Locate and replace fuse - Panasonic NN-T993SF Microwave Oven

The fuse for the Whirlpool microwave model WMH31017HZ07 is located inside the microwave oven. You will need to remove the outer cover of the microwave to access the fuse. Here are the steps to follow:

1. Unplug the microwave from the power source.
2. Remove the screws on the top of the microwave that hold the top grill in place. Remove the grill.
3. Locate the screws that hold the control panel in place. Remove the screws and carefully pull the control panel forward.
4. Locate the fuse holder on the right side of the control panel. Remove the fuse holder by pulling it out.
5. Check the fuse to see if it is blown. If it is, replace it with a new fuse of the same type and rating.
6. Reinstall the fuse holder, control panel, and top grill.
7. Plug the microwave back in and test to see if the light is working.

If the light still does not turn on after replacing the fuse, there may be another issue with the microwave and it may require further troubleshooting or repair.

Although you have not mentioned the model/make, take a look at the video here for replacing a Thermal fuse. Microwave Won Work GE Microwave Thermal Fuse Replacement part WB27X1127

on traditional fuse see
How to Fix Microwave Oven Simple Fuse Replacement

Depending on the total part number 665xxxxxx a replaceable fuse is located behind the control panel usuallyon the floor of the control cabinet.

on one specific model "not yours" to check out the fuse locations a part number 309796 was found and I've included an image. Values of the fuses change based on specific models.


A typical location is included in the following image.


During previous repairs the fuse holder has failed and has required repair in addition to the fuse being replaced. This work needs to be accomplished by a qualified repair person. Even with power remove voltages remain because of stored engergy in the capacitors.

Hope this has been of help?

Mainly there are three/four fuses in Microwaves depend to maker.
First one to be checked it is on plug about 13A in cable out side microwave
Second one for power supply usually comes 10A located in terminal board of cable supply in side microwave if you follow the cable.
Third fuse i think about 5A for high voltage it located usually on wire connected between transformer and capacitor.
Fourth some Microwave have third one on the control board located behind switch panel.

now.

if the second fuse is blowing immediately after starting microwave that usually mean one or more of the following need to be replaced

1- diode
2- HV. capacitor
3- magnatiron

Which only can replaced by skill technicians

THANK YOU.

Well you need to find where the fuse is located, And determine what type of fuse is being used. So you know what fuse you need to buy to replace it.

How do you know you need to replace the fuse?

The fuse is generally located very near where the main power wires. It is most likely located inside so the lid must be safely removed and the unit must be unplugged. The power wire will run directly to the fuse in a block. Replace with the same size and type.

The fuse located under the keypad near the high voltage capacitor "silver and rectangular" unplug and discharge high voltage capacitor, fuse is a ceramic type, replace with same type and rating.

Unplug microwave, remove the top cover "several screws" fuse location under keypad and near the high voltage capacitor "silver and rectangle in shape" fuse is a ceramic type, must be replaced with identical fuse and rating, and don't forget to discharge capacitor with "long handle screwdriver"

Yes, is probably the fuse. I have fixed several microwaves with this problem and the fuse is almost always located just inside where the power cord enters the unit. Just remove the skin (usually screws on the back and BOTTOM also) test the fuse with a micro meter. If no contenuity, replace with same size, type and rated fuse. Most microwaves are 20amp fuse.

most likely the internal fuse
be soooooooooo carefull in replacing this , the capacitor inside the machine can store a huge charge

1. Turn off all electricity to the microwave and unplug from the wall socket. Move the unit to a well-lit location to better see the appliance.
   
2. Step 2 Usea schematic for the particular model of microwave being worked on tolocate the area containing the fuse to be replaced. Fuses can belocated behind the microwave door or behind a panel either on theinterior wall or an exterior panel. Often the fuse will be behind apanel located under the louver vents on top of the microwave.
   
3. Step 3 Removethe panel according to the manufacturer's instructions. Use a screwdriver to remove screws and set aside for replacement.
   
4. Step 4 Locatethe blown fuse and check with a voltmeter. This step ensures that theproblem with the microwave is indeed a blown fuse and not anotherissue. Check for current between fuse connectors.
   
5. Step 5 Take the blown fuse to a local hardware or store such as Lowe's or Home Depot. Staff can assist in finding the exact replacement fuse for the model being repaired.
   
6. Step 6 Placethe new fuse into the panel in exactly the same fashion as the blownfuse came out. Replace any panel using the removed screws and returnthe unit back to its proper location.
   
7. Step 7 Plugthe microwave into the wall socket and turn on all electricity. Testthe unit by ensuring the clock and all other features function.