How did I repair a family member's microwave?

First I want to give you information about the pieces that influence the microwave to turn on.

Typically equipment power failures are due to three components:

Fuse, thermostat or electronic circuit failure:

Thermostat Fuse

Circuit

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-External electrical faults:

Any high or low current in the outlet or a short circuit in the outlet may cause the fuse or thermostat to fail as a protection mode for the primary components. This is normal, but in some cases neither the fuse nor the thermostat act immediately to protect the components, which can damage the control panel circuits, causing the product to turn off.

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-Condenser fault:

The part that condenses the current emitted by the transformer, which is intended to provide the functionality for heating. This part may fail and cause a short circuit that will cause the microwave to shut down with the failure of the fuse or other components.

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-Transformer failure:

Its function is to supply the current voltage necessary for the equipment to emit the heat ripples. Part that can also cause a short circuit and therefore affect the other components.

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Microswitch failure:

These are door sensors with a push button that opens and closes. This one has a normally open button that interrupts the current flow from one terminal to another when the door is closed and 2 normally closed sensors that interrupt the current flow when the door is opened. These are located on the door opening mechanism. The main utility of the sensor is to serve as a safety feature so that the equipment does not operate with the door open. In some cases these parts are usually sulphated and thus cause short that affect the equipment.

With these brief descriptions of the parts that may have affected the fuse, thermostat or equipment circuit. It is possible to determine what is the failure of the equipment.

Now the steps I took to achieve the repair.

As a first step I proceeded to remove the special screws on the back, in this case the screwdriver was also special and had a star shape as shown in the picture:

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When I removed the screws, the cover could be removed and I could see the different components on the side of the equipment.

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• The most important thing to start any overhaul is safety, one of the components that holds the microwave energy charge is known as a capacitor. It is extremely important to discharge current into the piece. To do this I took the clamps that have rubber insulation on the handle and on the 2 poles of the piece shown in the image I placed on both ends of the clamp, this caused a maximum current flash (in some cases there is no flash or the flash is minimal), and when performing this step was safe to overhaul.

As it was already safe to work with the microwave. I went to check the fuse, but found that I didn't have it, because they had already checked it and removed the part. As we can see in the image the space is empty and in the circuit where the piece should be, it shows the indications that the fuse is 15 amps 250 volts (in case the fuse is present, it is measured in continuity with the tester and this way it is verified if it is faulty).

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• It is necessary that the door is opened only when the equipment finishes the time or you can press the cancel key so that the time ends earlier than expected and only then the door can be opened. In cases contrary to this advice they will only cause their microswitches to sulfate and failures to occur.

  
  
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  This has been all for today friends, as a professional repairer I hope that the information provided has clarified curiosities and doubts.

  
  

  Original content from
  @jose27117