There is no point having a microwave if it doesn’t work. However, before going to replace your microwave, try following these steps. We are going to show you what to do if your microwave is not working.
Table of Contents
Causes of Microwave Not Working
If the problem you are experiencing is that your microwave turns on but doesn’t heat, it could be from the diode, line fuse, thermal fuse, or magnetron. However, if the microwave doesn’t turn on at all, this problem could be from a different component or components. So here’s how to replace the possibly faulty components…
The Diode
To replace the diode in a microwave follow these steps…
Step 1: Unplug the microwave.
Step 2: Remove the screws at the top of the front vent of the microwave.
Step 3: Open the microwave door and remove the vent.
Step 4: Remove the screw beside the control panel.
Step 5: Lift the control panel up then slowly lift it out.
Step 6: Remove the screw which holds the inner access panel in place.
Step 7: Take the panel out.
Step 8: Discharge the capacitor before going any further. You can do this by placing a screwdriver with an insulated handle over the two terminals of the capacitor.
Step 9: Take out the screw which holds the diode to the frame.
Step 10: Disconnect the old diode from the capacitor. Test the diode using a multimeter to determine if it is good or not.
Step 11: If the diode is faulty, get a new one and install it by connecting it to the capacitor first, then screwing it to the frame.
Step 12: Return the inner access panel and secure with the screw.
Step 13: Push the control panel back in and use the screw to hold it in place.
Step 14: Return the front vent and the screws at the top.
If your microwave is not working still, read on to see if you need to replace any other component.
The Line Fuse
If your microwave is not working but has power, also try replacing the line fuse. To check and replace the line fuse in a microwave, do the following…
Step 1: Turn off the microwave and unplug it.
Step 2: Take out all the screws at the back of the microwave
Step 3: Also take out the screws on the two sides of the microwave.
Step 4: Remove the microwave cover.
Step 5: Take out the line fuse from the holder.
Step 6: Test the fuse for continuity using a multimeter. If there is no continuity, you will need to replace it.
Step 7: Get a new line fuse and place it in the holder
Step 8: Return the microwave cover and secure it with the screws.
The video below walks you through how to replace a microwave line fuse if your microwave is not working.
The Thermal Fuse
To replace the thermal fuse in a microwave, do the following…
Step 1: Turn off the microwave and unplug it.
Step 2: Open the microwave door and take out all the screws which secure the front vent.
Step 3: Remove the front vent by sliding it to the left then pulling it out.
Step 4: Remove the screw right next to the control panel and loosen the other one behind it. Some microwave models will not have any screw behind the control panel.
Step 5: Lift the panel up then out.
Step 6: Disconnect the wires from the thermal fuse.
Step 7: Take out the screw securing the thermal fuse to the frame. Test the thermal fuse using a multimeter.
Step 8: If the thermal fuse is faulty, get a new one and screw it down to the frame.
Step 9: Connect the wires to the new thermal fuse.
Step 10: Push the control panel back in and return the screw beside it. Also tighten the other screw behind it if your microwave model has one.
Step 11: Return the front vent and secure it with the screws.
If your microwave is not working still, call a technician.
The video below will show you how to replace a microwave thermal fuse.
Check out these articles…
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Microwave Is Working But… [Problems Solved]
Buttons on Microwave Not Working
If some of the buttons on your microwave aren’t working, you need to replace the whole control panel. However, if all the buttons aren’t working, you will have to replace the control board. To replace the control panel in a microwave, do the following…
Step 1: Unplug the microwave from the socket.
Step 2: Take out the screws at the top of the front grille.
Step 3: Slide the grille to the left the take it out.
Step 4: Take out the screw that secures the control panel to the microwave.
Step 5: Note where each wire goes on the control board then disconnect them. To make your job easier, take a picture before disconnecting the wires.
Step 6: Take out all the screws which secure the control board to the panel.
Step 7: Disconnect the ribbon connector then take out the control panel.
Step 8: Use a screwdriver to remove the control board mounting plate from the panel.
Step 9: Get a new control panel and place the plate back on it.
To replace the control board, follow all the steps up to step 7 then screw the new board to the plate.
Step 10: Reconnect the ribbon connector.
Step 11: Return the control panel to the microwave.
Step 12: Connect all the wires back to the control board.
Step 13: Push the control panel back into place.
Step 14: Screw the panel back tightly.
Step 15: Slide the vent back in and secure it with the screws.
Watch the video below if you would like a visual of how to replace a microwave control panel.
Microwave Is Not Working After Using Metal
If you have read your microwave manual, you will know that using anything metal in a microwave is very dangerous. When you use metal in a microwave, the microwave begins to spark and eventually blows. If you have just used metal and your microwave is not working anymore, you may have to replace the microwave. Do not try to fix this problem yourself.
Microwave Not Working After Slamming Door
If a microwave door is slammed hard enough, it can cause the fuse to blow. So if your microwave is not working after slamming the door, try replacing the fuse. To do this, follow these steps…
Step 1: Turn off the microwave and unplug it.
Step 2: Take out all the screws at the back and two sides of the microwave to be able to remove the cover.
Step 3: Remove the microwave cover and set it aside.
Step 4: Gently pry the old fuse from the holder.
Step 5: Get a new fuse and place it in the holder.
Step 6: Return the microwave cover and hold it in place with the screws.
Step 7: Plug the microwave back in and test it out.
Microwave Not Working After Running Empty
Running a microwave empty can damage the magnetron. So, if your microwave is not working after running it empty, the magnetron is damaged.
A magnetron is a very complex and expensive component to replace. It costs almost as much as a microwave. Do not try replacing this part if you are not experienced or else you could end up damaging the microwave even further.
The video below will show you how to replace a microwave magnetron.
Fan in Microwave Not Working
If the fan in your microwave is not working, it could be because of the control panel, control board or the fan motor. Before you replace any of these parts, get a technician to determine which one is actually faulty. Then, if you need to replace the control board or panel, look at the “Buttons not working” section.
Display on Microwave is Not Working
If the display on your microwave is not working, the first thing to do is check the power supply. If the buttons don’t work and the display is completely blank, the microwave may not be plugged properly. If the plug isn’t tight, push it in.
A tripped breaker can also cause this problem. Go to the circuit breaker in your house and find out which one is for your microwave. Make sure it is totally on. If it isn’t first turn the switch off then switch it back on.
You may need to replace the control panel if none of these solutions work. To know how to replace the control panel in a microwave, check the “Buttons not working” section.
