohms on the secondary). Do I need to replace just the transformer or the entire display board. Thanks for your response.
First unplug the microwave. Next discharge the capacitor. After that, remove the blk/white wires connected to the primary side of the HV transformer coming from the larger relay on the PC board. Cover the terminals with electric tape. The purpose of doing that is to prevent the transformer/magnetron from powering up when you plug the unit back in to test the pc mounted transformer. CAREFULLY test the output voltages on the PC mounted transformer while the microwave is plugged in. Wear latex gloves to be safe. No need to press start on the oven. you should get around 12VAC on one set of pins, and around 6VAC on the other set of pine. All pins are on the same side of the transformer in a straight line. If you do not see that voltage, then the transformer is faulty if you see 120VAC between the two pins on the opposite side of the transformer.
Thanks For watching. Be sure to share my channel and rate Thumbs Up.
Thanks for knowledgeful and helpful video. I need your assistance to resolve issue of burning fuse when microwave put in operation. checks on hv transformer, capacitor & diode found good.
Resistance on PCB on L and N terminal found 1424 ohms which seems not normal. What may be cause please guide. Thanks
I only upload well explained/helpful videos and answer simple questions. I don't troubleshoot for viewers. I already spend way too much of my free time helping people, and get very little in return. This channel is underfunded. Watch my other microwave oven repair video below for more help. Thanks
th-cam.com/video/t1tdj3OnlXU/w-d-xo.html
Thanks for uploading this was so helpful! While testing the transformer, the resistance between the single high voltage wire and the body of the core did not change the reading from OL. Does this mean the transformer is broken?
Place the digital meter on a low ohms range(up to 200 ohms or 1k ohm) You should get a reading. Be sure to scrape the transformer core in the area you test from. There is an enamel coating which must be removed to expose bare metal prior to testing.
Thanks for watching. Be sure to rate Thumbs Up, and share my channel with others.
electronicsNmore That did the trick! It was reading 154 ohms. Thanks :)
Awesome video, still have problems. Micro would buzz, but would not heat cup of water. Power setting button did not work, everything else did. Replaced Diode, set power to 2, fired it up, and fuse blew. Replaced fuse, turntable, fan etc. ran with transformer unhooked, all was O.K. until Transformer was connected, fuse blew again. All test readings on mag, transformer and cap are same as yours. Ideas? Also, can I wire a 20 amp household breaker in-line to test? Blowing ceramic fuses is getting expensive!.
Fuse usually blows if a door switch is misaligned or faulty, the cap is faulty, or the magnetron is shorted. Thanks for watching!
Everything checked out okay on my microwave according to your guide on oven parts. But my 1st instinct was the Magnetron went bad but has 0.1 Ohm resistance which you said it is good (0.1 to 0.3 ohm). I put on heating and I can hear humming but no heat. Any suggestions? Thank you for your informative videos though.
Very likely if the diode and capacitor are both good. Sometimes a magnetron can test good, but be bad. Did you measure the resistance from each terminal on the magnetron to the metal chasis? You should not get any reading. If you do, it's bad. Use a high ohms range on your DMM.
Thank You For Watching!
electronicsNmore I follow your guide and I didn't get any reading for touching metal chasis and one to the terminal. If I have another magnetron from other microwave can I hook it with the one that's not heating up to test?
If the size is similar(wattage), and it bolts in the exact same way, then yes. Substituting another known good one, will let you know if yours is faulty.
Magnetron doesn't have any wattage on the label. How can you tell the wattage?
Go by the label on the microwave oven. 900w /1000w...etc.
great video i have a combination of microwave and oven GE PT970S M2SS do you have any literature/information how to take the micro apart to see the components. I have no powers to the micro
+Antonio Pacheco
Probably a blown fuse inside the microwave due to a faulty magnetron, capacitor, diode, or door switch. You need to take the time and do some research on your make/model microwave.
Thanks
Thanks a lot for your video. It helped me isolate the fault to what I think is the diode. This is a Kenmore Elite , about 6 years old. My problem is that I cannot find the diode it is using. It is marked CL04-12. I had to settle on buying from eBay and I bought three of them. When I replaced one of the new diodes in the microwave I still hear a loud hum.
When I disconnect the magnetron the hum reduces substantially. Everything else is working, lights timer, turntable etc. The capacitor checks out at 1 microFarad.
I suspect I got cheated on the diodes.
The new diodes show 15 Mega Ohms in one direction and over limit in the other. I am using a Fluke 87v DMM.
What else could be wrong? The magnetron also checks out as per the tests.
Thanks for the videos.
I've read your comments and I think I have a puzzle.
The puzzle occurs when heating more than one batch that needs heating. The first batch heats fine. When we heat the second batch it takes longer. Everything else is fine. Please suggest any possible solutions. Thanks
Sounds like the magnetron is failing. You can try testing/replacing the capacitor/diode. You may also have an issue of burned relay contacts not allowing full current to the HV transformer.
I have watched your videos and they are helpful but I have a question. When testing the hi volt line on a GE transformer in our microwave, I get a reading of 76.5 on the high voltage side. Is that acceptable as you have mentioned 80-120 is desirable (you got 95.5). All of the other components have checked out as you mentioned and we did replace the diode but it still makes a loud humming noise and does not produce heat. The GE Profile Sensor convection microwave oven we have is 16 years old.
That's fine.
@@electronicsNmore well then the only thing left is to replace the magnetron because as you noted they can test correctly but still be defective. Your opinion?
I have a Sharp microwave oven. Everything works except the digital display, including the clock of course. Any tips on the problem and how to fix it. Thanks in anticipation. I like this video. Very precise and clear.
ron martin Mhg Sounds like a faulty LCD display or faulty conttol board.
Thanks for the advice.
Thanks for the proper, safe process. Interestingly, about half the folks DON'T test for shorts on the Mag (terminals to body) which ultimately was my issue as I was seeing continuity from terminal to body. Just received and install the new Mag and it tested out exactly as you specified .001-004 ohm across the terminals and OPEN from terminals to body and my unit is cooking again and operating quitely (comparatively speaking), it sounds like new again. I do have a few questions maybe you can answer as I haven't found anything yet on the subject: 1. can a shorted Mag be repaired? The terminal block looks clean, so it must be an internal short and 2. As far as the part # mine is an LG 2M246 050GF 1200watt and there is an additional set of letter/numbers under model #. Is the main number I need to worry about the 2M246 or are any of the other numbers important to match? Thanks again!
Not worth the time repairing, you can buy a used replacement on Ebay at a low cost. Thanks for watching! Be sure to share my channel with others.
@@electronicsNmore Will do! KUTGW!
Hi , you could also test the diode with a 9 volt battery since our multimeter tester cannot supply enough power to elicit a reading
For a reliable test, higher voltage is best.
Hello,
I have one (few yrs. old) Kenmore micro, and the fan, light, carousel runs continuously until I open door. Heating cycle does run and cycle fine with touch pad, and heating does go off when timer zeros out, the rest just continues to run until door is open or I unplug it. I have a feeling there is another relay on keyboard that is stuck in the closed position for the light, fan, and carousel cycle! It did this recently before but cleared up and now doing it again full time. Do you suppose this would be the be the case?
I wouldn't be asking if weren't mounted under cabinet..
Old tired electrician...
I'm trying to figure out the specs on a magnetron that is no longer available so I can replace it with a non-oem unit. The original is a Sanyo 2M219H which, from what I've read, is a 4.1kv rated unit (due to the "2M219" part, H being the physical size and layout of mounting ears, vents, etc).
The problem is the tag on the oven itself says "microwave output" is 1000w which, if I'm not mistaken, would be equivalent to a 4.35kv rated magnetron. So I guess my question would be: can, would, or should the oven and the magnetron each have two different output ratings, or are they one in the same?
Thanks for any info.
I have a ge convection microwave. When I open the door the humming noise comes on and turn table turns is this the microwave shooting microwave at me or a fan running. microwave does warm my water in the cup. The only thing still under warranty is the magnetron should I throw microwave away or call repairman
Great Video. How do I check when my turntable motor does not have 120V input power? I test the motor with 120V source and it works but there is no power supply to my motor.
Trace the wires. Could be a faulty relay.
goodl talk. But Blue letters are difficult to read where there is no enough light.l think white letterട are So good insted of blue letterടThanks for your great work-
Yes. I agree. I switched to a different method 5 years ago. Thanks for watching!
Great Work!!
My GE microwave oven blew the internal 20A Fuse as it started to cook. Replaced fuse, set the time, hit the start cook and it ran for a second and the fuse blew again. Took it apart. Door switches seem ok. HV Cap seems ok. Read the right capacitance with my digital meter.
HV Diode voltage test with 9 V battery passed but I don't get any voltage if I measure resistance in either direction! Shows open either direction.
The magnetron resistance tests come out fine but if I shake it, it has a slight rattle noise!
Checking the internal light of the microwave found the light bulb to not be seated tight.
Any thoughts/comments what might be causing the 20A to blow?
Thank
vj K Testing the diode with 9V is no good. You need much higher voltage as stated in the video, or a meter that has a very high ohm range of at least 50M. Use your car battery with the engine idling. The usual culprits are a faulty capacitor, diode, and lastly the magnetron. If you can rule out the capacitor and diode, then swap out the magnetron. Make sure the HV transformer passes the tests.
Thanks For watching.
what if the rsistance of the primary of the transformer reads 2.5 ohms? is that good or bad?
I have 120V on the HV primary, the light comes on, the turnbtable rotates but no heat. HV transformer primary is 0.4 ohms, secondary winding is 90 ohms to ground, however, the HV secondary connector unplugged going to the magnetron is 0.3 ohms. Is that a secondary winding short? Do I need to replace the HV transformer?
Hey Mike.... Great video!
I'm looking for some advise before I can even think about trashing this older but expensive 1650 watt GE built-in oven.
I get the annoying buzzing BUT the oven does still heat at what seems to be it's normal heat rate.
Here is what I did so far.....
1.I did ALL the magnetron tests in your video. All tests were normal EXCEPT when testing across the 2 terminal plug on a 250 ohm setting, I get a reading of point five (.5) This is also the exact same reading I get when I simply touch only the 2 probes together. Does this indicate that there is a short since .5 is my starting resistance due to the resistance of the meter and probes itself?
IF yes, I do not see how the oven would still be warming! I also tried 2 other cheaper meters and each said resistance was one point zero. (1.0) Again, both meters tested at 1.0 when only touching the probes together. (Again I assume this is because of the normal resistance to the meter wire and probe itself and the meter just not being 100 percent calculated)
Do you think I have a full short in the mag based on the above reading?
2. Next, I ran ALL of your TRANSFORMER test. All were ok EXCEPT on the high power wire test I got a reading of 79.5 olm on my good meter and 80 and 79.5 on the other two cheapo meters that I have. I believe that you said between 80 and 140 or so was most common I am at the extreme low end or below....so could that be causing my BUZZZZ?
3. I also tested the cap and diode test. Both test were good. (did a test using a 9v battery for the diode) Both of those test we ok as I expected.
4. I removed the mag. Shook it. No noise. I also carefully looked for cracks and any burning on the head. The silver thingee that surrounds the head of the mag was nice and shiny silver but there is some kind of metal thing inside of that shiny silver part that was black.... but i assume that is normal....right?
5. I can not tell if the buzzz sound comes from the mag or transformer. I disconnected the 2-wire terminal plug that goes into the rear of the mag. When I turned the oven on, i did not hear any buzzing, but of course there was no heat :) I would guess that might not tell me anything since I assume that pulling out the mag might also stop the buzzing even if the transformer was bad and causing the mag to buzzz.
Any thoughts or questions would be really appreciated Thanks!
+MrUsaer
Hi there. I'm Doug. :-) 80 ohms on the HV secondary is fine. You can unplug the unit, discharge the capacitor, then unplug the red HV wire from the transformer leading to the capacitor and leave it sticking out and away from the metal chassis. Plug in the oven, stand away from the open areas(danger areas) of the oven, and TOUCH NOTHING except for the control pad. Enter 10 seconds and press start. See if the buzzing sound is gone while the oven is running, if it is, then you likely have a faulty magnetron even though it tests ok. Unplug the oven, discharge the cap again to be safe, then you can touch things.
It seems to me that MrUsears is having an issue with the mica lid that covers the openning of the waveguide in the oven cavity. Thanks for your video.
@@juanabreu5127 What can go wrong with those mica covers? Just curious.
Microwave capacitors will usually have built-in resistors connected to each terminal so that the capacitor will discharge automatically when the oven is switched is not in use.
Yes, slowly discharges with the internal 10M resistor. Thanks for watching!
great video! i just want to findout, what causes my microwave oven to just stop working and display zero on display? nothing else moves no humm nothing. just a lit display displaying zero.
Does not sound good if the keypad/display is not working. May be a faulty main board. Try pressing clear, and as a last resort, leave the microwave unplugged a few hours and try it again. The zero may also be a trouble code for your oven. You need to do some homework.
Very good instructions. However, can I suggest you to add a test for the transformers low voltages ? You should test if there are no short between the secondaries.
The circuit board mounted transformer?
Yes, the little ones. It could happen, sometimes, that because of a default on the board driving to a peak of current a hot point between the secondaries. This is valid not only for the microwaves. You can use the mutimeter to perform the test. In case of any doubt, you can drive direct current into each secondary with your external source and test the other secondary from its two ends and, 2nd test, one end of it to the two ends of the first one under DC. Repeat this with the second end of the secondary considered. In fact, it is an insulation test between those secondaries to perform.
Canl you make a video repairing a turbo broiler including a circuit diagram tnx
I used your procedures to measure magnetron resistance and initially got 0.3-0.4 ohms but value gradually fell to zero. Is this a failed magnetron? I checked HV transformer and got good primary, but lower pair of HV leads measured zero ohms. Single HV lead was 87 ohms. I used a 20 megaohm, auto ranging VOM.
The magnetron should read close to zero ohms, but never zero. The test is also not 100%. Shaking the magnetron should result in no rattling, and the 2 ring magnets must not be cracked. There is a 2 turn winding on the transformer(red wire or red w/white) which measures close to zero also. That is normal. That is the filament winding.
Thanks For Watching! Be sure to share my channel with others, and rate Thumbs Up.