As far as we can tell, no ghost is causing your Samsung microwave to turn on by itself. It’s most likely dirt build-up or moisture causing your microwave to turn on automatically.
In our guide, we’ll show you how to identify the source of your problem and direct you to the best solution.
Not to worry, your microwave probably just needs a deep cleanse, which should take 10 minutes or less. We’ll give you step-by-step instructions on all the fixes, so you can troubleshoot the issue with confidence.
Why is my Samsung microwave turning on by itself?
Your Samsung microwave is turning on by itself because of dirt buildup on the doors or moisture on the glass panes. Cleaning your microwave should resolve your problem immediately.
If you’re dealing with a faulty component, you can replace it yourself. Or, you can ask for professional help.
How to Fix a Samsung Microwave That Turns On by Itself
If your Samsung microwave turns on by itself, power cycle it first. Unplug it for at least 60 seconds, and check if it solves your problem.
Clean your microwave, including the door and latch mechanism, if it still turns on by itself. If the cooktop lamp won’t turn off, it probably just needs to dry.
We’ve listed the four most common issues that happen when your Samsung microwave turns on. We’ll also help you understand what causes these issues to happen and how you can resolve them.
| Issues | Causes | Solutions |
| The light turns on after closing the door. | There’s too much dirt and grime build-up in your microwave. | Unplug your microwave. Create a 1:1 mixture of vinegar and water. Dip a microfiber cloth in your mixture and use it to wipe your microwave clean. Clean all the grease and grime off of your microwave, including the door, latch, and latch mechanism. Take a clean microfiber cloth and wipe your microwave with it. Let your microwave fully dry before closing its door all the way. |
| The door switch is faulty. | Unplug your microwave and open the door. Unmount the screws on the microwave cover. Then, remove it and set it aside. Remove the control panel to access the door switches. Unmount the switch assembly and free the wires from the retaining clips. Test your door switches to find out which ones are malfunctioning. Press each switch and listen for a clicking sound. Push the release tab on the door switch with weak or no clicking sound. Replace it with a new door switch. Reinstall the control panel. Finally, reattach the top cover and its screws. | |
| The cooktop lamp won’t turn off. | The cooktop lamp might be wet from cooking food with high water content. | Leave your microwave door open for at least 15 minutes to let the moisture dissipate faster. Use a clean and dry microfiber cloth to wipe the moisture inside your microwave and on its doors. |
| The vent fan automatically turns on. | The vent fan automatically turns on to dissipate heat from the cooktop. | You can’t turn off the vent fan once it’s activated by the automatic function. It will turn off when it detects a safe temperature. However, you can help your microwave cool down faster by promoting better airflow. Make sure the air vents aren’t blocked and maintain adequate ventilation space on all sides of your microwave. |
| The microwave starts on its own without any interaction. | The main control board is faulty. The touchpad or control panel is malfunctioning. | Contact Samsung’s Support Center for assistance. You might need professional help to replace the malfunctioning components. |
The light turns on after closing the door.
If your microwave’s light is turning on after you close the door, you might have dirt build-up or a faulty door switch.
Cleaning grime off your microwave will be a lot easier than replacing a malfunctioning door switch. Nevertheless, you can replace a faulty component in under 30 minutes if you follow our instructions carefully.
Dirt Build-up
Dirt or food can get stuck in your door mechanism, especially if you don’t clean your microwave as often as you should. This build-up of gunk will prevent your door from closing properly.
After cleaning it thoroughly with a damp cloth, your door should close all the way and your light will turn off.
Solution: To clean dirt build-up in your Samsung microwave, follow these steps:
- Step 1: Unplug your microwave, or power it off at the circuit breaker.
- Step 2: Open the microwave door.
- Step 3: Pour a 1:1 mixture of vinegar and water into a bowl.
- Step 4: Dip a microfiber cloth into the cleaning mixture and wring it out.
- Step 5: Wipe all the grease and grime off of your microwave. Clean the interior, door, latch, and latch mechanism.
- Step 4: Wipe your microwave dry using a clean microfiber cloth.
- Step 5: Leave the door open for a few minutes to let your microwave dry.
- Step 6: Close the door all the way once your microwave is fully dry.
| Tips: If you don’t know how to clean a microwave, you can do more harm than good. Here are a couple of reminders to help you clean your microwave effectively and safely. • Always unplug your microwave before wiping its interior or exterior so it doesn’t turn on by itself. • Mix one part vinegar and one part water into a heat-safe bowl. Microwave your mixture and leave it inside for a few minutes to remove stubborn stains and grease marks. • You can add a few drops of essential oils into your cleaning mixture if the scent of vinegar is too strong for you. • Dip your microfiber cloth in the vinegar mixture, and use it to clean your microwave. • Ideally, you should clean your microwave weekly. However, if you see visible splatters and grime on your unit, you shouldn’t wait until the end of the week to clean it. • After cleaning your microwave, leave the doors open and let it dry for a few minutes. Closing the door immediately after cleaning will trap moisture inside and become a breeding ground for bacteria. |
Faulty Door Switch
Typically, your Samsung microwave has three door switches. When they are functioning properly, they prevent your microwave from turning on when the door is open.
If a door switch gets stuck, it relays power to other components like the lights or the vent fan, causing them to turn on.
Solution: To fix your Samsung microwave’s faulty door switch, follow these steps:
- Step 1: Unplug your microwave.
- Step 2: Remove the screws on the top cover of your microwave.
- Step 3: Open the microwave door.
- Step 4: Grab the top cover and slide it to the left. Carefully lift it up and pull it towards you to remove it.
- Step 5: Unmount the control panel to access the door switches.
- Step 6: Remove the two screws mounting the switch assembly.
- Step 7: Free the wires from the retaining clips.
- Step 8: Test each switch to see which one needs changing. Just press the switch and listen for a clicking sound.
If you hear weak or no sound at all, you should replace that switch. You can opt to replace all three of them just to be sure.
- Step 9: Push the release tab on the door switch that needs a replacement. Then, gently pull it out of the housing.
- Step 10: Disconnect the wire from the faulty door switch.
- Step 11: Take your new door switch and install the wires.
- Step 12: Reinstall the control panel and its screws.
- Step 13: Reattach the top cover and secure it in place.
- Step 14: Plug your microwave back in.
| Tips: Replacing a faulty door switch on a Samsung microwave seems so intimidating, but it’s easier than you think. Here are a few tips to help you with this fix. • Get the correct door switch replacement for your Samsung microwave model. • Check your user manual to find out the right voltage and switch type for your unit, or check your old switches. • Each door switch has two connectors. Before disconnecting them, take pictures so you know which wires go on which switch when it’s time to reassemble them. |
The cooktop lamp won’t turn off.
If your cooktop lamp won’t turn off, it’s most likely caused by excess moisture inside your microwave.
Moisture in your microwave is normal, especially after cooking food with high water content. The excess moisture usually dissipates after 10 to 15 minutes.
Solution: To fix a cooktop lamp that won’t turn off, leave your microwave door open for at least 15 minutes. It should let the moisture between the glass of the door dissipate faster.
However, if the glass is still visibly wet after a reasonable amount of time, we recommend service. Contact Samsung’s Service Center for some assistance.
| Tips: We have a few tips to help you prevent your cooktop lamp from going haywire again. Keep our tips in mind when you’re cooking food with high moisture content. • Cover your food properly when you’re cooking it in your microwave. • Avoid blocking the vents to promote better airflow. • After cooking food in your microwave, leave the doors open to let the steam dissipate. Then, wipe it down with a clean and dry cloth. |
The vent fan automatically turns on.
Your Samsung over-the-range microwave has a vent fan that dissipates heat from your cooktop. It keeps steam and fumes away from your microwave.
Since the vent fan is temperature-sensitive, it automatically turns on if your microwave is getting too hot. It turns on by itself to prevent your microwave’s electrical components from getting damaged.
You can’t turn off the vent fan once it automatically turns on. However, it should turn off once it detects that the area underneath it has reached a safe temperature.
Solution: You can help your microwave cool down faster by promoting better airflow. Remove any obstructions blocking the air vents and maintain adequate ventilation space around your microwave.
| Tips: Keep the following tips in mind to prevent your microwave from overheating and your vent fan from automatically turning on. • Open your windows or your range hood when you’re cooking to draw steam away from your microwave and other appliances. • If you have a countertop microwave, Samsung recommends placing it on an open table for optimal ventilation. • Maintain at least 10 cm of ventilation space on all sides of your Samsung microwave and at least 20 cm on top. |
If your vent fan turns on when the microwave isn’t at risk of overheating, contact Samsung’s Support Center and request service.
The microwave is starting on its own without any interaction.
If your microwave just starts turning on by itself, you could have a problem with the main control board or the touchpad.
Solution: To fix a microwave that turns on by itself, you need professional help. Unplug your appliance and contact Samsung’s Support Center immediately.
Don’t plug your microwave back because it is a fire hazard. Wait for a Samsung professional to diagnose the problem and recommend an appropriate solution.
