LG 50LN5100E Video Problem

[jstiene]

Hello. I have a LG 50LN5100e with a video issue. when powered on, I will get about 5-6 horizontal lines across the top of the display and will then disappear. Backlight works fine.

I tried to replace the TCON board with same part number, same problem. I then took the exact same physical TCON board but with a different part number, installed it. I was able to get video but with snow or distortion. I tried 2 other compatible boards all with the same results of horizontal lines. But the one board that is not compatible display video.

It this a bad panel or a different problem? All 4 TCON boards are identical looking except the part number. What would cause one of them to display video, but distorted?

Any help would be appreciated as I am trying to determine if the panel is bad.

Thanks!
Joe

[tvtimmy]

Re: LG 50LN5100E Video Problem

Try a mainboard re-flow.

[jjanssen7]

Re: LG 50LN5100E Video Problem

See this thread:

https://www.badcaps.net/forum/showthread.php?t=59362

You might find some things to try there. I think it maybe a very similar model.

[Nick's Tvs]

Re: LG 50LN5100E Video Problem

With your original T-con board, disconnect the left ribbon between the T-con and the panel and leave the right ribbon plugged in. Are you still seeing the lines across the screen? If no then bad panel. If yes then repeat with the other side. If lines still there then you could have a bad main or bad T-con. If you are able to get ride of the lines by disconnecting half the panel then the half disconnected is causing the issue.

Also if you are able to pull up the menu and the lines appear behind the menu, then we have bad main board.

[ReeceyBurger123]

Re: LG 50LN5100E Video Problem

Panel failure.

[jstiene]

Re: LG 50LN5100E Video Problem

So I ordered a 2nd TCON board and installed it last night and now I get this type of video. Previously I had a few horizontal lines and now I get full video but distorted. This TCON is noted as a replacement part number from the original TCON that was installed. Any suggestions what is causing this?

Thanks in advance!

[dick_barton]

Re: LG 50LN5100E Video Problem

Looks like the wrong panel selected in the Service Menu but there still appears to be lines across the top of the screen.

[jstiene]

Re: LG 50LN5100E Video Problem

I didn't change anything in the Service Menu to select the panel. Would you be able to tell me how to change that?

[dick_barton]

Re: LG 50LN5100E Video Problem

I wouldn't bother to change anything unless you are convinced that the lines are not there. They look as though they still are in your picture above.

[jjanssen7]

Re: LG 50LN5100E Video Problem

jstiene, Did you try reading through that link above? That person was able to work-around the lines by determining what side of the panel was causing the lines. Do the lines "twich" at a regular interval? Do they appear and disappear in a predictable pattern? Common problem with those LG LCD's and there is only one workaround in that case.

[jstiene]

Re: LG 50LN5100E Video Problem

jjanssen7, the original problem was about 5-6 horizontal lines across the screen for about 2 seconds when I turned the TV on. They would disappear after a couple seconds and I would then just have a blank screen (white backlight on)..as if the tcon shut down...with the replacement, I now get a screen image, but distorted...

Thanks
joe

[jjanssen7]

Re: LG 50LN5100E Video Problem

Did you try (with the original tconn) trying to connect one side of the tconn ribbons at a time?

[ReeceyBurger123]

Re: LG 50LN5100E Video Problem

Panel failure.

[vinceroger69]

Re: LG 50LN5100E Video Problem

certainly looks like panel failure.

[jstiene]

Re: LG 50LN5100E Video Problem

jjanssen7,

I did first try to disconnect each of the TCon cables one at a time. The result in both cases was a white screen on one side and a blank screen on the other side...

is it possible panel is bad as others are suggesting?

[jjanssen7]

Re: LG 50LN5100E Video Problem

Yes, it looks that way. In my experience if you can figure out if there is one side that displays normally than you can try the tape trick. Does your TV still display a picture for the first few moments (although with lines) as it did originally? You have to get it back to that point first.

[jstiene]

Re: LG 50LN5100E Video Problem

jjanssen7,

originally, when I turned the TV on, I never got video. Just 5-6 horizontal lines across the screen that only lasted about 2 seconds. No video at all. the lines would only be there for about 2 seconds and then fade away. I would then be left with a blank screen. Never any video at all displayed. Then I tried a replacement TCON (Same part number), with same results. I then tried 2 different TCON board with different part numbers but compatible replacements (per Shopjimmy). With these 2 compatible boards installed, I did get video with each board, but distorted (albeit slightly different with each board). That is what makes this so odd...If I remove one cable between TCON board and panel, I get white screen on one half and blank screen on the other side. Again, never any video.

Lastly,...just to try and explain as best as I can...the original TCON board and its replacement never displayed video...the other 2 TCON boards BOTH displayed video (2 different part numbers).

All 4 TCON boards physically do look alike..just different part numbers...probably different timing and firmware I assume...

[jjanssen7]

Re: LG 50LN5100E Video Problem

The first part of your reply was all I needed to hear. lines but no video. Having heard about your testing, It does sound like panel fault.

What interests me is that other tconns give you video, albeit distorted. That's curious to to me, but somebody brighter than I would have to explain now that could be the case.

Just for giggles, what is the number printed on your LCD connector boards?