LG Plasma TV has no picture

[CHRISS]

Hi Blind Freddy
As mickstv say the plastic loom is a common mistake that is made when fitting them we have all had problems when 1st confronted with them now we no to be extra careful with them and make shore they fit all the way in and no contaminants on the contacts just clean them up if tarnished or dirty
glad its working now

chriss

[Blind Freddy]

I too am glad it is now working.

Thanks to all that helped with this project ..

Now to work on an old high power Arlec charger, getting the IC will be the trick here..

Regards Freddy..

[Bibliophile]

Hi BF
If you post any numbers / letters / markings on the IC we may be able to help.

[nvrfdaway]

Hi Guys,

Sorry to revive an old thread. I was looking for information to fix my tv and find this site to be very informative. If anyone could give some advice it would be greatly appreciated.

I have an LG 50PG10, same issue as OP. I suspected the lower Y buffer board was broken, followed the advice and took each board out at the same time. When I removed the lower board I got the top half of the screen turn on, however, it had lots of static. I then tried to move the upper board further into the ysus as it was quite loose. The picture improved for a second and then went black. I tried moving the upper y board in and out a little hoping to get the picture back on but it didn't work.

I know I need to replace the lower y board. Did I fry the upper board too when I touched it? I sensed a little current in my hand until I realized my mistake. When replacing the buffer boards, how do you remove the connectors to the screen? I flipped the metal clasps holding the tape connectors, but they still wouldn't budge when I pulled on them. My knowledge is lacking, but I'm pretty sure I can get this done if it's just a posts swap. A shop told me the original problem, but were vague.

Thanks for any help I can get!

[Tom Mix]

Any shrinks on forum to give help? Sounds like ham- fisted bodger! Sounds like left power on while moving closer? to y-suss?etc! This is the prob with open forums where highly tech probs are misunderstood by beginners- & it don't help the few remaining members of a dissappearing tv repair trade! Where idiots bugger up their set then expect a repairman to fix it for nothing of course!

[CHRISS]

Hi Guys,

Sorry to revive an old thread. I was looking for information to fix my tv and find this site to be very informative. If anyone could give some advice it would be greatly appreciated.

I have an LG 50PG10, same issue as OP. I suspected the lower Y buffer board was broken, followed the advice and took each board out at the same time. When I removed the lower board I got the top half of the screen turn on, however, it had lots of static. I then tried to move the upper board further into the ysus as it was quite loose. The picture improved for a second and then went black. I tried moving the upper y board in and out a little hoping to get the picture back on but it didn't work.

I know I need to replace the lower y board. Did I fry the upper board too when I touched it? I sensed a little current in my hand until I realized my mistake. When replacing the buffer boards, how do you remove the connectors to the screen? I flipped the metal clasps holding the tape connectors, but they still wouldn't budge when I pulled on them. My knowledge is lacking, but I'm pretty sure I can get this done if it's just a posts swap. A shop told me the original problem, but were vague.

Thanks for any help I can get!

If set was on when disconnect upper you may have damaged it allso the y pcb and lucky not yourself as well,
the flat ribbon connecters are hard to take of the 1st time have to lift the flat lead till tabs at side are free and gently pull out

Chriss

[nvrfdaway]

Thank you kindly Chriss, much appreciated. I will go ahead and replace both y buffers, hopefully the ysus isn't fried as well.

Let my amateurish mistake be a warning for the rest of the casual forum browsers! I may be wise to call in a few favours from friends to make sure I don't mess it up any more. I'll update once I manage to fix the tv because I don't give up easily (even though I should sometimes).

[Peter_G]

Hi all,

I know this is an old thread but hoping to get some help.

I have a LG 50PG20D with the same issue as the OP. This appears to happen every three years. The first time it was under warranty (after 3 years, thank god for extended warranty) and the Tech guy replaced a board in the back.

Now three years later it's happened again and is out of warranty but I'm happy to replace the faulty board myself but just wanted to clarify the process. So if I understand correctly I take one of the two boards out at a time (with the power off of course) then power on and see if a picture comes up. The one that gives no picture would then be the faulty board. Is that correct?

Thanks in advance.

[Peter_G]

No-one able to help?

[mickstv]

Forget about the O/P.

Can you tell us exactly what your symptoms are please.

[Peter_G]

Hi Mick, same as the opening post on page 1, TV has lost picture (black screen) but still have sound. It appears to be a common issue with LG plasmas.

It's happened once before 3 years ago but was under warranty so LG came out and replaced a board.

[mickstv]

Hi Peter, on it's last repair did you get a job report stating which board was replaced ?

[Peter_G]

Unfortunately no I didn't hear anything more after the repair.

[Peter_G]

If I remember correctly it was in the top left hand corner vicinity (looking from the rear) if that helps at all.

[mickstv]

Faults generally revolve around four boards, the Ysus, Zsus and upper/lower buffer boards. The Ysus and Zsus boards have fuses on them that can be checked.


A word of warning, if you haven't got any electronics skills, find a TV tech and get a quote.

[mickstv]

If I remember correctly it was in the top left hand corner vicinity (looking from the rear) if that helps at all.

Missed this post.


If it is the upper buffer board, it can be tested by removal. Once removed if the picture returns to the bottom half of the screen, the top board is faulty.

To remove, disconnect from mains. disconnect wire loom between the upper and lower buffer board, then unplug buffer board from the ysus board.


Warning lots of high voltage, work on it at your own risk.

[Peter_G]

Ok I'll give that a go. I have basic electronic skills and build PC's so hopefully should be fine.

Thanks for your help so far Mick, much appreciated mate.

I'll report back later.

[Peter_G]

Hi all,

Finally after 1.5 years I got motivated enough to try this yesterday. I removed the top board and no picture. I went to put it back on but the card backing on the top ribbon cable came off. Made it extremely hard to put back in without it. I got it in and removed the bottom board and got top of picture back. Only thing is I think I have damaged the top ribbon cable trying to plug it in. I now have lines on the top third of the top half of picture.

Here are links to some photos I took of it.






So what I need to know now is this ribbon cable replaceable or is it like that because the bottom board is out? Or is the tv now stuffed?

Peter

[TVguy]

.. Or is the tv now stuffed?

Well and truly stuffed!

The FFCs are bonded to the panel; break the cable, break the panel.

EDIT: If you can, try to replace the FFC backing stiffener it may help, as it is conceivable that all the terminals are not making a secure connection. If you can see any physical damage to the cable, then it is stuffed.

[Peter_G]

I'll put a little glue on the stiffener and try that but otherwise I too think it's stuffed now. Not to worry, I was just going to put it in the spare room. If putting the stiffener back on helps I'll let you know. Thanks TVguy

edit: There is no damage to the cable from what I can see but don't have glue in the house to put the stiffener back on. I'll grab some tomorrow and give it a try.