Nothing is worse than a broken microwave when dinner time rolls around. Luckily, microwave repair is not rocket science. A handy person with a bit know-how can fix most microwave repair related problems. Check out our list to learn the basics.
Microwave Repair Made Easy
Kitchens without a microwave unit quickly become inconvenient places, especially for people that rely on them often for cooking. Annoyances associated with a broken microwave range from undercooked food to dangerous electrical threats.
As such, it is essential to address any microwave problems early on, or else they may get much worse. Luckily, microwave typically only need a replacement part or cleaning maintenance to get up and running again.
Many of the issues broken microwaves exhibit are very common. Because of this commonality, it is relatively easy to attempt a do-it-yourself home repair. But first you need to know what is actually wrong with your microwave. We have listed the seven most common reason problems that broken microwaves exhibit.
Locate yours and see if you can fix it yourself. If not, you will likely need to take it into a professional. But it is always smart to try it yourself first. You might save a trip to the hardware store and some money.
The Microwave Touchpad is Not Responding
Unresponsive touchpads are by far the most common microwave problem people have. Most of the time, the issue with touchpad lies in its membrane switch. The membrane switch is a series of soft-touch electric switches. The switches are coated with a conductive, plastic material which, when pressed, bridge the gap and initiates an electric current.
After frequent use, this plastic material lining the buttons begins to wear away. When the plastic lining wears away, it is much harder to establish an electrical connection.
To test the membrane, switch the first thing you will have to do is unplug the microwave a move it to a location where you can work on it. It is helpful to have the electrical schematic of your specific model before proceeding. Look for the control panel and a flat ribbon connector. Follow the connector, and you will find the membrane switch.
Test the connection with a multimeter — several ohms of resistance should be present. If there is no connection, you will need to replace the touchpad.
If the touch membrane is not the issue, then it is likely the smartboard itself. The smartboard controls the impulses sent from the membrane switch. We will go over how to fix this in problem 3).
The Microwave Makes a Strange Noise When Operating
Try to find out where the unusual noise is coming from to see where the microwave needs repairing. If the sound is coming from the turning apparatus, there may be something wrong with the with the drive motor. The drive motor is the device which turns the glass tray in a microwave. If the engine is making a grinding sound, it will need replacing. Unplug the microwave, and undo the screws and wires securing the motor to inspect it.
If the microwave is making a loud, humming noise, the problem may be one of two things: the high voltage diode or the magnetron. Before checking either of these parts for microwave repairs, make sure everything is unplugged.
Electric shock can occur since both of these pieces are part of the primary circuit.
- High voltage diode — Along with the magnetron and capacitor, the high voltage diode allows the microwave to produce heat. Check the high voltage diode with a multimeter to see if there is continuity. If the multitool shows no continuity in one direction or the other, it will need replacing.
- Magnetron — The magnetron is another part of the circuit that works to produce heat in the microwave. Often it is merely a matter of tightening the mounting bolts on the magnetron, which can become loose with frequent use. Give this a try and see if it fixes the humming. If it continues to hum, it is damaged and will need to find a replacement.
The Microwave Will Not Turn Off
When a microwave keeps running even after the door opens, there is likely something wrong with the door interlocking switch. A properly functioning door interlocking switch will interrupt the power of a microwave as soon as the door opens.
You can access the switch by a latch on the microwave door. Check to make sure the two wires are attached to the common and NO (normally open) terminals. If the connection breaks, the piece will need a replacement.
If the stop button on a microwave does not work, but the microwave stops when you open the door, then the issue probably lies with the smartboard. Try testing the relays of the smartboard for continuity. If continuity occurs, the smartboard will need replacing.
The Microwave Does Not Produce Any Heat
If your microwave turns on but does not produce any heat, then there is something there is something wrong with high voltage circuit — either the individual pieces or the door interlocking switch. Follow the advice previously mentioned in microwave problems 2) and 3). Check the high voltage diode, the magnetron and the door interlocking switch for potential issues, and order any replacement parts that are necessary.
The Microwave Door Is Broken
If the microwave door cannot open, or stays closed, it is likely due to to the door latch assembly. To fix this, find the latches’ two levers which connect to the switch holder found by the frame of the microwave. If the bars are appropriately combined, they will make the switches power the microwave. A loose spring or a wobbly lever is all it takes for a microwave door latch assembly to malfunction. Try adjusting the pieces. If this does not work, you will need a door latch assembly replacement.
The Microwave Tray Will Not Move
Most of the time when the tray will not move it is likely because the roller guide is not adequately in line with the coupler. This misalignment results in the microwave glass tray falling off the manual, or just not moving at all. Adjust the roller guide and tighten any loose parts on the coupler. If the roller guide or coupler are damaged, they will need a replacement part.
A more pressing issue is the drive motor. This part is the motor found under the coupler that physically initiates the spinning. To remove the engine for a continuity test, move the couple and roller guide. Keep a screwdriver handy to remove any screws or bolts. If the multi-tool shows no continuity, you will need to order a replacement part. If the tool show continuity, but the drive motor still is not working you will need the help of a qualified professional.
The Microwave Exhaust Fan Will Not Start Up
One of the most common causes of broken exhaust fans is a dirty grease filter. You can locate the grease filter at the bottom of the microwave. Its job is to keep debris from food particles from clogging the exhaust system on a microwave. An easy fix is to remove the grease filter, which is usually supported by screws or bolts, and then give it a thorough cleaning. Make sure to remove all the oil and grease that has built up around the opening, or the fan will not operate correctly.
If the exhaust fan still does not turn on, then the problem may lie with the damper assembly. The damper assembly keeps external air out of the microwave during the heating process. To access the damper assembly, you will need to remove the microwave from the wall or panel to which it is attached. If you cannot find any spare pieces or foreign objects blocking the damper assembly, then it is broken and will need replacing.
Of course, there might be something wrong with the exhaust fan itself. If the fan is not able to move with the spin of a finger, it is damaged and will need to replace it. However, if the fan does run it may merely be the connection, Test for continuity with a multitool and see if you can rewire the fan without replacing it.
Microwaves are complicated machines, so do not feel bad if you have to take it to a professional to repair it. However, you can save a significant amount of money by troubleshooting the problem yourself. You may have to buy a replacement piece, but this is far cheaper than a new microwave or repair. While it might be more effort, you will also gain more in-depth technical knowledge of the machine you use every day.
We hope our guide helped you identify your microwave’s specific problem, as well as advice on how to repair it. Always consult your microwave’s specific brand schematics before tinkering, since part placement sometimes differs from model to model. You can find these resources online.