Plasma TV Fix- Sound but No Picture

[dirtyfarmer]

ScratchStart, I need to go and take those pictures you requested.

[dirtyfarmer]

Here are close-ups of the caps that, to me, don't look "perfectly" flat. What do you think?

[DaveO]

I've heard that bad capacitors is a fairly common problem with LCD screens- the guy I was talking to had fixed a number of LCD computer monitors. He got them free because they'd stopped working, replaced capacitors, and in 4 out of 5 monitors he fixed the problem. Seems like it might take some doing to de-solder and remove the capacitors, and carefully note the little holes on the PC board that they came out of, but it may well do the trick.

[Jason]

Those really do not look too bad to me in the pics. Here is a pic borrowed from google.


Notice the three with bubbled up tops.

EDIT: Another good pic

[ScratchStart]

ya, I only see one that is even suspect, the picture with the 2 caps and transformer, the one on the right... The pic of the green colored caps, is that from the same board your power cord plugs into... they are the ones I would think would be causing the problem, and they all look great.

do you have a way to hook them all up and power the tv up?

if you can, take a hair dryer and warm up that cap, with the power on and see if you get sound.

I'm thinking it is probably a feedback power problem. What model of TV is it?

just curious, have you tried to see if you get sound from your audio out RCA's? I believe they pull audio before it goes through all the preamps and speakers on the TV

[DaveO]

I had to read up on the hair dryer trick- one site suggested alternating heat and cold. Anyone know how many times that will work, or is it a troubleshooting technique only?

[sportbike]

ya, I only see one that is even suspect, the picture with the 2 caps and transformer, the one on the right... The pic of the green colored caps, is that from the same board your power cord plugs into... they are the ones I would think would be causing the problem, and they all look great.

do you have a way to hook them all up and power the tv up?

if you can, take a hair dryer and warm up that cap, with the power on and see if you get sound.

I'm thinking it is probably a feedback power problem. What model of TV is it?

just curious, have you tried to see if you get sound from your audio out RCA's? I believe they pull audio before it goes through all the preamps and speakers on the TV

Seems that he has sound, Does not have a picture. "sound but no picture"

[ScratchStart]

HOLY CRAP! you're right....
I have been reading this wrong the whole time.

that changes things.

are the backlights coming on? you should see a "glow around the edge of the screen when you turn the set on.

I have also heard that you can (in a dark room) shine a flashlight through the screen on an angle and you can see the picture. I have never tried this.


as for the hair dryer trick, if it works, you got bad caps.... so unless you want to watch tv and listen to a hair dryer all the time, you'll have to change them.

[dirtyfarmer]

It's a Plasma, not LCD. Samsung P42A450P. I'll have to try your suggestion. I have a heavy-duty heat gun. If it doesn't respond I'll just burn it down then use it for target practice. Definitely landfill fodder then.

[ScratchStart]

ok, on a plasma that trick won't work. the only thing I think it can be is your plasma screen driver board. I may be wrong, but I don't think Samsung sells them seperate from the screen. what 2 boards did the repair man want to replace?