You nailed my problem. After testing all the switches and finding they were fine, I was stuck. I knew it was a door issue. The problem started with opening the door while the microwave was running. I figured that quickly. Just don't do that and it will be fine. About a month later it just popped my breaker EVERY time. Your adjustment and all works fine again. Thanks for posting.
Excellent explanation - helped me resolve issue of fuse suddenly blowing repeatedly, yet all 3 switches are good. Found it was the door hooks had worn a groove in the switch housing so bottom hook was disengaging switch earlier than top switch - used some polyurethane 2 part adhesive and bonded a thin shim to rebuild and fill the groove
My microwave was blowing fuses when I opened the door. I thought it was the switch at first but it was operating normally though showing burnt spots on the contacts. I cleaned the switch and pushed back the plastic part on the top as you said and it's working again! I almost sent the microwave to the trash but didn't because of your video. Thank you so much for that little trick!
Oh my gosh! I watched those other videos first about replacing a bad switch. I was convinced that I should just buy all three switches and replace them all at once, that way they would all last a long time. Then I tried your suggestion about the right way to open and close the door and viola!!! It's works perfectly! Now I don't need to replace ANYTHING. Thank you!
Glad I read this before I ordered new switches. This did the trick on my Frigidaire and now I open the microwave from the top of the handle. Thank you!
This is awesome. I have a client with this exact same problem. This makes complete sense. I've already checked all 3 switches, amperage draw, breaker. This is the solution. Thank you.
Thank you for this. The sales guy from where I bought this suggested just getting a new microwave. Instead, after watching this, I pulled everything out, put it all back in nice and tight, adding the extra screw like you showed, and it worked perfectly.
Yes, this is the best door switch issue video. I don’t know why it has taken so long to see this. I replace the switches and the latch / switch holder and the fuse still blew so I bought a new microwave. I wish I would have seen this video prior to doing that. However the fuse would blow when the door was completely closed as soon as I turn it on. So I am wondering if it is indeed another issue with the unit.
Mine had the same switch "bad" (the middle one), but actually the switch was fine, no wear or malfunction, just bad mechanical design in that the door latch didn't quite press the switch actuator far enough. And of course no adjustment available. So I ended up drilling a very small hole in the center of the microswitch actuator and screwing in a #00 screw from an eyeglasses repair kit, thus adding about 1mm of height to it, enough so that when the door closed, the switch was activated correctly. Cheap design, a single DPDT switch with some mechanical adjustment available would have been the right way to go.
Thank you very much for sharing this video. I've been having intermittent problems with my OTR microwave. I replaced door switches several times now however, the most recent one didn't work even after replacing all 3 switches. It keeps tripping the breaker when I open the door. I tested all 3 switches and they all seem working right. I tried pushing the switch assembly as far back as possible and tried opening the door from the top and it worked. We have had this microwave for 7 years now and I don't believe in just throwing things away when they stop working. Thanks again and have a great day.
That was it! Thank you for the insight on that possibility, my microwave is 4 years old and it was tripping the breaker. I tested the continuity of the switches and had to replace one, it worked for 2 days then tripped again. I went ahead and used a small plastic shim on the top door insert, tightened the screws up and it worked. Only time will tell, hopefully my issue is resolved. Thanks again for the video.
Thank you! I have been chasing this problem for awhile now. It was spot on and totally makes sense. Saved me money and from throwing away a perfectly good microwave! Awesome
Super helpful video. Thank you. Unfortunately your bias trick wasn't enough to overcome the slop and flex in my GE PVM9005SJSS door. After biasing the way you suggest, I was able to fix the problem by adding a small amount of moldable polyester plastic to the face of the bottom pawl that actuates the interlock switch. The material, maybe 1mm thick, goes on top of the area where there is visible abrasion from interacting with the microswitch. I wrapped it around in a band so it would stay in place. There is enough clearance on the receiving end for the extra material on the other faces. I was careful not to put any plastic where it interacts with the bottom switch.
I've got two identical of these GE microwaves. One has the problem, the other doesn't. What I noticed is the door pulls harder on one that has the problem, which is why the "twist" happens. The other opens very easily and doesn't have enough stress on it to twist and therefore does not have the problem. So I'm going to do further detailed investigation, but I'm thinking it is actually a manufacturing defect or installation issue.
Really appreciate the video! Your video helped me get to an easier solution... I had read after hours of searching that the problem can be connected to the door latch itself wearing down. On my GE JVM3160DF3BB I tried the interlock switches to no avail, and then ordered the Door Latch piece part #WB10X32782 and replaced that piece and it worked perfect! I had the same issue where it would trip the breaker only when opening the door while it was running. You can see how worn the door latch piece gets! Mine was pretty worn, I had purchased it new 4 years ago so it has some mileage. It seems like replacing that part is only a temporary solution as I am sure this one will wear down like the old one in a few years. For anyone else wanting to replace that part, know that I did not add any screws or move that plastic piece like in the video.
This is the best video I've seen on this topic. I've replaced the switch on my Bosch mw for the third time and thought I'd get another year or so... This time the breaker still tripped after putting everything back together. So digging deeper lead me to this video. I used a plastic bread bag shim on the top of the bracket to rotate it back. Without touching the switches the breaker no longer trips. I think I've been lucky with reassembly in the past giving the impression that a new switch solved the problem.
The middle switch is the monitor interlock. I stared at this mechanism for about 2 hours before i fully understood where it failed and why. The problem is the lower ramp has a small groove worn from years of plastic on plastic. This causes the pawl to fall off the ramp before its deep enough to engage the monitor switch. No amount of twisting the bracket can fix the root issue. But there is a easy reliable fix and its free. All you need is a zip tie and super glue. I posted a video on my channel.
This common problem seems to have many solutions: switches, switch bracket, bias of bracket and on and on. Your solution worked for me. I also replaced all the microswitches.
I have no idea yet if any of the info in this video truly explains my situation since I haven't started diagnosing, but it's great that you point out how this can happen even if everything is fine, because I have my microwave over the refrigerator but the top of the fridge is a bit sunken so the microwave door scrapes the top front of the fridge a tiny bit. This means I often pull upwards on the microwave door to clear it, and now that it's tripping my circuit breaker, I wonder if it's possible that I'm the one who blew the microwave's fuse by making the latches unlatch in the wrong order!
Great video , explained perfectly, gave me the ooohhhh moment of what's going on and I can replicate the same scenario to test my alterations. 10/10 my dude!!
I changed the spring in the door controlling those two pawls to a weaker spring. I then had to ream out the switch bracket holes on the microwave and add some popsicle stick shims over the microwave switches to make up the difference lol but its been tested 100 times she works
It's close to midnight and I came across your video after hours of trying to find out why my switches were fine, but the breaker kept tripping. I did exactly as you suggested by adding a second screw, pushing the housing for the switch back and using a thick plastic tie to keep it pushed in. I've plugged the microwave in and voila, it works like a charm. I repeatedly opened and closed the door and there were no longer any issues. I was actually completing an order for a switch holder from Amazon before the magic solution so thank you ever so much. By the way, my microwave is the Frigidaire Gallery and the flaw with the door is exactly as you described it.
Thanks for posting. I thought i was going nuts as i to y would opening the door trip the breaker. All my fault, opening the door while microwave running. Laziness to hit stop/ cancel has now costed me hundreds of dollar😢
wonderful information! thanks! i changed out the monitor switch 2x and every time my son puts popcorn in the microwave, the breaker trips. I didn't understand why until the third time and now i believe vibration caused by the popping corn causes the door to vibrate/move in such a way that the switches no longer maintainthe correct position and trips the breaker. looks like this is more than just the switch, it's probably the door mechanism that's worn out. popcorn. i never thought :)
The one thing I'm not seeing in many of these repair/explanation videos is that you shouldn't be opening the door while the microwave is running. These switches are for safety. The reason full current is running through these switches is so that it can be dumped instantly when you open the door so you don't fry yourself. Always, always, always stop/pause the microwave before opening it and you should never run into this problem.
Thank you for this helpful video and narrative! Glad (sad) to see so many others with the same problem I had. At first, it started tripping my circuit breaker if I opened the door while it was running. Then it got worse and would trip if I started the oven (about 3 seconds, after the fan starts blowing and just as the magnetron kicks in). As a few others have noted, the latch board (which holds the switches) has two "ramps" that the door hooks "ride" up and over when closing the door. After years (7 in my case), those plastic ramps wear down and the top-most edge wears off unevenly, allowing one hook to fall before the other (causing the timing issue). I considered building that plastic back up but decided to just buy a new latch board (~$45 bucks, part# WB06X10610) as well as a new set of switches (~$10: 2xNO, 1xNC, for good measure) both from the online shopping A-beast. If you go this route, just remember to transfer the pawl/lever from the old board (near the bottom switch) to the new one (it isn't included). And be SURE to DISCONNECT THE POWER, of course. Also, check the glass fuse at the top front, behind the metal grill (125V 20A). So, about $60 after tax - still so much cheaper and easier than a service call, new microwave, or a DIY repair with melted plastic or glue (imho). But I agree - design flaw. Someone should 3D-print these latch boards and make a mint...
I am having a similar problem. I just wanted to clarify, even though you did not open the door when the microwave was running, you still had the problem? I always hit the stop button before opening the door but I am still having the blown fuse issue. I just wanted to make sure that you can have this problem even if you only open the door after you hit stop. Thank you so much for the info and help!
This is perfect for my Frigidaire, appears to be virtually identical. We replaced the fuse, it was fine, until a houseguest opened the door from the bottom while the unit was in use, without pressing stop first. Replaced the fuse again, it’s fine. Your insight that it’s a design flaw in the door is both accurate (so far) for me, and really helpful. Now I just have to get any visitors to follow the instructions. Many thanks!
I ended up attaching a very small shim of wood right under the hole for the top hook to keep the bracket angled back at the top. I also built up the bottom hook a little bit with some duct tape. It seems to have done the trick. Mine now operates as intended.
Einstein of the microwave! You must be an electrical engineer or self taught like Felix Wankel, father of the Wankel rotary engine. Solved my problem second time around.
I watched your excellent video but forgot to make your modifications when I installed my new switches and fuse in my Bosch 5000 series over the range microwave. I put a glass of water in and heated it for 1 minute. Opened the door and verified the water was hot. Then I put it back in to test how the stop switch worked hoping that pressing it would act like a pause so I would never have a reason to open the door with the unit running. It just turned the microwave off so that wasn't going to work. We would just have to remember how much longer we had set. So with the unit off I opened the door and pop. Fuse blew and lights off. That was a surprise. I hate to spend $629 for a new one with 10% of the reviewers complaining about blowing fuses so now I will try your modifications and test with a battery and oscilloscope so I am sure to catch the switch issue and can be sure once I make the mods that I am good to go. I was really surprised then the fuse blew with the microwave not running.
I finally fixed my microwave and in addition I know why it really failed. The way the design is done, the top switch disengages as soon as the door starts to open. It is triggered by the tip of the upper door latch. The monitor switch (the center switch) is triggered by the side of the lower door latch. As the door is opened, the latch slides out so that this switch can't engage until the latch is almost all the way up against it's spring. The problem is that as this latch rubs on the piece that holds the switch, it wears a grove in that part of the latching mechanism. As soon as the grove gets deep enough, the switch will activate because it is no longer being held against the switch if there is any twist in the door. I replaced the part that holds the switches. It costs about $10. With the new part, the door cannot twist and the monitor switch cannot activate. I also replaced the latch prongs as there was a small amount of wear there and that part was more expensive. I probably spent about $60 total what with having to buy the switches twice.
Thank you so much for the explanation and fix information. In my case the top screw on the switch bracket had worked loose. Per your advice, I pushed the bracket back with a screwdriver and tightened the screw. Working perfectly!!!! Only cost was replacing a few fuses before your fix! Much appreciate your time and effort to produce this excellent video.
My micro wave too small/ inexpensive for service call had power surges just last year taking out computer panel controls in all three major appliances since around that time it has been occasionally tripping breaker as starts the illumination for near by air vent above oven goes out as well but this last time started and wouldn't run checked breaker not tripped cost of pool arts may be too high to take the time my wife won't let me open it to check for fuses just hauled it outside since the recurring issue been increasing since power surges
An excellent explanation of the problem. One thing, though: The third bottom switch, the one that is just monitored by the logic board, should also cause the magnetron power to turn off, through the logic board noticing the open door and cancelling the cook cycle. The relative timing of this and the lower switch you are discussing should not be affected by door twist or the mispositioning of the bracket. On the other hand, there will be some delay due to the software on the logic board before the third switch opening and the magnetron power being shut off. So it is not entirely clear what interrupts the magnetron power when you open the door: the upper switch or the relay on the logic board.
@@EhButU I managed to repair one of these and the problem is that wear on the lower latch messes up the timing of the switch operation. With a new latch the two lower switches activate in the proper order (regardless of door twist) and everything works fine with no blown fuses/breakers.
@@kevinmartin7760 Using this video as as a basis to understand the switch order, I rebuilt the worn down bottom latch track - just layered some Polyurethane adhesive to rebuild the track. Did top and bottom latch filling in worn tracks and no longer blowing fuses - happy days.
Have the exact same microwave. Fuse would blow upon opening door. Tested all the switches and they were fine. Punted and purchased a new one (exact model as old one) yesterday. What a pain getting it on the brackets but finally got it. Figured it was 7 or 8 years old and not worth fixing. You have a good fix but can't control everybody in a house to open the door from the top every time. Not practical. Appliances don't last anymore. On my 3rd oven/stove (3 weeks ago) and now 3rd microwave in 27 years. First ones lasted 15 years.
Thanks. My microwave trips the breaker sometimes, usually after a period of not being used. If I haven't used it for some time, then I open the door, it trips the breaker. I tried flexing the door and making the locks latch out of order but nothing happened. Not sure if there is not enough flex or the design is different (not a GE micro).
You might have a limit switch that is sticking and not opening quickly enough. It’s not common but possible for this to happen if they have not been used for a while. If the “normally closed” switch does not open fast enough, that will trip the breaker. You might consider replacing both of them.
Our Microwave is not blowing fuses, it just does nothing, as if it were unplugged. When it first went out we assumed the Microwave was trashed, but the next morning it was back on and worked fine . It went off again that same but came back on later in the day and has worked fine for about the last month, but when it shut down the last time that was it. The fuse and the door switches appear to be working properly and I have power at the outlet. Any ideas would sure be appreciated. Thanks, Ray
Please reply, this is my problem but if the microwave was always opened from the bottom of the handle, do i need to push and support the bottom instead of the top??
Damn, the switches on my Breville aren't nearly as easy to access. Also, my fuze keeps blowing when i plug it in.... Is it possible this switch issue would blow the fuze?
so wait is the BOTTOM one suppose to lose contact BEFORE the top one? So in other words its tripping because the TOP one loses connection before the bottom?
Could you just remove the monitor switch? The monitor switch is normally closed meaning that it has an open circuit when the door is closed. Removing the switch all together would simulate having an open circuit 100% of the time (magnetron would never be able to rapidly dump power at the opening of the door). I would think that as long as the door interlock switch to cut power is working properly, there should be no safety issues removing the monitor switch.
This is a real pain in the ass, and GE* should have recalled all these units and fixed this serious flaw in design. * Yes, I know that GE has nothing to do with consumer products other than selling its name, and you can substitute Haer or whatever the actual maker is for GE.
I have a LG microwave that does not have power. I love my microwave and believe it may be a fuse. I don’t know how to get to the fuse. The model # is LMVM2277ST. Any help is much appreciated. Thanks
Start from the AC Power Cord Plug. Hot = Small Lead (Black), Neutral = Large Lead (White), Round Lead = Green wire Follow those wires into the microwave (you have to disconnect the AC Plug from wall & remove cover). Once you have located those three wires or use an ATG meter, the 20 Amp Fuse (white with metal on end) is parked Reply with email if you need more help to save you $600.00
you can also remove the secondary switch entirely from the equation, and leave it constanly open. found this little tid bit out when i had to fix mine. also the relay switch for the control bored can be removed and wired fully on.
sorry i also forgot that i had taped the primary switch to be fully closed at all times too. basically fooling the mic to think the switchs are actually all working properly yet none are really doing anything.
It's called pre-planned obsolescence, and it's strictly by design. We're in a no deposit, no return world now ... with our landfills expanding ever wider.
The bottom switch position has a lever that the 'door hook' rides on for a few mm and keeps that switch 'activated' a bit longer as you open the door. I moved my monitor switch (the middle one) (and it's wires) to the lower position so that it is guaranteed to deactivate last as it must to avoid the problem. I move the bottom switch with its wiring to the middle position where the monitor switch had been. (by activated, I mean in the position it is in when the door is closed, by deactivatated I mean the position the switch is in when the door is open) I'm wondering if the original designers didn't intend it that way. Now the unit shuts the magnetron off when the door is barely opened, and without shorting the AC line and dropping the breaker (and fusing the monitor switch contacts). Really poor design, and apparently used on many microwave brands.
