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Tone Blair

Im DUMB and need help on Kitchenaid Microwave khms2040wss-0

9 posts in this topic

md khms2040wss-0

 

So, initially got called out on a no heat problem.

I'm not 100% but i narrowed down to hv transformer or the cap, not sure how to really test these.

Anyway, somehow we managed to blow the 20 amp fuse, I suspect we wired the switches wrong, and unfortunately we're dumb and dont fully know how to read the schematic.  We looked like a bunch of dummies for a couple hours then decided to tell her we're dummies and we need to take it to our imaginary shop (my house).

I dont even know how to tell the difference between the switches.

Also the schematic has HL, HF, CL, TT on it, im pretty sure the CL stands for cavity light and TT, turntable?

So, Appliance Gods, someone please save me!!

Thanks!!

 

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Need appliance parts? Call 877-803-7957 now!

sometimes it's better to just stop

 

you have a microwave that does not heat , so somethings burned out

 

on top of that fact

 

you may have wired a few micro switches wrong

 

now , YOU MAY HAVE A HAZARD ON YOUR HANDS , a danger to you or the appliance owner

just because you may get it going (at this point would be the worst thing to happen ) .

A microwave is nothing to mess around with if you are unsure

 

so if you can be 100% sure of your work , go at it and fix away

if you can't ....... Don't

 

the homeowner will understand if you tell him it can't be fixed

microwaves are rarely fixed anymore

Edited by Cactus Bob

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  If you decide to proceed, the best way to test for high voltage (in my opinion) is to hold a voltage test stick about 10 inches or so from the HV transformer and start the microwave. If the voltage stick goes crazy then you have high voltage and most likely a bad magnetron. AND, remember, microwaves can be killers. I can't remember the number but many people are killed each year trying to repair a microwave, even technicians. Watch your feengees.path-severe_elec_burn.jpgman-after-electric_~b13478.jpgelectrocution-danger-sign_~k1056695.jpgdanger-don-t_~k10365554.jpg

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Ok there.
So, I think i figured out why I kept blowing a fuse, which I didnt think of anything of it at the time, but......

To test the microwave, I was plugging it into a GFI, which the fridge is actually on the same circuit, and it was actually tripping the breaker too.

So i'm sure there is some sort of weird things with GFI's.

I plugged it in at my house, no GFI, and it didnt blow a fuse.

I then retested the components according to the tech sheet so graciously provided by Grand Master Funk, well at least I think I did it right.

I checked the cap for resistance and it kept gradually rising, is that normal?

I put some water in there on high for 2 minutes and the water was warm.

The mag was crackling away and I could see a little light in it, so Im kinda thinking that the mag is going bad, or completely bad all the way???

If the cap and hv trans was bad, would the mag be making any noises??

I checked for continuity on the mag, and I was getting it, but I guess that doesnt necessarily mean that its good?? Right??

I need help here guys..

What is absolutely the safest way to discharge a cap?? I read/seen a few different ways on the net, but what is the best method??

 

The customer does not want to fix it, they just want to be able to use the hood portion until they get a new one.

 

This is just for my sake now, I really would like to know how to properly diagnose these things.

 

 

Thanks for all the help!!!

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Edit: After a lot of thought I really think cactus bob has it right. If you don't understand how to work on microwaves, please don't. Its incredibly dangerous. 

Edited by RussTech

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Yea, prob right

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Been servicing microwaves for 20 years and there are spots on my face where my beard just does not grow right.  Dammit, I knew it!

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     I'm reminded of one time, a fellow tech and myself were at the shop.  He was working on a large countertop microwave and I was down the hall in the front office.  We could see each other and were carrying on a conversation, I forget about what.  I'm absolutely positive he had a few fillings in his mouth because as he was looking and talking to me his hand must have touched the high voltage diode or capacitor, discharging it.  I kid you not sparks flew out of his open mouth!  Being the trained and responsible guy I am I immediately fell to the floor, laughing my ass off.  I eventually recovered and asked him if was ok and he said yes, just scared the hell out of him.  I said, "Man, did you see sparks fly out of your mouth?"  He said no, he must have missed that.  Needless to say we both found new respect for microwaves and the awesome, dangerous, and sometimes hilarious power of the high voltage capacitor.

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