Samsung Plasma PN50A400C2DXZA

[tom66]

Re: Samsung Plasma PN50A400C2DXZA

It is actually quite common for those MLCC to short, but that is the first time I have seen it on a plasma.

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

So with zero knowledge about this TV, this buffer board receives power through the YSUS through that connector next to the fuse that seems to be blown. I'm guessing the MLCC is the guy that seems to be blackened. What should I do now?

[tom66]

Re: Samsung Plasma PN50A400C2DXZA

Replace that capacitor.

Choose the highest value that you can get in 0603 form factor, X5R, with minimum 80V operating voltage.

The Y-sus connection only acts to limit the wiring clutter. The Y-sus does -nothing- with the Va voltage which goes to the C/X board, it only acts as a connecting point. A failing Y-sus cannot cause damage to the C/X board.

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

What about the blackened MLCC thing? I assume that needs replacing?

[LDSisHere]

Re: Samsung Plasma PN50A400C2DXZA

What about the blackened MLCC thing? I assume that needs replacing?

That is the capacitor that Tom66 is referring to in his post. Something like the two examples below.

http://www.digikey.com/product-detai...3-1-ND/3476112
http://www.digikey.com/product-detai...1-1-ND/2116336

If you have not done much soldering you will need to find some kind of junk board to practice on before attempting to make this repair. You will also want to order a few extra of what you are trying to replace in case they go flying or are damaged during installation.

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

Safe to assume that if my DMM isn't beeping when I test the fuse on that board, that it needs replacing then too?

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

Also, what other tests can I do to delimit the point of failure to just that capacitor and fuse?

[tom66]

Re: Samsung Plasma PN50A400C2DXZA

The location of that capacitor ensures that its failure would have only possibly damaged the input fuse, as well as the 1 ohm resistor next to it (2512 size, probably.) It will have likely failed due to mechanical flexing (movement, dropped in shipping, bumped in production.) Very common on LCD monitors.

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

The location of that capacitor ensures that its failure would have only possibly damaged the input fuse, as well as the 1 ohm resistor next to it (2512 size, probably.) It will have likely failed due to mechanical flexing (movement, dropped in shipping, bumped in production.) Very common on LCD monitors.

Good news then!(?) As far as the other boards, based on the information I have provided, they seem to be working correctly? Obviously I know its difficult to be completely sure, I know its difficult to communicate this all through the Internet sometimes, but I suppose this is the best place to start. I assume that if this buffer board was not functioning then I would not have a picture (but still have the primed panel, soft buzzing from the YSUS and XMAIN, as well as a flashing LED on the control board). Thanks again!

[tom66]

Re: Samsung Plasma PN50A400C2DXZA

Yes. So, replace the fuse, the resistor, and the capacitor, and it should work .

[tibimakai]

Re: Samsung Plasma PN50A400C2DXZA

Sorry about using this thread for a different question, but it's the same TV, but a different issue and I didn't want to start a new thread for just a quick question.
The issue is this:
" has two thick vertical lines on screen"
This issue is with some buffer boards(bottom of TV)? I don't have experience with plasmas.
Thank you in advance for helping me.

[stephenhartley]

Re: Samsung Plasma PN50A400C2DXZA

Yes. So, replace the fuse, the resistor, and the capacitor, and it should work .

Fantastic. However, I think I'm missing one thing, I'm replacing the mlcc capacitor C2523, and the fuse F2500 next to the YSUS. What is the resistor you are referring to? Thanks again!

[powerpipe2003]

Re: Samsung Plasma PN50A400C2DXZA

I have the same problem with the same buffer board but in a Sanyo TV. I am trying to replace the capacitor I cant seem to find that place listed in the TV schematics of the service manual so I'm going to take the examples you listed and get a few to try it. Just curious though, the examples you gave, how do you know what rating capacitors to use?