Microwave Starts when the Door is Closed

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Updated Jun 27, 2022 11:13 PM

Even if you have a top-tier microwave oven, you may run into issues like a microwave that starts when the door is closed. Luckily, your house isn’t haunted — it’s your microwave’s electronic components. While a microwave starting on its own isn’t immediately dangerous, you should contact a microwave service if you cannot handle the repairs. So, if your microwave automatically turns on when you close the door, read our guide to see the real issue.

KEY TAKEAWAYS:

  • If your microwave runs with the door closed, you should unplug it from power.
  • The most common cause is lousy control units on the microwave board.
  • A faulty interlock switch will also cause this issue along with a whole host of other electrical problems.

Why Is My Microwave Starting on Its Own?

A constantly running microwave oven is a somewhat common issue. As a result, your control panel will be unresponsive most of the time, and your microwave display might be blank. Unfortunately, repairing this problem is a dangerous endeavor on almost all microwave models.

Insider Tip

Unplug your microwave if it won’t stop running. Leaving it powered on will waste energy and might lead to electrical damage to your home.

So, if you see these symptoms, you need to reach out to a professional for microwave repair. That said, you should understand the causes before shopping for solutions. If you have an older microwave, you may also need to repair microwave rust before cooking again.

Bad Control Board

The most common cause of a constantly running microwave oven is a control board issue. The control panel relays messages from the touchpad to the internal fuse. You’ll notice this issue if you also have a defective touch-pad or control panel that won’t respond. But, again, this is a safety issue, and you should not touch your membrane keypad without rubberized gloves.

Bad Interlock Switch

A faulty switch is a more common issue than a bad control board. This is because the electronic components under the control panel check the switches for continuity. A bad door switch with bad continuity switches can blow your circuit breaker and cause a whole host of other electrical issues. Read our guide for how to fix a microwave door switch if you think this is the problem.

Warning

Microwave repairs can be dangerous. Make sure you have proper training as an appliance technician if you want to perform appliance wiring services.

F.A.Q.S

Why won’t the light in the microwave turn on?

If your microwave light bulb doesn’t turn on, you likely need to change it out. That said, if the light still doesn’t work after replacing it, you have a bad keypad or button release mechanism.


Why is my microwave sparking?

Most of the time, sparks in your microwave are from stainless steel or metal trim piece utensils or dishes in the microwave. That said, the issue may be dirt or a lousy high-voltage capacitor.


How do I reset my microwave?

Even if you have a range microwave, you can reset the appliance by hitting the clear/cancel button. If your microwave still doesn’t respond, unplug it to do a hard reset.


Is it dangerous if the microwave runs with the door open?

While you will not suffer fatal damage, you will experience increased amounts of microwave radiation. As a result, you may experience a tingling or warm sensation on your hands and face called diathermy.


STAT: According to a US Department of Energy survey, male respondents reported using their microwave 50 percent more than women. (source)

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