LG 50PK series display issue

[tobias]

Hi everyone,
When I turn on my 50PK760 LG plasma the bottom part of the sreen has a border (visible right on top of the + on the first picture) that becomes darker a few seconds later (second picture). Then it starts to be distorded (third picture) to become and stay black (last picture). All this sequence takes approximatively 2 minutes.

I am thinking of the bottom Y buffer board but there are no shorts after checking it.

I checked VS: 201V and VA: 59V

Any ideas?
Thanks!

[tobias]

Re: LG 50PK series display issue

Pictures don't seem to work. Here there are direct links:

http://img110.xooimage.com/views/3/b...--47e8db2.jpg/

http://img110.xooimage.com/views/9/a...--47e8db4.jpg/

http://img110.xooimage.com/views/6/c...--47e8dbc.jpg/

http://img110.xooimage.com/views/9/e...--47e8dc7.jpg/

http://img110.xooimage.com/views/8/e...--47e8e09.jpg/

[tw2005]

Re: LG 50PK series display issue

Best way with pictures is to go advanced, manage attachments and upload as thumbnails.

I'd go with bad lower buffer.
I have seen something like that but no where as extreme on a 50PK550 which I'd expect to be the same board after i replaced a board shorted by a cockroach.

Not greatly noticeable but the lower half did have a slightly dimmer display. Your first shot reminds me of that but yours is much worse.

Sounds heat affects the fault

[tom66]

Re: LG 50PK series display issue

I agree, bad lower buffer

[tobias]

Re: LG 50PK series display issue

Best way with pictures is to go advanced, manage attachments and upload as thumbnails.

I'd go with bad lower buffer.
I have seen something like that but no where as extreme on a 50PK550 which I'd expect to be the same board after i replaced a board shorted by a cockroach.

Not greatly noticeable but the lower half did have a slightly dimmer display. Your first shot reminds me of that but yours is much worse.

Sounds heat affects the fault

Thanks for your prompt replies. I'm leaning toward lower buffer also but there are no shorts and by touching the heatsinks no one is hot compared to the upper buffer board.
Also, control board led is blinking once normally then right after flashes once and so on.

[tom66]

Re: LG 50PK series display issue

Try using a household hair dryer to heat up the upper & lower buffers - see if the fault occurs quicker then.

[tw2005]

Re: LG 50PK series display issue

The bottom buffer is only$20 and ysus $40 at SJ, very cheap compared to most plasma Tv parts. Could replace the lot at $80

[tobias]

Re: LG 50PK series display issue

Just an update for those who might have the same issue in the future. It was indeed a faulty lower buffer. Works like a charm now.

Thanks to tw2005 and tom66 for their help.