• ** 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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FGMV175QFA Frigidaire Microwave Won't Turn On

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
Model Number
FGMV175QFA
Brand
Frigidaire
Age
1-5 years
The display screen is blank and not lit up. I tried plugging it into another plug that I know works. Where do I start for trouble shooting?
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
I went a little further and discovered I have a blown fuse. Can I take out and replace the fuse without discharging the high-voltage capacitor? What fuse do I need to replace it with? Is there anything else I need to do other then replace the fuse?

Thanks
 

Jake

Appliance Tech - Admin
Staff member
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Messages
110,908
Location
McMullen Valley, Arizona
I don't work on microwaves, I'll see if Rick can help you.

Jake
 

rickgburton

Appliance Tech - Moderator
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Messages
38,696
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Murray, Utah 84107, United States
Sorry, I missed this one.
Can I take out and replace the fuse without discharging the high-voltage capacitor?
Yes
What fuse do I need to replace it with?

Is there anything else I need to do other then replace the fuse?
These fuses do wear out but more often that not, something caused the fuse to open. Sheck for a short between the fuse and ground.
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
Thanks for the response. How do I check for a short between the fuse and ground?
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
Yes I have a Multi meter. I just don't know the spot I should check? Where should I put the leads?
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
So I replaced the fuse and it worked for like a month. However it blew another fuse. So I assume there is another problem causing it to blow fuses.

On a earlier post I was told to check between the fuse and ground for a short. With the picture included can you tell me where I should touch my multimeter to?? And the setting I should place my meter on?

thanks
 

Attachments

rickgburton

Appliance Tech - Moderator
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Set your meter on the lowest ohms scale, R X 1 and check from each side of the fuse to the screw holding the green and yellow wire to the frame.
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
I tested it with the blown fuse still in place. When I test the left side of fuse I get numbers that jump around. When I test the right side of the fuse the microwaves display screen flashes on and off. Does this info help with anything ?
 

rickgburton

Appliance Tech - Moderator
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Murray, Utah 84107, United States
Fuses sometimes just wear out. Go ahead and replace it and see if it works OK.
 

rickgburton

Appliance Tech - Moderator
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Messages
38,696
Location
Murray, Utah 84107, United States
I’ve replaced 3 fuses in past 2 moths.
I only read where you replaced one fuse in the last month. Remove the control panel and check the door switches for continuity by opening and closing the door. The latch bracket that holds the three microswitches might be out of adjustment or maybe the screws that hold the latch bracket need tightening. One of the microswitches is called the monitor switch or sometimes called a "deadman" switch. It's designed to keep the microwave from working if the door is open by shorting L1 and N together and blowing the fuse. When you open the door the primary microswitch opens and kills the power to the monitor switch. If the monitor switch closes before the primary switch opens the fuse opens. It looks similar to this. The switches fit on pins and clip into the switch holder. Make sure none of the pins are broken and the screws that hold the switch holder are tight
C-door switch assy.jpg
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
The only switch I get a read out on the meter is the middle switch. The top black switch doesn’t register and the bottom gray switch doesn’t either.
DD7AC84D-2715-4649-AEF3-257734AFB4AA.jpeg
 

b1gdog83

Premium Member
Joined
Dec 24, 2019
Messages
64
Location
Boca
Ok let’s see if I did it right this time. I reinstalled the door switches and tested them by opening and shutting door with the following results:
Top black switch- continuity when door closed
Middle switch- continuity when door open
Bottom switch- continuity when door closed.

I also noticed the bottom 2 switches seem loose in the door switch bracket. I took a video of what I mean.

 
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