Troubleshooting Intermittent Screen Flicker on Samsung LN55C630K1F LCD TV

[yungman]

I have a Samsung 55" LCD TV that is over the warranty. The model is LN55C630K1F and version is SQ01.

The screen start flashing like the screen get darker and flash quite bright at like 4Hz intermittently. At first I can change channel or change screen display and it will stop. But is slowly getting worst.

I had gone online and look for the service manual with no luck. I need to find the schematic so I can get into it. Anyone has ideas where can I find the schematic or have any opinion on what's the problem. I don't exactly want to open it blindly and probe and I am too cheap to call for service yet because being in field service before, the hardest problem to find is intermittent, I still cannot control how to get it flash at will.

Thanks

Alan

 

[vk6kro]

Most TVs have an automatic brightness control so the TV's brightness depends on the room brightness.
This might fail in a way that results in strange pulsing of the screen brightness if an electolytic capacitor was to go open circuit, for example.

If this seems a likely source of the problem, you might be able to disable this feature in a menu and see if that makes any difference.

Just guessing, of course.

 

[yungman]

Thanks, I'll look for the auto brightness.

 

[MATLABdude]

If it's slowly degrading, it could be the capacitors on the power supply / logic board. Samsung (or whoever supplies the power supply boards) seems to cheap out on capacitors (12th post):
https://www.physicsforums.com/showthread.php?t=515029

This forum might help you with the disassembly of your TV (or let you know how many others are having troubles with the same model):
http://www.badcaps.net/forum/showthread.php?t=11439

 

[yungman]

If it's slowly degrading, it could be the capacitors on the power supply / logic board. Samsung (or whoever supplies the power supply boards) seems to cheap out on capacitors (12th post):
https://www.physicsforums.com/showthread.php?t=515029

This forum might help you with the disassembly of your TV (or let you know how many others are having troubles with the same model):
http://www.badcaps.net/forum/showthread.php?t=11439

Thanks, I did not see this post until now. I'll check into this.

 

[likephysics]

I have a Samsung 55" LCD TV that is over the warranty. The model is LN55C630K1F and version is SQ01.

The screen start flashing like the screen get darker and flash quite bright at like 4Hz intermittently. At first I can change channel or change screen display and it will stop. But is slowly getting worst.

I had gone online and look for the service manual with no luck. I need to find the schematic so I can get into it. Anyone has ideas where can I find the schematic or have any opinion on what's the problem. I don't exactly want to open it blindly and probe and I am too cheap to call for service yet because being in field service before, the hardest problem to find is intermittent, I still cannot control how to get it flash at will.

Thanks

Alan

Is it something like this - http://www.youtube.com/watch?v=W5jH5Mb9zU0&feature=related

My compaq laptop has horrible intermittent screen flicker problems. It's supposed to be a loose connector.

Maybe it's just the back light or the back light power supply. Just a wild guess.

 

[jim hardy]

here's a link to a forum for people struggling with same troubles..

really not very technical , but maybe you'll find somebody who's had success with your model tv there.

http://www.ecoustics.com/electronics/forum/home-video/700527.html

I was able to download a manual for Daughter's TV from Vizio but it didnt go into the boards or how they communicate, just wiring diagrams. Maybe Samsung will be more user friendly.

About halfway down this link is interesting post, two folks report fixingg theirs..
http://forums.cnet.com/7723-13973_1...lickering-problem-so-dissapointed-in-samsung/

Samsung 55" LCD TV Model LN55C630K1F Screen Flicker Easy Fix


by TFurm - 1/29/12 2:03 PM

In Reply to: power supple by notsohappywithsamsung


Samsung 55" LCD TV Model LN55C630K1F screen flickering problem SOLVED ! The problem is not the power supply in all cases. There is a little jumper wire about 3/8 inches long that you can cut and the screen flickering goes away. It is labeled JP854 on the power supply board. Take off the back panel of the TV (Model LN55C630K1F ONLY! I don't know about other models). The power supply board is the brown one that has a big 55" on the upper left hand corner of the board. JP854 is directly down and to the right of that numer 55. It is a vertical wire. Using a pair of angled wire cutters, clip this wire at the top and bottom. Install the back panel, and reconnect the wires to the back of your TV. Enjoy...no nasty Samsung repair men to deal with. IF THAT does not work, your power supply was bad to begin with. Replace the power supply board (Part Number BN44-OO342B; about a 10-15 minute fix depending on your technical experience) and your TV is as good as new. Hope this helps everyone who has a problem, I know it worked for me. If you need pictures, feel free to e-mail a request

 

[yungman]

Is it something like this - http://www.youtube.com/watch?v=W5jH5Mb9zU0&feature=related

My compaq laptop has horrible intermittent screen flicker problems. It's supposed to be a loose connector.

Maybe it's just the back light or the back light power supply. Just a wild guess.

It is not exactly like the video. Mine flash much faster but the picture does not darken all the way down, it just go brighter and dimmer. I am going to try unplug the tv and see what happen.