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

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Didn't find any bulging capacitors . I will check the back of the power supply board later today. Also will take better pics. Thanks for the advice so far

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Any updates... Im having same problem with the same tv model.? No idea with the problem

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Bad LED strip. Trying to track down replacement strips to change out all. If anyone finds some please shoot a link my way. This will be a little side project

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Can anyone help my tv has started flashing on An off? I've had it about 2 years now !

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My LG tv is doing the same ! The tv doesn’t turn of just the picture blinking on and off, has anyone actually found the problem and sorted it??

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I have an LG 47LN5750 with the same issue. I have 3 rows of LEDS working and 3 not. I swapped all the strips around and they all work, so 3 rows are not getting power. I swapped out the power board with a known good one and the same 3 rows are still out. The only things left are the 4 wire cable from the power board to the LED board that runs down the side of the unit and all of the LED strips plug into it. What are the chances that either of them is the problem and where can I get that board, I have not seen one anywhere online

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hi have just stripped down my LG 47 LB630V found 4 strips of leds ,each of the 4 strips are split in to two strips of 4 and 5 leds which plug together to make 9 per strip , the top two strips and the bottom two strips are fed from two different supplies to split the load ,the voltage on mine is showing one output of 35 volts on one strip and 63 volts on the other , the top two strips with 63 volts is flashing and the bottom two rows with 35 volts will not light up at all,when i swapped the led supplies around the bottom row would flash ,there was one or two leds out on a couple of the strips ,this tells me that the power pcb is goosed ,and that all the led strips need renewed when you add up the cost and the time to repair it is it worth the effort ,I'm getting a new one and turning the backlights down to prolong the life of it .ps mines was only two years old

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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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