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LG 47LB5900-UV TV display is flashing / flickering on and off

I have a LG TV 47LB5900-UV, which is about 1.5 years old and the screen suddenly started flickering on an off. I was watching TV on it and suddenly the display just went off, the flashed on then back off. At this point the display is primarily off, but flashes on for half a second, then back off. This is happening with the initial screen, on screen menu, and with any input. I opened the back and reseated the internal cables between the 3 boards, but the issue remains. The connectors on each cable are somewhat recessed, so I am not sure of a good way to clean them.

The TV doesn't seem to be completely powering on and off, just the screen is flashing on/off. Whatever is would normally be displayed is just flashing on briefly until I turn the TV off.

Please advise how to test and further isolate to which component should be replaced.

Tcon? Power board? Main board? Cable?

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I have the same exact problem. Replaced TCON but still the problem remains. Any updates from you? May just call the service tech

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It sounds like a back light or power supply/ LED driver board problem. Look for bulging capacitors on the power supply board. If they all look ok, check connections on the back of the power supply board and the LED driver board if it is not part of the power supply board. Some models combine the two on one board.

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post some images of your boards with your question. that way we can see what you see. Use this guide Adding images to an existing question for that

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i whas heving the same problem i did replace caps on the power sepply after replace the caps my screen whas getting verry hot what can that be

the ratting on the caps whas 10v 3300uf and i have replace that caps with 10v 2200uf can it be the caps of me

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Had same prob lg 50 smart TVs. Take back off to undo all connectors and check for little strands of glue stuck between connectors easy fix never had a problem since. Before was flickering all the time half a picture or coming on with sound onlyand now works great

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Replace all led strips...had same problem...R & R'd all boards ( psb, t-com, and vid board).....same problem. End result...Bad led strip, since they age at similar rate, replace ALL! delicate job....Or part the LG TV out and buy anything but LG....Mine failed 1 month past the warranty....evidently a common LG TV problem (after reviewing LG flicker problem)!!

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As a technician I can tell this is not just a LG problem. It's one of the most common problems I see these days, in all Brands.

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As a technician, what has been the issue that you are seeing in all brands?

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As a non-technician, I've replaced LEDs in LG's the most, but I've done it in Vizio's and Samsungs as well.

Usually a TV non-powering up is the Power board. Look for Bulging Capacitors, although for a Vizio I had. The T-con board went out and that was the easy cheap fix.

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It sounds to me like you have a bad power supply board. Some component on it has gone bad either a cap, resistor, diode, or even a fuse. There are various components on the board that need to be tested. If you are familiar with soldering and desoldering, then go ahead and remove each piece and perform and ohm test as well as resistence test. Check relays as well. Most of the time one or more components on the HOT side of the board go bad. This can be time consuming so I find it easier to simply replace the entire board.

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Lol i had the same or similar symptoms. After a few weeks of freakimg out i was smart tv page with the live preview screen in the top left. And the preview screen blinked showed lines not the whole screen. That immediately made me realize the tv is perfectly fine. Its either my cable or computers graphics card.

So my tip for all you fellas is check to see if the flickering still happens when your in a tv menu or smart home page.

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The backlight inverter board might be broken. check where the backlight plugs in and try replacing that.

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Yep..its board that powers the leds...or leds themself i had 65 inch samsung ended up wiring and sautering the not lit up strips to each working strip ..quick easy fix

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Hi You will find that a few of the leds have blown and taken out the power board , you will need a new PCB and new leds mines had exactly the same problem after two years running, i put it in the bin to save a lot of heartache cause if you get it repaired it will almost certainly happen again unless you can turn the backlights down , incidentally out of all the lcd televisions i have had its only the lg smart tv that has let me down after such a short time

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I had this problem and I found that an LED had caused the problem. Instead of replacing the single bad LED's [there were two] I chose to replace the strips containing the bad ones. I will tell you if you decide to do this job yourself BE CAREFUL with the main screen if you crack it, might as well toss it, it will be cheaper to buy a new one. Hope this helps!

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Where do you get the replacement LED strips?

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ShopJimmy.com carries LED strips. You can also try eBay. Again as Bill above states, be careful removing the LCD screen, because if you damage it, then there is no replacement for the screen yet.

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Was it like this?

https://www.youtube.com/watch?v=2ppAUuvm...

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Hi Vafa

Yes mine is exactly like that. How do I fix it?

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I ordered the LED set and not 100 % sure about it. Next week will find out.

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I tried to find any documents about this stripe's and the actual LED part numbers, didn't find the datasheet and found this : https://www.ebay.com/itm/263807157267 but couldn't find any evidence that's the same LED on strip and didn't bought it(~10 cent per LED!).

Anyway the stripe is two different size, one with 5 and other with 6 LED on it. Part number : 6916L-1988A and 6916L-1987A

I ordered them from shopjimmy(on ebay) due to faster shipping offer that they have and will get it by Wednesday, but If you are not hurry, get it with lower price here: https://www.aliexpress.com/item/-/328945...

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Finaly I fixed my TV with replacing all of the LED's. The new set is not LG and fit perfect.

Only on absolute white screen can see the light gray shadow around all four corners.

This new set also make less heat.

One of the plastic fasteners that hold the LED covers fell and case the shadow and make me to disassemble the unit twice. Use light glue in case those plastic damaged.

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Same issue here, I hope it works for you. Please let us know.

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timnance will be eternally grateful.
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