Because microwaves are quick, easy and convenient to use, they are often the most popular cooking appliance in many households. Because of this, they can be susceptible to breakdowns. Instead of taking your microwave to an expensive repair service when it is not working, you should follow these two tips first. Perhaps you’ll be able to save yourself time and money if you are successful in fixing your microwave yourself.
Simple Repair Tip #1: Test Your Fuse and Replace If Necessary
If your microwave is not functioning, the problem could be with your fuse. The fuse acts as a safety device which monitors and prohibits the flow of electricity to the microwave when the current is too strong. The fuse has to be in working order for it to pass the electrical current on to the microwave, so failure here is a common culprit for a non-working microwave.
Unscrew and remove the outer cabinet that houses the microwave, and locate the fuse by following the power cord inside the unit. If you see burn marks on the fuse or it is completely black, it is most likely blown and will have to be replaced. If you happen to have an ohm meter handy, you can test the fuse by seeing if current can pass through the fuse. If the meter reads zero ohms, then current is passing and your fuse is okay. If it the ohm reading is infinite, then no current is flowing through and your fuse failed the test.
To remove the fuse, just simply remove it from its holder. You can snap it in or out easily. You can call the manufacturer to get the right part number for the fuse, then order a new one online or call a local electronics or appliance store to make sure they have one available for you to pick up.
How much are fuses? Typically they range as cheap as $5-$20.
Someone who is halfway handy could have removed the fuse in 5 minutes and ordered a new fuse in another 5 minutes. If purchased locally, a half hour later they could have the new fuse installed and the microwave in working condition. If you took it to a repair shop, you would have waited at least a day or two for the repairman to get around to it and been charged as little as $50 if you’re lucky.
Simple Repair Tip #2: Test the Door Switch and Replace If Necessary
The door switch is another part that acts as a safety device, not allowing the microwave to function if the switch is triggered (i.e. the door is opened). A non-working switch will prevent your microwave from functioning.
First make sure the latch inside the door itself is not missing or damaged. The latch activates the switch when the door is in the closed position. The latch looks like a prong or hook, so make sure it is there and does not look damaged. Otherwise, it will most likely need to be replaced professionally since it can be difficult to remove the inner seal off the door, or the door itself may need to be replaced.
If your latch and fuse are fine, then most likely your door switch is the problem. This is the most difficult and last thing you should check. You’ll find your door switch mounted on a bracket where the latch would make contact. To test the door switch, you will need an ohm meter. First remove the wiring harness leads from the terminals, and then test the switch for continuity. To help you with this, let’s look at the anatomy of a door switch. It has three terminals and they are labeled as follows:
• N.C. Terminal – Normally Closed
• N.O. Terminal – Normally Open
• COM Terminal – Common Terminal
First test the resistance between the COM and N.O. terminals – you should have infinite resistance. You’ll see a little actuator button and if you press that down (which simulates the door closing), then the resistance should go down to zero, indicating current is flowing. Repeat this test between the COM terminal and the N.C. terminal, but the results should be the opposite. You should have zero resistance at first, then when you press the actuator (simulating opening the door) it should jump to infinity, indicating no current or power. If one or both of these scenarios doesn’t happen in your test, then the switch is broken.
When you replace the switch, be sure to use the same type of switch as the original – call your manufacturer to get the correct part number and purchase the same replacement part. Remove the bracket that houses the switch from the microwave, and remove the old switch from the bracket and replace with the new one. You should be able to find a new switch for less than $20. If you took it to a service shop you would probably pay at least $100 between diagnosis and repair.
So these two tips will hopefully save you from an expensive trip to the repair shop, so you should at least attempt to fix a non-functioning microwave yourself first. You won’t do any further damage to it, and remember, always make sure the microwave is unplugged before operating on it.