EEVblog Electronics Community Forum
Electronics => Repair => Topic started by: Quantumplate on January 28, 2022, 03:56:42 pm
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It's an LG26LC55 that's been on the blink for some time ie years! Used to get the screen pic attached for about ten minutes, then slowly the working picture would arrive via three horizontal bands that would each start working in turn. After some months though the pic would never arrive. Had some luck replacing a few out of spec caps in the power supply section - there was still a long wait, but the picture would eventually work fine. Now, no pic, just the screen with frozen vertical lines. I've replaced all the caps now bar the two 450v ones on the board. I've also tried two different AV boards - used from ebay, so heaven knows if they were ok to start with, and no change.
If anyone can diagnose from this brief description then I'm all ears and very grateful. Should I replace the final two caps on the power board (the 450v ones)? New to this game.
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If it is obviously a thermal behaviour, get a hairdryer and cooling spray and start searching for the culprit.
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I would assume trouble on the TCON board or in the panel itself. You've more or less eliminated everything upstream.
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Yes, you're probably right about the tcon. I'm trying to remove it but it's got me stumped at the moment. Can't find anything online, do you know the procedure?
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I've never personally seen this model, it isn't in plain view after removing the back?
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That's it under a steel cage. Four screws go thru that holding the pcb down, but if I then angle the cage up and try and pull the board out there 's a ribbon cable holding it back, and doubtful if I have room to pull it out anyway.
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Similar issue to yours?
https://www.badcaps.net/forum/showthread.php?t=23733 (https://www.badcaps.net/forum/showthread.php?t=23733)
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Thanks for the link, interesting.
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Honestly I'm not knowledgeable on this but read
https://electronicshelponline.blogspot.com/2013/06/how-to-diagnose-failed-tcon-board-how.html
if know what it means by video process circuit is than it'd be very helpfful