Frustrated that you’re unable to warm or prepare your favorite dish using the microwave?
Does your microwave’s fuse keep blowing? Then this post can help.
It lists the possible reasons why the replacement fuse keeps blowing and what you can do to fix it.
Note: There is a high risk of electric shocks when repairing a microwave. Some components retain dangerous voltages even after the microwave is disconnected from the wall outlet.
Do not proceed with the repairs unless you have the skills to safely work and repair microwaves. Consult a qualified microwave technician.
Why Does the Fuse Keep Blowing?
If the microwave fuse keeps blowing, it may be because:
The High Voltage Capacitor in the Microwave is Shorting
The capacitor is located inside the microwave. You’ll need to safely remove the microwave housing to access it.
Consult the microwave’s service manual for its location as it may be different for your specific microwave make and model.
Replace it with another of the same capacity (uF) and type it as the original. One fitted, replace the fuse, and check if the fuse stops blowing.
Should You Use a Fuse with a Higher amp rating?
No, always use the recommended fuse rating. Do not attempt to use a higher amp fuse as a way to stop the fuse to blow.
Doing so, risks exposing the microwave circuitry to larger and potentially damaging currents than it is designed for that may even cause a fire.
Always fit a fuse with the recommended current rating (amps) and type.
Signs that Fuse has Blown
With the inbuilt fuse blown, the microwave will usually not be able to power up – the display stays blank, the interior light does not come on and there is no beeping sound when the display buttons are pressed.
The fuse blow may be instant or when you press the microwave START button.
Where the Fuse Is Located?
The fuse is located inside the microwave housing on the power circuit. Refer to the microwave’s schematic.
Note: Confirm that the microwave power cord is not damaged, that it is firmly plugged into the wall outlet and there is power available at the outlet.
You may also be interested in this post: Why the microwave display is blank and what to do
Should you Repair a Microwave? Is it Worth it?
This depends on the type of fault, and associated costs of parts, and labor. If the costs of repair are minimal, perhaps it is a power cord that needs to be replaced then perhaps it is worthwhile repairing.
If on the other hand, the repair costs are comparable to buying a new one which goes for between USD100 – 200 for a 1.6 cu. ft microwave at current market prices then it’s probably better to buy a new one that comes with a 12-month warranty.
What Causes the Microwave Fuse to Blow when Opening the Door
It could be a broken or faulty latch board. The latch board holds the microwave door latches and synchronized the release of the door latches when the door is opened or closed.
Over time, these latches wear down and the latch board needs to be replaced.
Why Microwave Fuse Blows on Pressing Start
There’s an internal short in the microwave. This may be down to a faulty microwave high voltage capacity that needs to be replaced.
If the microwave input fuse keeps blowing then there’s a short. This short is sometimes caused by a failing high voltage capacity inside the microwave. It will need to be replaced.
Note: Contact a qualified microwave technician or only conduct or attempt repairs if you have the skills and the necessary safety knowledge to safely work with microwaves.