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Old 07-09-2019, 10:39 PM   #21
budm
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Default Re: Main board Magnavox 32ME402V/F7

BTW, see how to read parts map of the main board.
Right now I cannot find the schematic of the TV so that C3214 I refer to in the other 2 links provided may not be the same as C3214 as used on your main board, that is why you need to test as suggested in post 8 first.
We need to see meter so I can make sure you set it properly to read resistance.
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Basic LCD TV and Monitor troubleshooting guides.
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Inverter testing using old CFL:
http://www.badcaps.net/forum/showthr...er+testing+cfl

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TV Factory reset codes listing:
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Old 07-09-2019, 11:48 PM   #22
beuknowsdiddly
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Default Re: Main board Magnavox 32ME402V/F7

First, here's the piece of crap meter I got. Doesn't even beep for shorts.

https://www.amazon.com/Crenova-Auto-...s%2C162&sr=8-4

If that's not good enough, just let me know and I'll get a better one.

It looks like the cap is from C3828.

Here's a picture of where I pulled it from. I thought maybe because it was near that 330 coil it's possible, as that was where that guy pulled his from on that youtube video.

How do I check DC resistance on that cap?
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Old 07-10-2019, 10:05 AM   #23
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Default Re: Main board Magnavox 32ME402V/F7

That meter is fine. You do not use continuity for checking for shorts since some meter will beep with continuity as high as 50 Ohms, use Ohm mode to check the resistance of the component.
1) TV is NOT plugged into the outlet.
2) Have all boards connected back together
3) Set meter to Ohm mode, if you do not know how, read the user manual.
4) Keep Black probe of the meter on the metal chassis or on jumper wire J106 (GND) on the power supply board.
5) Put Red probe of the meter on the Cathode (banded marking) of diode D653, take pictures of the meter screen showing the resistance reading.
6) Move Red probe of the meter to the Cathode (banded marking) of diode D651, take pictures of the meter screen showing the resistance reading.
BTW, you know what the diode is and know which is Cathode which is Anode, correct? If not do the search to learn about diode and how they are marked.
I am using picture from Shopjimmy as the reference: https://assets.shopjimmy.com/media/c...1fg024-top.jpg
Regarding to C3828 resistance check, just put meter is Ohm mode and put the probes of the meter on each end of the cap, it does not matter which probe goes to which end of the cap since it is not polarized cap, report the reading.

Last edited by budm; 07-10-2019 at 10:08 AM..
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Old 07-10-2019, 08:17 PM   #24
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Default Re: Main board Magnavox 32ME402V/F7

So I'm thinking I have to deal with that C3828 I took out first. Measured off the board and it just reads 0.L Then I soldered it back and it reads 85 ohms.
It's strange though because I know it's not polarized so shouldn't it read the same either way? One way reads 85 and the other reads 65. Is that normal?

I still need to take the tv apart and remove the new board and replace it with this one to continue following your troubleshooting instructions. Crossing my fingers I don't screw anything up now that it's working with the new board. lol
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Old 07-10-2019, 08:29 PM   #25
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Default Re: Main board Magnavox 32ME402V/F7

Quote:
Originally Posted by beuknowsdiddly View Post
So I'm thinking I have to deal with that C3828 I took out first. Measured off the board and it just reads 0.L Then I soldered it back and it reads 85 ohms.
It's strange though because I know it's not polarized so shouldn't it read the same either way? One way reads 85 and the other reads 65. Is that normal?

I still need to take the tv apart and remove the new board and replace it with this one to continue following your troubleshooting instructions. Crossing my fingers I don't screw anything up now that it's working with the new board. lol
Showing OL is fine for that cap. there are other components connected in parallel with the caps, so the resistance reading may not be the same in both directions. The resistance you are getting right now may or may not be related to the problem you have.
BTW take the resistance reading as instruct with new main board in place so you will have comparison reading between old and new board. You can also check the resistance of the C3828 of the new board to see what you get.
And since I show you where C3214 is, you can also check the resistance of that cap now to see what you get.

Last edited by budm; 07-10-2019 at 08:34 PM..
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Old 07-10-2019, 08:40 PM   #26
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Default Re: Main board Magnavox 32ME402V/F7

On it! Thank you!
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Old 07-10-2019, 09:03 PM   #27
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Default Re: Main board Magnavox 32ME402V/F7

OK, I look at the main board layout, you can do resistance testing of the bad main board without having it connected to the power supply board.
Check the resistance between point 'A' and 'GND' as marked in the picture in both directions, this test the 21V power supply line.
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Old 07-11-2019, 12:12 AM   #28
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Default Re: Main board Magnavox 32ME402V/F7

I'm not sure what you mean by "both ways" you want me to put the red probe on ground and the black on A also?

The normal way black to ground and Red to + I get 14.7 ohms. This is the bad board NOT plugged into the power supply.

Here's a pic of the same spot on my board if it matters.

When I test the good one which is plugged into the power board I get 11.

and when I test that C3214 I get 1.4 unplugged from the power board.

The other good one reads .257 plugged in to the power board.
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Last edited by beuknowsdiddly; 07-11-2019 at 12:36 AM..
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Old 07-11-2019, 09:46 AM   #29
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Default Re: Main board Magnavox 32ME402V/F7

[QUOTE=beuknowsdiddly;904952]I'm not sure what you mean by "both ways" you want me to put the red probe on ground and the black on A also? Reply: Yes.

The normal way black to ground and Red to + I get 14.7 ohms. This is the bad board NOT plugged into the power supply.

Here's a pic of the same spot on my board if it matters.

When I test the good one which is plugged into the power board I get 11.

and when I test that C3214 I get 1.4 unplugged from the power board.

The other good one reads .257 plugged in to the power board.[/QUOTE]

1) The 14.7 Ohms reading is not right. What do you get when do the same test with the good board (not connected to power supply board).
2) "and when I test that C3214 I get 1.4 unplugged from the power board." Is that 1.4 Ohms. 1.4 K Ohms, or 1.4 M Ohms? Show us the pictures of the meter display.
3) "The other good one reads .257 plugged in to the power board.[/QUOTE] Is that .257 Ohms, .257 K Ohms, .257 M Ohms? Show us the picture of the meter display.

Last edited by budm; 07-11-2019 at 09:47 AM..
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Old 07-12-2019, 12:08 AM   #30
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Default Re: Main board Magnavox 32ME402V/F7

Okay I'm sorry.

1) No matter how many times I try it I keep getting 14.5, 14.6 or 14.7 and the letter disappears next to the ohms symbol. The good board, unplugged from the power board reads 33.6 KOhm.

2) 1.5 Ohms bad board.

3) .257 kohms Good board.
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Old 07-12-2019, 09:48 AM   #31
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Default Re: Main board Magnavox 32ME402V/F7

Quote:
Originally Posted by beuknowsdiddly View Post
Okay I'm sorry.

1) No matter how many times I try it I keep getting 14.5, 14.6 or 14.7 and the letter disappears next to the ohms symbol. The good board, unplugged from the power board reads 33.6 KOhm.

2) 1.5 Ohms bad board.

3) .257 kohms Good board.
So C3214 is showing 1.5 Ohms on the bad board, so try removing that C3214 first. But remember this, there are other caps that is connected in parallel with C3214 also, so it does not mean for sure that C3214 is shorted out, it can be other caps that are connected in parallel with C3214 are shorted out, just like in one of the link I provided earlier. So remove C3214 the use the Ohme meter to test the pads on the board where C3214 was to see if the shorts is gone or not, if not, then it will be a lots more work to find out what other caps are connected in parallel with C3214.
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Old 07-12-2019, 04:43 PM   #32
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Default Re: Main board Magnavox 32ME402V/F7

Thanks Bud,

I think it's time to give this board a proper burial. The pads still read 1.5 and since I don't know how to read a board, there's really no point for me to continue. I have no clue where to go next and I'm sure you have a lot more interesting projects and people that DO have a clue that you would rather be working with.

Can you recommend some material for beginners that might give me a better understanding of boards, ohms, resistance etc.. ?

Thanks again, at least I'm a tad more enlightened, thanks to you!
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Old 07-12-2019, 05:33 PM   #33
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Default Re: Main board Magnavox 32ME402V/F7

There are many free online electronics learning sites:
https://www.learnelectronicsonline.com/
http://www.learnabout-electronics.org/
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Old 07-12-2019, 06:36 PM   #34
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Default Re: Main board Magnavox 32ME402V/F7

Thanks again Bud!
I really appreciate all your help!
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Old 07-12-2019, 06:50 PM   #35
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Default Re: Main board Magnavox 32ME402V/F7

Is there a chassis number? (it might be a FL12.3) you might be able to locate a schematic, I believe the fl11.4 is close. You could try using a 9volt battery and connect it across that cap for a couple seconds at a time and see which other component gets hot
If its not a shorted cap it could be a shorted regulator ic input

Last edited by R_J; 07-12-2019 at 07:06 PM..
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