Kitchen aid micro wave change fuse - KitchenAid KHMS2050SSS Microwave Oven

First I'm not a Kitchen Aid tech.
* The fan is stuck on or the cook cycle has not completed. Either way something is wrong. Try unplug the Micro wave and let it rest for 10 seconds. Power back up and see if the fan still runs. If so then pull the plug. Don't use the M/W
* Check your warranty and call or take it to the service center.
* There are no customer serviced parts in a Micro wave.
*** High Voltage present. High Gauss Magnets present, High voltage storage device hazard present even with power off and disconnected! ***
* Be safe, call for service or get a new unit and dump this one.
Aloha, ukeboy57

open and look for blow fuses

Take your measurements and compare them to the measurements from various microwaves online, then go to the store that has the same measurements. I wouldn't use the microwave for fear of a fire.

Pc board problem its need technician

you can buy that part online kitchen aid.

Did you ever find a fix? Mine is doing the same thing!! Uggghhh!

Micro wave as the name suggests produces heat when the micro waves aimed at an object causes the water molecules inside the object to vibrate hence producing heat.The gadget responsible is the magnetron. If your magnetron is not receiving ht voltage or receiving but faulty, then your micro wave wont work please take precaution when opening micro wave due to high voltage caps that remain charged sometimes even when it is off.check the high voltage fuse/ diode and capacitor if they are fine and the step up trans former o.k then the only option is to replace the magnetron

With micro waves, this could be a number of things. They are hard to diagnose using this forum but I'll try. There are three things you can check. One being the thermal fuse. On some models, when it goes bad it put some things out. with others it puts every thing out.
if it's good, check the mag tube (Magnatron). Most of the time, it will be burned on the end if it's bad. tube. The last thing would be the fuse. It is made of ceramic and is a 20amp. It looks like a old round car fuse but it's not. It's made just for micro waves. Honestly, if the thermal fuse and the round 20 amp fuse is not the problem, you may be able to replace the micro wave cheaper than replacing the parts.
Thermal fuse $28.99.
Round 20amp fuse $1.53
Transformer $100.00.
Mag tube $87.00
Capacitor $45.00
Go to www.appliancepartspro.com and enter your model number. This will pull up every part in the micro wave and their prices. Then you will ba able to decide if you want to replace the parts. With yours being one that's built-in over the stove. These cost more and are worth putting more into. If I can help any more comment back and I'll do what I can.
Please rate solution

a microwave that is that old should be replaced!! period... for your safety... that old ,will leak micro waves into your kitchen..truly! not safe

According to the owner's manual for model KHMS155L:

To Lock/Unlock Control: The microwave oven and Timer must
be off. Touch and hold START for 5 seconds until 2 tones sound and a lock icon appears on the display. Repeat to unlock and remove the lock icon from display.

You can download the manual here:
http://www.kitchenaid.com/custserv/service.jsp

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