Microwave will not heat

Q - The microwave makes a loud "hum or buzz" noise but will not heat up the food?
A - 9 times out of 10 this is usually this is a bad magnetron, the other time is sometimes a bad high voltage diode. See components section.
Q - My microwave is running and sounds like it is working but will not heat up anything.
A - Many thing can do this but, common things are....loose high voltage wire.....poor solder joint on board.....magnetron.....power relay.....
 Q - The microwave display counts down and the inside light is on,  but nothing is heating and the fan is not running.
A - This most commonly is a bad door switch, other possible problems are a faulty relay or solder joint on the power module, but a bad door switch is most common.
Q - The fan in my microwave oven is not running will this hurt my microwave?
A - YES, the fan cools the magnetron and electronics, take the microwave in for service, most fans are not too expensive to replace.
Q - My microwave blows the fuse inside itself as soon as I push the start button.
A - Usually a shorted high voltage capacitor...see components section.