LG TV half of backlight not working

Question

LG Television

Repair guides and support for your LG TV.

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dany613782 @dany613782

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crwdns2931729:0crwdne2931729:0: Ndz 19, 2021

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LG TV half of backlight not working

Hi I have an LG 32LB550B and more than half of the backlight has stopped working, it looks like only the top left LED is working, the rest of the TV still works fine and displays images fine. I’ve looked at the power board and main board and don’t see any burn marks or blown capacitors, although I am a noob to electronics so I’m not too sure what to look for. I’m guessing the problem is probably the LED strips themselves, but I th

ought Id post here if anything else was the problem, I’ve added pictures of the TV backlight.

Any advice or suggestions would be appreciated.

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Hi Dany,

I would double check the LED strip connections, on the power board, but most likely you have a dead LED or a whole LED strip. If I'm not mistaken the TV is lit up by two led strips which are not the worst to replace and it can be done by yourself. Have you got photos of the disassembled power and main boards? Have you taken the screen apart too?

crwdns2934271:0Ndz 23, 2021crwdnd2934271:0 honakrisi crwdne2934271:0

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oldturkey03 @oldturkey03

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crwdns2931729:0crwdne2931729:0: Ndz 25, 2021

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dany613782 this looks like failed LED backlight strips. You will need to replace those. Not a bad job on a panel this size. Of course, you want to measure the voltages on the power board going to the backlight LED are the right voltage. If that voltage varies greatly then the issue would be the power board. This video will definitely be of some help. Post some good images of your boards with your question, that way we can see what you see. Adding images to an existing question

The backlight strips are in the panel so you will have to remove it from your TV and disassemble the panel. Make sure that you mark the diffuser sheets in the proper order and direction. It saves you a boatload of problems later on.

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thanks for your reply ive added in more pictures of the main board and power board they both look fine and I cant see any burn marks, so im guessing its probably the LED's. I would measure the voltages but im a total noob to electronics and not sure where to start.

crwdns2934271:0Nhl 14, 2021crwdnd2934271:0 dany613782 crwdne2934271:0

dany613782 sounds good. I just did a 32" panel today (Samsung TV) and it is not terribly difficult. Takes about 2 hours (leisurely) to replace those strips.

crwdns2934271:0Nhl 14, 2021crwdnd2934271:0 oldturkey03 crwdne2934271:0

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Hi Dany,

I would double check the LED strip connections, on the power board, but most likely you have a dead LED or a whole LED strip. If I'm not mistaken the TV is lit up by two led strips which are not the worst to replace and it can be done by yourself. Have you got photos of the disassembled power and main boards? Have you taken the screen apart too? — honakrisi
thanks for your reply ive added in more pictures of the main board and power board they both look fine and I cant see any burn marks, so im guessing its probably the LED's. I would measure the voltages but im a total noob to electronics and not sure where to start. — dany613782
dany613782 sounds good. I just did a 32" panel today (Samsung TV) and it is not terribly difficult. Takes about 2 hours (leisurely) to replace those strips. — oldturkey03

Mark Self @markself crwdns2934065:0crwdne2934065:0: 1 · Answer 1 · 2025-10-27T17:56:02-07:00

Mark Self @markself

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crwdns2931729:0crwdne2931729:0: tiawara ta 20 agoNhl 27, 2025

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I have an LG 86 inch TV, half of the back light strips aren’t working however they do flash every few seconds, I have replaced the t con board in the middle of the unit with no change.

The left side is bright the right side is dark although a picture is present, I’m not sure what the next move would be

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@markself sounds like a failed backlight strip. It's a beast at 86" You will need some extra room and people helping you to disassemble it right down to the panel. Start off by removing the back panel and let's look at the power board where the backlight LCD's connect to. If you post some pictures of all of the boards etc. we can help you by pointing out where to measure and what to check. This would be just to confirm the diagnosis based on your statement "dark although a picture is present" the backlight strips are the prime suspect. We will need to know the exact model number for your TV. I know it's to late to tell you that it's never the T-con board with the symptoms your TV has :-)

Adding images to an existing question

crwdns2934271:0tiawara ta 17 agoNhl 27, 2025crwdnd2934271:0 oldturkey03 crwdne2934271:0

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LG Television

LG TV half of backlight not working

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