Modern microwave ovens are designed to last for at least five years, but you can still experience issues with them. Avoid paying for costly repairs and service technician fees, and fix minor problems with your microwave oven. Do not attempt to perform major repairs on a microwave oven as these are complicated and can be dangerous for most consumers. Always unplug your microwave before attempting any repairs.
Not Turning On
If the microwave won't turn on at all, check that it's plugged into a live outlet. Test the outlet with a lamp. Examine your household circuit breaker, and reset if tripped. Look at the home fuses, and replace the fuses if they have broken wires or are black. Completely close the microwave door, and choose a microwave setting. Verify that you are selecting a cooking setting and not setting the timer. If the door doesn't completely close, clean the door gaskets. If the microwave doesn't have any heat, but it runs, examine the internal door switch, and replace if corroded or burnt out. Call an authorized microwave technician if you experience any other power issues.
If you see sparks in your microwave, stop the microwave, and remove any metal objects, including aluminum foil or cookware with gold or silver lining. Arcing looks like mini-lightening storms in your microwave. This is due to food or liquid buildup, which causes burn spots on the interior of your microwave. Sand out burn spots on the microwave, and use microwave interior paint to cover up the section that you just sanded. Replace the wave guide if it has burns on it.
The turntable is the plate that rotates your food. If the turntable isn't moving, verify that you have correctly placed it on the carousel beneath it. Clean the bottom of the turntable and all of the carousel components if it still won't turn. Check the carousel motor by removing the turntable and the bottom of the microwave. The motor is located right beneath the turntable carousel. If the motor is corroded or burnt out, replace it.
A microwave can interfere with surrounding appliances. Move the microwave away from these other appliances, and check that the microwave door is completely closing. If not, clean the gaskets, or replace the door if it's warped. The microwave may emit an odor or smoke when you first use it. This is normal and will disappear after using the microwave a few times. If the microwave has non-consistent cooking problems (i.e. not starting one time, but starting after a few seconds), then you have an issue with its circuitry. Check all of the circuitry, and look for loose connections. Replace or re-solder these connections.