Charles R Kingsport , TN February 17, 2024 Appliance: Model WHIRLPOOL LOW PROFILE MICROWAVE Our microwave wasn't heating it just made a very loud humming noise. I tested the diode and the magnetron, and found the magnetron was grounded and the diode was open. Replacing the magnetron was the hardest part, because in the low profile microwave there's not a lot of room. I had to slide the transformer out to make room to get the magnetron out! Read More... Do-It-Yourself Rating: Repair Time Estimate: 1-2 hours Tools: Screwdrivers