• ** 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

    Jake
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LG LWC3063ST Combo Microwave / Wall Oven - Died mid microwaving

Cubs4Life

Premium Member
Joined
Jan 26, 2021
Messages
9
Location
TN
Model Number
LWC3063ST
Brand
LG
Age
1-5 years
Help! I have a 2 year old LG LWC3063 combo microwave wall oven. It was 7 seconds into a microwave cycle and the whole unit completely went dead. Display, microwave, lower oven, everything. Since then I have:

- Checked the main breaker - GOOD
- Confirmed power is coming into the unit - GOOD
- Checked the main 20A fuse (right side of upper microwave oven) - Reads 120V GOOD
- Checked continuity with the two thermal fuses in the microwave section - GOOD
- Had a repair guy come and he checked all the fuses, recommended a new PCA board
- I replaced the PCA board - NO CHANGE
- I replaced the PCB board - NO CHANGE

Other things to note, the PCA board has no power coming into it at CN64 (checked per the LG troubleshooting pamphlet). There is power to the PCB board at RL14 (120V going into the relay but nothing coming out). I feel like it has to be some sort of fuse that myself and the repair guy have missed? Any suggestions on what / where to check next? I'm going on 2 weeks with no microwave and it's starting to destroy my marriage! Please help.
 

Jake

Appliance Tech - Admin
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Messages
123,775
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McMullen Valley, Arizona
I don't know anything about microwaves, Rick is very good at them, I will ask him if he can assist you.

Jake
 

rickgburton

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I can't get anything to come up with that model number even though the number seems to be a good number.
(checked per the LG troubleshooting pamphlet)
Can you post a copy here?
 

Cubs4Life

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rickgburton

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Not the model tag, I know the number is good it just doesn't come up on any of my parts sites. Can you post a copy of the "LG troubleshooting pamphlet" you have?
 

Cubs4Life

Premium Member
Joined
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Messages
9
Location
TN
Here’s what was taped to the unit
 

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rickgburton

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OK, that's exactly what I need. Unfortunately time has not been kind to these old eyes...lol. I need a crisp clear, in focus .jpeg so when I zoom in I can read it. Most important is the wiring diagram/schematic on the top right. Maybe take a pic of 1/2 the tech sheet then a pic of the other half so they overlap a bit and I can put it together. Sorry for being a pain in the a$$. Be thankful I don't need to listen to anything...Lol. Thanks.
 

Cubs4Life

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No worries! How’s this?
 

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rickgburton

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I appreciate the attempt but I still can't see the wiring diagram very well. I'll try to find it online. However, I can read the flow chart. What's the output voltage of the noise filter?
 

rickgburton

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The noise filter is a small pc board where the power for the microwave is supplied. It probably has the 20 amp ceramic fuse on it. Input and output voltage should be 120 VAC. This is for a GE but will give you an idea what it looks like.

s-l640_001.jpg
 

Cubs4Life

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Jan 26, 2021
Messages
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Location
TN
So, for output, there’s a black and then a white and blue wire. Which should I connect up the meter up to? Just want to be certain I don’t make cx a mistake
 

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rickgburton

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Look on your wiring diagram for the CN64 connector on the main board and carefully trace the two wires (one at a time) until you get to the noise filter. Then look at the color wires.
 
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