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Read a response you made a few years back about replacing a fuse on a KAid KHMS155LSS4 microwave. While replacing the microboard on mine, I failed to connect the ground during assembly and it sparked against the outer box, tripping the breaker at the panel. All is assembled correctly, there is power at the plug, and the microwave is dead in the water. The Thermal Fuse (I believe it is called) sits just behind the control panel, but I can not get to it. Voltage meter reads on the connection at the top of the fuse, but not on the bottom? I am working on the assumption that I blew a fuse (or two). Will I have to remove the entire unit and break it down further just to try this fuse?

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It sounds like you have already diagnosed the problem, by testing voltage. You will most likely have to remove the cover to access the fuse. They are somewhat hard to reach. Make sure you replace with the exact same rating fuse.

Posted on Nov 07, 2010


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Error code F2

Per the tech sheets (page 8), "F2" error code means "Keyboard failure". Recommended by the manufacturer to replace the touch panel first and, if it would not solve the problem, then the control board has to be replaced too. Not the best recommendation but we have to follow it.

- The part number for the touch panel (aka a membrane switch) is AP3130765

- The part number for the control board AP3130764

Here are the break down diagrams for the Kitchen Aid microwave Model KHMS155LSS4

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May 28, 2015 | Microwave Ovens

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No power to the microwave, after storm.

The low voltage brownout let the oven draw too much current, and likely an internal fuse failed. Typically after removing a dozen Philips screws you can take off the cover and locate the fuse, which you can match and replace. [If it still has "power" (like the lights come on) but has stopped heating, then it could be any number of other issues (main capacitor fail, etc)] I've changed a fuse or two in my day, and years ago a failed capacitor, with success.

Jan 13, 2014 | GE Microwave Ovens

1 Answer

Whirlpool microwave/wall oven model # GMC275PDQ3 not working

see this steps and use the common sense NOT feared: unppluged the power cord:
Lights come on, but can not program unit, Touchpad dead If you have a stuck key or non-responsive key, most of the time you will have to replace the keypad for this microwave oven repair. If your keypad is connected to your control board by a flat ribbon wire, try disconnecting it and clean the silver contacts with an ordinary pencil eraser. After cleaning, plug it back in and try it. If it doesn't fix it, replace the keypad unit. Some units actually have keypad tests to confirm your diagnosis of a bad key.
If your keypad and control is the same unit, replace that unit. Another note, unlike stove/oven keypads and controls, most microwaves do not have error codes or tests to distinguish whether it is truely the keypad or control. Most of the time, it is the keypad that needs replacing, but a small percentage of the time it can be the control. Check the tech sheet if they can point you to the right part.
God bless you


Jul 27, 2012 | Microwave Ovens

1 Answer

Kitchenaid khms155lss4 microwave combo went dead what fuse should i check frist

Check to make sure you are getting power to the receptical, plug a lamp to confirm. Next unplug microwave oven and remove top, "several screws" now look inside where the keypad is, follow the wiring to the circuit board, there should be a small glass or ceramic fuse clipped in, before you take it out discharge silver rectangular capacitor with a screwdriver across the points to make sure all voltage is removed. Now unclip the fuse and test, if open replace with the same current rating, if no change I recommend a technician to take it further. Please remember there is extreme high voltage when unit is plugged in and running making it lethal, put the top back on for safety sake.

Mar 02, 2012 | KitchenAid KCMS145J Microwave Oven

3 Answers

My microwave is 4 years old. It stopped heating about 2 years ago. The light works, the microwave timer works, the microwave itself will turn on, but it won't heat anything. Could this be a simple part...

Hi and welcome to FixYa, I am Kelly
Often it is a simple part replacement. There are 3 parts that can cause this. The most common failure is the power diode. You remove the chassis to gain access and then make sure you hold a screwdriver and ground the large capacitor at least 3 times across the terminals. Then you can check the diode by using an ohm meter across the terminals. It should read continuity in one direction only. (reverse lead polarity) If it reads in both directions OR there is no continuity then the diode has failed. Next you test the high voltage capacitor by reversing the leads and watching each time for a jump in resistance then the meter returns to infinity. (Diode must be disconnected) No jump in resistance after reversing the test leads or constant resistance = bad capacitor. Lastly the Magnetron could have failed. You read resistance of the leads of the Magnetron with one lead disconnected. You must read resistance. No resistance = bad magnetron.

Since you did not include a model number this response assumes you have a non-inverter powered unit. If you need more specific information or have an inverter powered microwave I need a complete model number in your response so I can pass on parts sources and unit specific checks.

Thanks for choosing FixYa,

Jan 22, 2011 | Whirlpool Microwave Ovens

1 Answer

Blew the fuse. I replaced it and it blew again after a few minutes.

Sorry to read about your problem, I hope this helps you out.

you have a control card problem, or a bad power control card issue..
I tried to help you. Please help me and Rate/Vote on my response, thanks and good luck

Dec 25, 2010 | GE JE2160 Microwave Oven

1 Answer

I have a Kenmore countertop microwave that is almost ten years old. I was using it one day, heard a pop and it quit. Could it be a fuse and how do I get the back off?

Usually when you hear a pop during operation and it quits either the Power Diode or High Voltage Capacitor has failed. When they fail they usally also cause the internal 15 Amp fues to fail. The back comes off by removing the 4 screws (2 on each side) and 6 screws in the back. (UNPLUGGED!) The you slide the cabinet cover back about 1/2 inch.. lift the rear of the cover 30 deg and remove the cover by pulling to the rear of the unit.

Once inside take a bladed screwdriver and short across the capacitor at least 3 times just incase it was not the failure. If you don't do this and the Cap is good it can really ruin your day! Then isolate the Cap by removing the set of terminal connections tht includes the power diode connection. Use an analog meter on R x 10K and probe the cap terminals. You should see resistance then watch the resistance increase to infinity. Reverse the leads and watch for the same indication....resistance then increase to infinity. It should do this each time you reverse the leads. To check the diode you read both ways with the meter leads across the diode. One way will read ZERO ohms and the other way should read close to infinity. (You have to reverse the leads.) Like I said usually the Cap or the diode fails. Make sure you check the fuse for continuity also. Most of the time they fail when one of the 2 components above fail. DO NOT replace the fuse until you replace the failed part. Otherwise the fuse will fail again.
The fuse is located in the fuse block at the end of the power cord.
When your reinstall the cover make sure you ensure the front side locking tabs near the bottom front are engaged with the front of the internal chassis.

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Sep 04, 2010 | Kenmore Microwave Ovens

1 Answer

Is there a reset button on the goldstar ma-782m I was boiling an egg and now it won't come on

No there is not a reset button. Most of the time when the microwave is in use and just quits either the Power Diode or the capacitor has failed and blows the fuse inside the cabinet.

With the unit unplugged and the chassis cover removed the fuse will be located at the end of the power cord lead in a fuse holder. The fuse is usually a 15A 250V slow-blo fuse. Just replacing the fuse will normally result in the fuse failing yet again.

STOP! Before going any further you must hold a well insulated screwdriver back on the handle and short across the High Voltage Capacitor at least 3 times! Failure to do so could be the start of a very bad day in the form of a horrible shock.

Next you disconnect one side of the cap including the power diode wire. With an analog meter set on R x 1,000 read the Cap terminals watching for a jump. Reverse the meter leads on the terminals and watch for a jump EACH time you reverse the test leads on the CAP terminals.

No jump = bad cap.
Constant resistance across the cap = bad cap

Lastly you check the power diode with the meter on the same settings R X 1,000. One direction will read full continuity (ZERO) and reversing the leads will read infinity. (no reading)

If the diode reads open both ways = failed
If the diode reads (ZERO) both ways = failed
It must read continuity in ONE direction only.

After finding and replacing the failed component then you can change the fuse and test the microwave.

There is a very very remote possibility that a door switch has failed but given that your microwave failed while in use I seriously doubt you have a door switch problem.

As far as finding replacement parts for your microwave nearly every appliance parts store will have what you need if you walk in with the failed part in hand. Most of the time they will walk back and grab the part you need without even digging in the parts books.

Thanks for choosing FixYa.



Aug 31, 2010 | Goldstar MA-782M Microwave Oven

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Magic Chef Model #MCO160UW

Call 888-775-0202 Magic chef they will replace the part free of charge even if its not longer under warranty

Aug 14, 2009 | Magic Chef CMV1000B Microwave Oven

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R-4H84 Sharp Carousel II microwave oven stoped working

A microwave can be dead for many reasons.

The fuse is normally located on the floor of the chassis behind the control panel or between the door switches.

If the fuse is good, it may be an open thermostat or thermal cutout (TCO) / thermal fuse on or near the magnetron or on top of the cavity / body of the oven.

If it goes dead for a while during or after cooking then comes back on, the magnetron is probably overheating and causing the magnetron thermostat to open.

Then when it cools, it closes the circuit and allows power through again.

When checking thermostats, if it has a hood fan thermostat, that should read open, as opposed to the others, which should read closed.

If it went dead almost immediately after pressing the Start pad, that's usually a shorted high-voltage capacitor.

If it went dead a few seconds after pressing the Start pad, that's usually a failing high-voltage transformer.

If it goes dead or blows the breaker when you plug it in or open or close the door, then there's a problem with a door switch or door switch mount.

If it's intermittent or random, it may be a bad connection, usually on the control board or a loose fuse holder, or even an intermittent fuse.

You should do a continuity test on the fuse while it's in the holder (with the microwave unplugged, of course) then turn the fuse by hand or take it out and put it back in, then test it again.

If you remove the fuse, then press the meter leads against the ends, it can allow internal contact to be made and make a bad fuse appear to be good.

If you or someone you know decide to look into it, we have critical safety information and disassembly information at our site, and our link is at our listing here on FixYa:

We're happy to help and we appreciate your thoughtful rating of our answer.

Jun 19, 2008 | Sharp R-1490 Microwave Oven

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