• ** REMEMBER! **The microwave can still shock you even unplugged!!

    ALWAYS discharge the high-voltage capacitor first if you even think your hands will come close to any HIGH VOLTAGE components.

    Jeff mentions this: Anything in the high voltage ( magnetron, capacitor, diode, wires to and from ):
    ...Use a metal ( not the shiny chrome type ) screw driver with a insulated handle to short across ( touch both at the same time ) the terminals of the high voltage capacitor to discharge it.

    From Jeff's site: http://www.applianceaid.com/component-testing.php

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KitchenAid Microwave KMHC319ESS4 Fan & light stay on with door closed, fan stops when door opens

Brian L

Jun 13, 2022
Model Number
1-5 years
This is similar to other posts, but with a little more detail so I figured I would post it. After cooking, the fan and light stays on. Opening the door stops the fan, and the light remains on. As mentioned, the microwave does heat and timer works as expected. This microwave has two sets of switches (2 in an upper and 2 in a lower bracket), with one NC and one NO in each bracket. Switches tested OK, but thought that one of the brackets might somehow be responsible by not fully closing or opening a switch.

Ended up replacing the two brackets with the 4 switches with no change. At this point I think the only viable cause is a bad relay, as I can't see how it would be a transformer. I believe the control board falls under the unit's 5 year warranty (KitchenAid customer support was vague), but I would have to get an authorized KA tech to do the service and pay labor. I found the control board for $110 and wouldn't expect a tech arriving at my house to be any cheaper with their labor. I was wondering if anyone had the exact same situation (light/fan on door close and light on door open, and switches OK) where the control board was the cause.
I just had this exact thing happen today, same model. I don't know the cause.
Hopefully @Brian L will come back to update us on how his repair went.

Here's the parts diagram for your model:

@rickgburton is very good at Microwaves, but he's been out sick for awhile, and I don't know anything about fixing them or I would help too.

That's good to hear, hopefully the problem won't return.


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