I changed the Cap and the diode because they were cheap so I just did it to start out and of course they weren’t the problem. The door switches, HV power supply, fuse, cap, diode, thermal protection switches and magnatron all tested fine though I did notice the metal on the magnatron “gun” or the emitter looked cooked. When I tried cooking the magnatron gets really hot but the food stayed cold. I bought an over the range used microwave for $20 and tore the magnatron from that machine and put it in my far more expensive all stainless machine and made it fit with modifications so it would mount and stay in there and now the microwave works perfect. My microwave has a built in convection oven and cost a lot of money when we bought it so I really didn’t want to replace it with a walmart junk o wave if I could get it working. Your video and videos from other youtubers really took the mystery out of my microwave.

Very useful explanation. I am confident now to experiment with my microwave oven which stopped working due to power fluctuation/high voltage in the mains.

Learn something new everyday, high voltage fuse has a spring to pull apart for breaking the arc. Great information!

thank you, I am following, from Tanzania. I usually watch your videos then I go around the streetcars to practice then they pay me.

i really appreciate the video you made ,it is quite clear,one thing i need to ask is when we change the power levels of the microwave we are normally playing with the duty cycle ,which for example if we need 80% power we are switching on the microwave for 80% of the duty cycle and make it off for 20% of the cycle and make this repeated till the set time is elapsed, do you think it is possible to vary the input voltage of the primary transformer and get different levels of continuous power ?

Detaching the relay connector and putting in the wire in it was a great tip!

i like the video, it helps me understand a lot.i have one thing to ask ,normally most of the time as i observed most of the magnetrons are supplied with a 3 to 4V Ac and up to 10 A current flowing through the filament. what will happen if the supplied voltage to the filament is increased or decreased? what makes the microwave output power high or low ?is is the filament voltage variation or the high voltage side variation ?

Hi Susana thank u for taking the time and effort to make this video. If we have to replace the transformer or HV diode or the capacitor can we use ones that are slightly higher capacity? From uk

Thanks, nice explanation, What causes the windings of transformer get burnt please?

hi sir,i hve question,what type or kind of fuse is that with the spring?very thankful for your answer..

Thnks for the lesson..I have a DAEWOO microwave and it dont work at all...it has"" NO power" at all the capacitor is good the thermo sensor is working...the inside light works... it has one 20Amp/250vlts fuse its not bolwn the 3 door switches work..""the transformer is not getting power"""I check those components individualy with multimeter ...what can it be??? Can you help me???

Wow I really love this over here, thanks for the video

Thanks for your very helpful video!

OMG, at 08:40 I got goosebumps, and at 09:52 I totally freaked out. I didn't even look further, I saw enough. On a 1.2kw device, such a thin wire with a loose contact gets so hot that the plastic coating melts, and then you touch it with your bare hand? Bravo! Are you aware that kids watch things like this too and someone could try this the same way tomorrow? Maybe with a little less luck than you had? Your video shows irresponsible behavior that poses a serious life-threatening and huge health risk.

Very informative and professional

The most useful video! Thank you very much!!!!!!!!!!

Hi sir...very helpful.. you can continue by remove the relay and check it outside to confirm the fault is by a relay...

My g.e microwave heats up only issue im having it doesn't show no #'s on display,could it be resister,transistor or a capacitor?

If the mains fuse is blown, the door safety switch could have shifted out of position, either due to plastic cracking on the switch mount or shifted from slamming the microwave oven door. It's a safety feature, acting as a fail safe to prevent the microwave from powering the magnetron with the door open.

Excellent explanation!

very informative video! 👍

Awesome tutorial n tutor

Would it be easier just to take off the plugs off the capacitor just to avoid any high voltage or injury?

This man certainly knows his stuff. That said, his instructions and physical demonstrations (especially) are flawed. He takes a lot of liberties which work for him, but can result in injury or much worse for someone who does not know what they're doing or doesn't realize that electricity CAN kill. Several of the components within the microwave oven carry enough voltage/amps to do just that. His use of a watt meter in the first test is novel. It clearly shows something amiss. Again, however, most people can figure that out somethings not right by knowing the appliance is not working properly. Such as not heating foods or liquids or intermittent operation.

Very helpful thank you

Very good video, very informative. Mine was door micro-switch problem. But after replacing the switch in my "under the cabinet" Whirlpool microwave, it was not heating up. Forgot to note the wiring before removing it and connected it back wrong. HV transformer primary was not getting AC power from relay because of wrong wiring. As per video, I checked it step by step to isolate the problem and fixed it. No prior experience with microwave repair :).

I have Sharp -888F oven. Food is not heating up by microwave. Grid convection all working fine. As given in several websites, I tested using Multimeter the Fuse, Door switches Capacitor HV Transformer and Magnetron. All sounds working. Even I am getting 220 V across input to HV transormer when select Micrwave instant heat button. Please share remedy for this issue…

hello thanks for your video very helpful I have a question My problem is the magnetron is burn am I have to discharge the capacitor before I replace the magnetron ? or I just replace it and that's it ?

Hi, My microwave takes 1 hour to power on. Any iadvise what might be wrong. I changed the fuse. Still same probem. After it powers on. It works fine. When I turn power off and back on within 30 seconds, it turns back on immediatey. But when it is off for 5 minutes or more, then I have to wait for 1 hour after I turn switch on before it powers back on.

Can you put diode on any terminal of capacitor

Nice thanks for the info!

Do you have Part 2 Covers repair of the control board?

Hi..mine microwave can on only 20 seconds then off? what u reckon is the problem? Thanks

tX FOR video. So, I have No power to unit, seems totally dead. I did put a burger wrapper in by mistake, as you said, and it caught fire, then she shut down. But that fuse is fine, the thermo switches are all good, door switches all good. I have 120V to the fuse board, fuse has continuity, 0V AC & DC on blades that connect to relay, relay has no continuity .... then ... 12V coming out one side of transformer, 0V out of other side of transformer, .007 volts AC on capacitor test, 0V DC.... I can't figure it out :(

Thank you although this is very dangerous

Next on How to Destroy a Multimeter: discharging high voltage caps through the current range. News at 11.

Sir my microwave keeps on all time but no heating. When I open door then it turns off. When I press keypad start button it works to heat. But won't stop unless I open the door. What should I do?

Thanks it s helpful

There should ba away to measure the secondary power from the transformer

Sir penasonic ka microwave hai jo 2 second chalne ke baad band ho jata hai kya problem hai sir please

please what could cause a microwave blowing fuse when u turn it on

Good video, but it is not dangerous to test your microwave without the cover ? Because radiations from magnetron could hit you during the test

Grill is working but micro not working what is problem

Good

You do not use multimeter to discharge a capacitor like that !!! Use a resistor to discharge it !!! Luck of knowledge can cost you your test equipment or your life !!!

sir, I've changed the fuse because it was unserviceable... microwave starts to work satisfactory, but after some days again fuse blows off... again fuse changed but now magnetron is not working... what should I do???

good post, i want to hear your speaking, can you add english subtitle..plyzzz.

Crazy, never do this, he almost killed himself at 9:50, the wire was so hot that the isolation melted away...

This man says it can kill you if you do what he's doing. Now that equipment is more expensive than the microwave he's working on. Just a new magnetron cost around half or 3/4 the price of a new microwave. Save yourself a mess.

You will live a lot longer if you firstly take that ring off, secondly wear rubber gloves and thirdly use an isolation transformer.

Please do not follow Susana - As an X RAF radar technician I can honestly say you are likely to get fried - Working with cases removed is a NO NO, unless you have shields present. You Discharge Capacitors with a Brinkley Earthing Stick. You always use crocodile clips to measure voltages and then switch off between measurements. And as another viewer has already pointed out. "Rings on his finger, bells oh his toes, he will bring disaster wherever he goes" - Don't give up the Day Job Susana

Absolutely unbelievable, why would anyone encourage people to A) Operate a Microwave oven with the covers removed & B) To work on a Microwave without any form of training. Never mind the Microwave radiation, the Voltages generated are Lethal.