How to Repair Your Microwave
If your microwave stopped working–or is not working as it should–you may be pleased to learn that many problems you encounter can be fixed by yourself. The tools needed are basic ones you may already own, such as flathead and Phillips head screwdrivers. Even many microwave parts are easily available inexpensively online.
Working on a microwave can be dangerous. While most electrical devices immediately dispel their electricity after they have been unplugged, there is the chance that the microwave may still have live electrical parts. The U.S. Consumer Product Safety Commission (CPSC) notes that, on average, two people die per year while working on their microwaves.
The high voltage capacitor within microwaves does retain a charge, but an internal resistor is designed to automatically empty out that charge. After unplugging, let the oven sit for at least 10 minutes to make sure the charge is fully dispelled in the event of a non-functional resistor.
What You'll Need
Equipment / Tools
- Flat-head screwdriver
- Phillips head screwdriver
- Voltage detector
Which of the following supplies you need depends upon what you find through troubleshooting.
- New fuse
- New coupler
- New motor
When Your Microwave Oven Outlet Isn't Receiving Power
In this case, the microwave display will not light up. When you try to turn on the microwave, nothing happens.
Check the GFCI Outlet
According to the electrical code, outlets over kitchen counters are required to be ground-fault current interrupter style. GFCI outlets frequently trip. Unplug the microwave, press the "Reset" button on the GFCI outlet and/or in the electrical service panel at the breaker switch, plug in and try again.
Test Other Outlets
Your microwave may not be plugged into a GFCI-style outlet but it might still be receiving GFCI protection from another outlet that is GFCI-style. While not a common practice, this does adhere to electrical code in many communities. Unplug the oven, reset all other GFCI style outlets in the kitchen, plug in and see if the display lights up.
Flip the Circuit Breaker
The circuit breaker on the electrical service panel may have flipped off. Locate the service panel, then locate the breaker that correlates to the microwave's outlet. Flip the breaker off and then on again.
Test the Microwave Oven Cord
You can double-check that power is running to both the GFCI outlet and into the microwave's power cord with an inexpensive voltage detector. Touch the detector to the power cord while it's plugged into the live outlet. If it beeps or lights up (depending on the tester), this means that the cord is electrified.
When the Outlet Has Power But the Oven Doesn't
In this case, you have determined that your microwave has live power running to it, but the display does not light up and the oven will not turn on. The problem may be a blown fuse. To purchase the correct fuse, consult your owner's manual. Microwave fuses are inexpensive and readily available online.
Locate the Fuse
Unplug the appliance and access the working area of your microwave. If you have a countertop microwave, you will likely access it in the back by unfastening the metal cover. If this is a permanent, over-the-range model, you may be able to access the inside from the front.
Once inside, you will see two black wires connected to each other with a plastic casing between them. The fuse is located within this casing.
Remove the Fuse
Open the casing with a flat-head screwdriver and pull the fuse free from the two wires.
Install and Test the New Fuse
Remove the new fuse from its package, taking care not to touch the conductive metal ends with your fingers. Touch only the center area.
Push the fuse into place between the two wires and snap the casing shut.
Close the access door and try the microwave.
When the Microwave Carousel Seems to Be Malfunctioning
If your microwave fully powers up and runs, but the turntable or carousel that is supposed to rotate the food spins in jerks or does not spin at all, the issue may be with the carousel drive bushing coupler. The coupler is the 3- or 4-pronged plastic part that engages with the carousel to make it turn.
- It may not be engaging with the carousel (in which case, all you need to do is align the teeth, or it is so embedded with food and other gunk that it no longer adequately engages with the carousel teeth.
- On the other hand, the issue might be with the motor which might need replacement. While this fix may sound intimidating and expensive, it is neither. Microwave carousel motors, available online, are relatively cheap, small, and easy to replace.
Clean the Carousel
Open the door and remove the turntable by lifting it up. Grasp the coupler with your fingers (not pliers) and pull it straight up.
Clean this item in warm, soapy water, replace it and the carousel, and try again.
If this does not work, remove the coupler again. The coupler may be stripped at the bottom so that the motor's metal shaft does not engage with the coupler. Purchase a new coupler online and replace it.
Inspect and Clean the Carousel Ring
A plastic wheeled ring surrounds the bushing coupler mentioned above and supports the turntable. Check to make sure that the wheels on this ring easily turn. If not, immerse in warm soapy water, clean, replace, then try running the oven again. If the carousel still does not work correctly, proceed to the next step, replacement of the motor.
Replace the Carousel Motor
Turn the microwave on its side (for over-the-range ovens, you can access from the bottom) and remove the access panel with a Phillips head screwdriver.
- Before setting the access panel aside, you may need to disconnect a wire harness that attaches to the light. To do this, squeeze each side of the connector until the wires separate.
- Two wires connect to the motor. Slide those wires off of the motor terminals.
- Unscrew the current motor from the microwave with the Phillips-head screwdriver and remove.
- Place the new motor on the bottom of the microwave. Ensure that the flat side of the motor's shaft aligns with the flat receiving hole in the coupler. Screw the motor into place, and attach the wires to the terminals.
- Restore the access panel, plug in, and try the microwave.
When to Call a Professional
If you feel uncomfortable at all with this repair, call in an electrician for everything leading between the service panel and the kitchen outlet. For matters leading from the outlet to the microwave, call in a microwave technician.