Whirlpool Microwave Model WML55011HS2 heats for the first 20-30 seconds and then provides almost no heat for the remainder of the cook time

[FoothillsStar]

Model Number

WML55011HS2

Brand

Whirlpool

Age

1-5 years

This microwave heats for the first 20-30 seconds and then provides almost no heat for the remainder of the cook time. Put something in and you can hear it turn on and within 20-30 seconds you can hear what I think is the magnetron stop, everything else is running (fan, turntable...) then the magnetron will be energized for about 5 seconds every 20 seconds or so until the end of cook time. I've never run into this before. Ideas?

 

[FoothillsStar]

I saw another post on this model that was behaving somewhat similarly, but the poster left the discussion

 

[Jake]

Hi,

Here's the parts diagram for your model: Parts for Whirlpool WML55011HS2 Microwave/hood Combo

Rick has been out sick since Jan.12th with a serious illness, we are hoping and praying for a speedy recovery! He is very good with microwaves and I am not unfortunately.

@jeff1 is very good too, he mentions this here:

KHMS155LBL Magnetron, Diode, Both?

The microwave started making a very loud noise when the magnetron was firing and it wasn't heating food. My understanding is that this means either the magnetron or the diode is bad? The diode physically looks ok - there are no signs of being burnt or other physical damage. I tried testing the...

www.applianceblog.com

Also Rick made a diagram here that may help you:

LWC3063ST/00 LG Microwave appears to function normally, but is not heating

Hello all. I'm having an issue with the microwave in my wall oven combo. The microwave appears to function normally, but is not heating. I can hear the relays on the board working and i have checked the blower, magnetron, transformer and line filter. Any ideas? I do hear a loud pop when I...

www.applianceblog.com

Always make sure you disconnect power to the microwave first, then discharge the high voltage capacitor FIRST before you do any testing.

Use a metal ( not the shiny chrome type ) screwdriver with a insulated handle to short across ( touch both at the same time ) the terminals of the high voltage capacitor to discharge it. With the microwave unplugged.