[jaguilar]

I turned the microwave on and heard a pop followed by a humming sound. Now it doesn't heat. I have power, the light comes on, the dish rotates along with a humming sound, no heat. I was thinking that maybe a fuse blew so I removed the panel but did not see any fuses. HELP!

[MicrowaveDisplaycom]

The pop usually indiactes a blown high voltage rectifier diode.

The humming could be normal, but if it's louder than usual it may mean the high voltage transformer or the magnetron has failed.

You can find helpful exploded view diagrams and order parts by entering your model number here: Appliance Parts Pros.com Discount Appliance Parts – Appliance Repair Parts

[Admin / APP Team]

The loud pop does usually indicate a bad rectifier. Make sure to 1. Turn off power to the microwave first and 2. discharge the capacitor before attempting any repairs.

- Replacement rectifier

[jaguilar]

So this does not sound like an easy job, what do you think? would it just be easier to buy another?

[Admin / APP Team]

Actually, it's a fairly simple job, as long as the safety rules are followed re: disconnecting the power and discharging the capacitor. But, if you don't feel comfortable working on a microwave, please don't. Getting shocked from a high voltage capacitor could mean serious heart problems or even death.

Rectifier is number 1 on this diagram and capacitor is number 2, right behind the control panel.

Here is a page that among other things shows how to discharge a capacitor. It's a long page and has lots of info on it, so I would suggest doing a search for the phrase How To Discharge The High Voltage Capacitor (click Control and F for search while on that page).

[bheinle]

How do you know if it's the rectifier or the cap? I did 12volt for alittle over 9yrs and have seen some caps go bad. Nothing internally looks bad here. Thanks

[MicrowaveDisplaycom]

It's almost certainly not the capacitor.

When a high voltage capacitor fails, it almost always shorts.

If that's the case, the fuse would blow when you cook.

You can visually inspect the diode to see if it has a pit or hold blown out the side.

And you can measure it to see if it's shorted.

With a normal meter, it shoudl read open. If it reads low or near zero, it;s shorted.

Again see this link for parts.

Here's a guide with illustrations for testing the diode.

[MicrowaveDisplaycom]

I meant "hole blown out the side", not "hold".

[bheinle]

Thanks understood the hole. Now does the cap need to be discharged before taking a ohm reading? Didn't see any holes in the diode, but they dont give you a lot of area for working.

Didn't see the link at the bottom. Got it. Thanks