FIXED Model MC17J8000CS Runs but NO HEAT

[Bill1985]

Model Number

MC17J8000CS

Brand

Samsung

Age

1-5 years

This is a 2017 model , always has worked great until Tuesday night , suddenly NO heat and sounds louder now then before when running.. I work on cars , atvs , sxs , washers , dryers , never messed with Microwave so this is all new to me , anyone have any ideas where to even start ?

 

[Bill1985]

No one has any ideas ?

 

[Wx4usa]

Make sure you unplug the microwave and discharge the capacitor. Sounds like possibly a bad diode.

 

[Bill1985]

Make sure you unplug the microwave and discharge the capacitor. Sounds like possibly a bad diode.

So , I've tested just about everything that I can , I've tested the Capacitor , transformer , 3 door switches , 5 thermal cut offs and Diode , I found 1 thermal cut off on the base of the microwave , there is 2 beside each other and the one no Continuity but not sure if all 5 are supposed to or not , the one beside it with Red wires coming off it seems to be intermitent , sometimes it has continuity and other times it dont so without knowing of all these should have continuity or not I don't know where to go from here , I'm assuming one of the thermal cut offs would be open because one of them controls the fan if it gets hot , anyone have any idea which ones should have continuity and which ones shouldn't? Diode tested to be working properly as did everything else

 

[Wx4usa]

So if one was intermittent, at room temperature, that’s not normal.

 

[Wx4usa]

Your model has a hood TCO with no bearing to heat. It’s open at room temp. Convection TCO closed at room temp. Cavity TCO closed at room temp. Magnetron TCO closed at room temp. Bottom TCO closed at room temp.

Rule out the bottom TCO because it kills power to the microwave. Rule out the hood TCO because it just operates the fan. Rule out convection TCO because it just kills power to conventional elements.

If all else checks ok, I’d focus on the board relay and look for 120v from that relay. If you have 120 V there, it is likely not the transformer, and you checked the capacitor and diode so that leaves the magnetron.

 

[Bill1985]

I'm going atttach a link for you to see the 2 TCO's on the ( right side of base ) , the one closest to the edge of base is the one that's open and the one directly beside it ( held down by the same screw is the one that was intermittent when I tested it yesterday , I'm learning as I go so thanks for your patience . The one red wire coming off the TCO I mentioned above that was Open , there was a bare spot on the 1 wire like it had rubbed something so if you look close you can see it - the bare spot , i fixed that and not sure If this is what caused the issue or not to make it not heat the food...
I didn't see a spec sheet listing everything inside microwave but I wasn't looking for it and not sure where they'd put it honestly..

 

[Bill1985]

 

[Wx4usa]

The bottom TCO (2 black wires) is in-line and will kill power to the microwave. At room temp it will have continuity. It is not resettable. Its marking are 120/0. 248/32f.

The hood TCO (2 red wires) has no continuity at room temp. It is resettable. Its markings are 40/70. 104/158f

I don’t think either one will allow startup and no heat if failed. I don’t think these are the issue.

Not sure what would cause part of the insulation to be damaged.

 

[Wx4usa]

If you hit start and fan starts and light comes on and no heat, turn it off and take the connector off of the monitor interlock switch. Place you meter leads into each of these wire connections you just removed. Hit start and see if you read 120v across these two switch wire connections. If not, replace the main control board. If, yes and the diode and capacitor test good, replace the magnetron.

 

[Bill1985]

If you hit start and fan starts and light comes on and no heat, turn it off and take the connector off of the monitor interlock switch. Place you meter leads into each of these wire connections, place a cup of water inside. Hit start and see if you read 120v across these two switch connections. If not, replace the main control board. If, yes and the diode and capacitor test good, replace the magnetron.
View attachment 70427

Ok , when I get home tonight I'll mess with it again , ( I really appreciate any help so far ) , I'm going see if I can find the service information sheet inside somewhere also , where do you suggest to get the parts if i find i need any ? Trying to find a good (clear ) parts diagram for these has been tough , I'm use to Atv and car parts diagrams and they're layed out in a way that makes it easy to find parts..
Thanks

 

[Wx4usa]

I just re read your original post. If it sounds louder and no heat, that usually indicates a failed diode or capacitor.

 

[Bill1985]

Magnetron is toast... I don't know how I missed it the 1st time I tested it last weekend but then again , this stuff is new to me so I'm learning as I go but from the test i did tonight , I'm 100% sure it's bad , terminal to terminal its good but terminal to body BAD.... I'm ordering a new one tonight.
Thanks again for all your help , for being patient with me , I really appreciate it..
Ill re comment once I get the new one installed and it's working again to update the post...

 

[Wx4usa]

Very good Bill! Keep us posted!

 

[Bill1985]

Very good Bill! Keep us posted!

Well it's fixed and working , new Mag did the trick so thank you for all your help and I definitely learned a lot from this.

Magnetron OM75P(10)ESHL

 

[Wx4usa]

Bill, that’s so good to hear. I’m glad the magnetron fixed it.

 

[Bill1985]

Update. It's still working great.

 

[Wx4usa]

Awesome Bill