Frigidaire Microwave Keeps Blowing Fuse (8 Fixes Shared!)

Having a working Frigidaire microwave hugely depends on a working fuse. Sometimes, however, a Frigidaire microwave keeps blowing fuse, and it just won’t stop, and you’ve to wonder why. 

A Frigidaire microwave won’t stop blowing its fuse because of a power surge, circuit overload, faulty power outlet, incorrect installation or fuse type, failed door switch, loose metal objects, or a defective component. 

The defective component in such a case could be the high-voltage capacitor, magnetron, high-voltage transformer, or diode. Due to the potential of an electric shock, handling the mentioned components without prior experience is not advisable, and that’s where an expert comes in. 

However, you can handle other issues as they are pretty straightforward, and I will show you how to do them. We’ll examine how these issues will cause the fuse to overheat and how you can remedy them.

But first, let’s look at the microwave fuse’s role, the types, and how to check if it’s blown and replace it. Here we go!

Frigidaire microwave keeps blowing fuse

In a rush? Below is a quick guide on troubleshooting a Frigidaire microwave that keeps blowing its fuse. 

Frigidaire Microwave Keeps Blowing Fuse – Quick Troubleshooting Guide 

Likely Reason Fix 
1.Power Surge Reset the circuit breaker first, then replace the fuse 
2.Circuit Overload Plug in your microwave in a dedicated circuit if it’s on a shared circuitry 
3.Faulty Power Outlet Replace the power outlet 
4.Wrong Fuse Installation Reinstall the fuse correctly according to the manual 
5.Wrong Fuse Type Replace the wrong fuse with a matching one 
6.Failed Door Switch Replace the door switch if it shows some resistance on a multimeter but lacks continuity 
7.Loose Metal Objects Tighten loose screws and remove any other metal objects from the microwave 
8.Defective Component (Capacitor, Magnetron, Transformer, or Diode)Ask for an expert’s help to check these components for faults and replace them 

About the Frigidaire Microwave Fuse

The work of a microwave fuse is to cut off an excessive power supply to protect the microwave from blowing up. 

So, instead of the microwave blowing up, the fuse blows up. But once that happens, the microwave cannot run until you replace its sacrificial protector, the fuse. 

Note that microwaves have different types of fuses, which you can check on your manual, but three of the commonest are:

  • Line fuse 
  • Thermal fuse 
  • Thermoprotector 

All these fuses perform the same job, and that is sacrificial protection. They blow up on behalf of the microwave and need replacing. 

But why replace the fuse first without knowing what caused it to blow up? That’s going to be our subsequent discussion. But first, let’s see how you can test a faulty microwave fuse. 

How to Test the Frigidaire Microwave Fuse and Replace It? 

Note that you’ll need a multimeter device to check if you have a blown-up fuse. Once you’ve it, follow these steps to test if the microwave fuse has continuity:

  • Power off the microwave and put it out of the power source
  • Gently unscrew the access panel to access the fuse 
  • Use your manual to determine the fuse’s location, especially the thermal fuse, line fuse, and Thermoprotector 
  • Probe the multimeter into the fuse to check if it has continuity (no resistance)
  • If it does, then that confirms it’s okay, but if it doesn’t, you should fit in the replacement fuse 

Before replacing a faulty microwave fuse, you should first find out why it blew in the first place. If you don’t, it’ll continue blowing up.

Why does my Frigidaire microwave keep blowing fuses

But Why Does My Frigidaire Microwave Keep Blowing Fuses?

Your microwave keeps blowing its fuse or fuses because of any of these eight reasons:

1. Power Surge 

The microwave fuse is designed to blow up when excess current goes through the appliance circuity. So, it doesn’t surprise me that this is the first consideration. You can know if it’s a power surge if you also have a tripped breaker. 


Reset the breaker and replace the fuse once you test it and confirm it’s faulty. If the breaker continues blowing up and the breaker keeps tripping, you should call a microwave technician. 

2. Circuit Overload 

It’s generally a bad idea to plug your microwave into a shared electric circuit. If you do, there is a chance that the plugged-in appliances may overwhelm the circuit, causing the fuse to blow up. 


Ensure you have a dedicated circuit for your microwave to prevent a circuit overload. If you don’t have it, ask an electrician to set up one.

3. Faulty Power Outlet 

Your microwave may also blow up the fuse because of a faulty wall outlet. This is usually the most straightforward check since you only need to plug in the microwave in another working outlet. 

The previous outlet could be faulty if the fuse doesn’t blow while the microwave is plugged into the new outlet. But to confirm, plug another appliance into the power outlet you suspect. 


Once you confirm you have a defective power outlet, replace it. It can be DIY if you are handy or call an expert technician. 

4. Wrong Fuse Installation 

The connectors must face the correct direction when installing a new microwave fuse. If they don’t, then the fuse is likely to blow up. For this reason, checking your Frigidaire manual for directions is advisable before fitting in a replacement. 


You may revisit your troubleshooting manual to see if the fuse connection is correct. If not, remove the fuse and fit it in a replacement fuse. 

5. Wrong Fuse Type 

The fuse may also blow up if it’s the wrong type. You can tell if its amperage rating is not similar to the original fuse’s. 

The wrong fuse will blow up, and the amperage could prompt a fire or damage the microwave’s wiring. 


Replace the microwave fuse if it’s the wrong type. This time, ensure you get a replacement that matches the original’s specs. 

Frigidaire microwave fuse

6. Failed Door Switch (Frigidaire Microwave Keeps Blowing Fuse When the Door Closes or Opens)

If your Frigidaire microwave won’t stop blowing up its fuse when you open or close the door, the problem is likely to be a failing door switch. 

The door switch is slowly wearing down or could be stuck or broken due to rough usage. The microwave usually won’t start if the door switch is defective. 


Using a multimeter, consider checking if the microwave has continuity (no resistance). If the switch lacks continuity, replace it before replacing the blown-up fuse. 

7. Loose Metal Objects 

If loose objects such as screws or other metal pieces are in the microwave, they could short-circuit it and blow up the fuse. 

So, this requires you to visually inspect the microwave for visible metal objects and disassemble it. 


Check if there are loose metal pieces or screws and remove them. You may, however, need to tighten the screws if they are only loosely attached.

8. Defective Component 

Lastly, your Frigidaire microwave could be blowing its fuse because of a defective part such as the:

  • High-Voltage Capacitor – The high-voltage capacitor and the microwave diode convert the transformer’s output to DC (direct current) and doubles the voltage. Once it fails, however, it’s unable to do that and may cause the fuse to blow up.
  • Magnetron – The magnetron generates microwave frequency (for heating food) from high current and high voltage DC. It may, however, burn out to stop the microwave from heating and, in the process, blow up the fuse. 
  • High-Voltage Transformer – The high-voltage transformer stores the high voltage that the microwave emits. If it’s faulty, the microwave won’t contain the high energy emission, and the fuse is the component to take the hit. 
  • Diode – As mentioned earlier, the diode works with the high-voltage capacitor to convert the transformer’s output to DC, amplifying the voltage to about 5,000v. It may, however, burn out and cause the fuse to blow up too. You can tell a bad microwave diode if it doesn’t show any continuity when you probe it with a multimeter.  


Replacing any of the above components is recommendable because they prevent your Frigidaire microwave from heating. Ask, however, for a microwave expert’s help because of the danger of electrocution.

Frigidaire Microwave Blows Fuse When Started

If your Frigidaire microwave blows up its fuse when you start it, the issue is likely to be any of these:

  • Wrong fuse – Microwave fuses have different ratings, so matching the original fuse is essential. If not, the fuse won’t stop blowing up. 
  • Wrong installation – If the wires are installed incorrectly, your Frigidaire microwave may blow a fuse when you press start. 
  • Component failure – The reason could be a shorted high-voltage capacitor or a failed magnetron, high-voltage transformer, or diode 
Frigidaire microwave blows fuse when started

People Also Ask 

1. Is There a Fuse in A Frigidaire Microwave?

Yes, there is a fuse in a Frigidaire microwave. In fact, there are several, but the commonest include line fuse, Thermoprotector, and thermal fuse. Their job is to protect your microwave from overheating.

2. Why Does My Microwave Keep Blowing Fuses?

Your microwave keeps blowing fuses because its door switch is defective, there’s a power surge, or the circuitry is overloaded. Also, consider that the fuse might be wrongly installed or the wrong type.

And if that’s not it, check the diode, magnetron, capacitor, and transformer for fault. 

3. Can I Use a 20-Amp Fuse for My Microwave?

Yes, you can use any 20-amp fuse on your microwave if its amperage rating is similar to the one you are replacing. If not, it won’t be compatible with the microwave, and the fuse may blow up severally. 

Closing Thought:

Now you understand why your Frigidaire microwave keeps blowing fuse. Start by checking if it’s a power surge, circuit overload, defective power outlet, incorrect fuse installation, or wrong fuse type.

Then consider a faulty door switch, loose metal pieces, or a defective high-voltage capacitor, high-voltage transformer, or diode. One of these reasons is why your Frigidaire microwave fuse won’t stop blowing and is fixable.

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