A microwave is an essential kitchen appliance that has changed your life. Once you get used to a microwave, you will unwillingly develop some dependence. Typically, with frequent use, the machine might malfunction. But having a microwave that starts by itself is one of the strangest and most disturbing issues.
If your microwave turns on itself, it is delightful and useful. However, ignoring this issue will lead to unwanted escalations. First of all, it will increase your power consumption. This situation also negatively affects the lifespan of the microwave. So, you must address this issue as soon as it occurs to avoid undesired losses.
If your microwave shows symptoms of this problem, we’ll have your back. We will illuminate the possible causes and remedies for a microwave that turns on itself. So read on!
Why Does Your Microwave Turn On by Itself?
In most cases, your microwave will turn on itself when its door malfunctions. Also, there might be a problem with the appliance’s control board. Sometimes, there may be an issue with stuck switches.
Regardless of the cause, you can temporarily handle the problem until you properly address it. You can unplug your microwave right after each use. This way, there will be no power reaching the microwave. So, it won’t switch on by itself in the first place.
Before calling a professional, try troubleshooting the microwave independently.
1. Faulty Switches
Bad or malfunctioning switches are the main culprits in various microwave issues. However, it is often disregarded and never comes to the top. This issue is easy to handle as long as you correctly diagnose it. If your microwave starts by itself, you should inspect the door switch.
This switch relies on the on-and-off mechanism that facilitates the appliance’s operation. Also, this switch plays a critical role in the safety of the microwave oven. Despite its small size, this switch prevents the oven from starting whenever its door is left open.
Whenever this switch malfunctions, there will be no power reaching the door. Sometimes, a malfunctioning door switch will result in an ongoing supply. This will lead to the unexpected operation of the microwave fan despite closing the door.
2. The Device Needs Resetting
Sometimes software glitches or incorrect settings make some microwave models malfunction. So, a microwave that turns on by itself might use some resetting. There are different ways that you can troubleshoot this issue. However, a soft reboot or reset is often a suitable solution.
3. There are more Difficult Glitches
Sometimes, multiple or more difficult glitches won’t get fixed quickly. In this case, you will have to go the extra mile. This means you will have to perform a hard reset. This process is helpful whenever you have activated or chosen the wrong setting. In some cases, a hard reset can fix the issue of a microwave starting on its own.
4. A Faulty Membrane Keypad
A membrane switch is a vital component of a microwave’s touch panel. It consists of sensitive electrical switches that operate via the soft touch technique. This type of switch is not made of only plastic but consists of two different layers: one is plastic on the bottom, and the other is made of conductive rubber and is on the surface.
With frequent use and ongoing contact, the rubber layer will wear out. This will break the circuit and eventually lead to malfunctions. So, the microwave will either stop operating or turn on itself as long as it is plugged into the power outlet.
To ensure the membrane switch is the culprit, you should test it with a multimeter. If the switch is dead, the tester will receive no resistance.
5. A Defective Control Panel
After excluding all these culprits, it is time to consider the oven’s control panel. This panel is the brain of the appliance. This vital component is found right under the keypad. The panel is responsible for inputting and outputting information on the cooked food.
It also contains multiple buttons controlling the oven’s functions. The oven might start on its own whenever something is wrong with the panel.
6. A Malfunctioning Heat Sensor
There are some models of microwaves designed to be placed over the stove. These models are known as over-the-range microwaves. These models are susceptible to heat. These models are very responsive to the slightest press or touch from the user’s finger.
Such sensitivity makes the microwave respond to the slightest heat from any other source in the kitchen, including cooking steam. This ends up making the microwave operate without the need for it. This sensitivity usually indicates that the heat resistance sensor is no longer working.
How to Fix a Microwave That Turns On By Itself
You will need a functional microwave to be able to use your kitchen. You will need to address this problem without delay. Aside from the substantial power waste, this faulty microwave might become a serious fire hazard. So, addressing the issue spares you many damages and losses you are not ready for.
1. Replace the Faulty Interlock Switch
A faulty switch in the door will cause an open circuit. This means there would be zero power flowing throughout the circuit. But sometimes, this scenario might lead to unwanted microwave oven operation as the lights will turn on and the fan will function too.
Before buying a replacement, check the appliance’s warranty. If the warranty covers the door and its components, it is better to call the manufacturer. Otherwise, you can quickly fix this issue if you are a DIY enthusiast.
Remove the appliance from any power source and remove its grill. Remember to work on the replacement process after removing the control board and the door switch assembly. You can easily install the new switch once you are done with all these steps without cutting or damaging any wires.
2. Try a Soft Reset
Sometimes, the problem lies in simple glitches in the device’s system. This issue might stand behind various issues with microwave malfunctioning. The same thing applies to other electronic devices that use software to operate. This is not necessarily the cause of your problem, but this method is worth trying.
Generally, a soft reset is easier to perform, especially when compared with a hard reset. You can find a reset/cancel button on one of the sides of the display board. Despite being in a wide range of microwaves, some lack this button.
You can still perform this reboot if you have one of these ovens. It only takes holding the off button for around 7 seconds. This should do the deed.
3. Try the Hard Reset
The hard reset option works just fine whenever the soft option fails. It can free a microwave that is stuck. It takes longer than the usual soft reset but is more effective. Experienced appliance technicians recommend performing this procedure when the device is not responding or starts by itself.
This is performed by unplugging the microwave and leaving it without any power source. This should stay in this situation for nearly an hour. This allows the electrical circuit to disappear until it dissipates gradually. This type of reset can fix complicated software errors.
4. Replace the Membrane Switch
Fortunately, replacing the membrane switch does not require professional intervention from a certified appliance repair business. You can easily DIY this task. Keep in mind that these switches are not sold separately. You must purchase a whole new membrane frame to replace a malfunctioning membrane switch.
5. Get a New Panel
A microwave’s control panel contains the control board and the touch keypad. As a result, the oven will malfunction and start running on its own if something goes wrong with one of them.
You can identify a malfunctioning panel by its self-contained appearance. Also, the panel will give orders to the oven on its own. In this case, you will have to get a replacement.
6. Replace the Heat Sensor
The heat resistance sensor on an over-the-range microwave is part of its touchpad. If this sensor is no longer functional, the oven will turn on at the slightest sign of heat in the kitchen. You can replace this part without replacing the whole panel.
Adrian is an ISCET licensed professional that has completed the National Appliance Service Technician Certification Exam and has the expertise to diagnose and repair any appliance. He is well-versed in the latest technologies and techniques and is always up-to-date on the latest industry standards.
