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Repair guides and support for your LG TV.

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LG LED TV has backlight but no picture.

I have LG 55LA6205. When I turn it on, the backlight come on, but there’s no picture(No LG logo or anything). I checked the voltage on the Power supply, everything was normal. Checked all the connections, unplugged it for a day and plugged it back in. Nothing worked. Until I remember Sometimes I use the LG remote app on my iPhone. It has a feature to view what’s on the TV, like a second screen. So, I turn on the tv, and took a screenshot. It showed the LG no signal cube thing. So I took another one, this time I pressed the input button on the side. It showed the inputs screen. I researched before posting and couldn’t find a definite answer about this problem. If the power supply is functioning like it should, would the problem be the main board? But the main board seems to work. Or could it be the panel. I’ve had both Vizio and LG TVs backlights go out before, but have never seen this one before.

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I have sound but not image; when I point a lamp to the screen I can see some image ... Any suggestion?

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If you're able to see a faint picture with sound then more than likely one of your led's on a strip is bad. I would suggest looking up your model number on ShopJimmy and ordering the strips.

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so my one turns on but its blank black. and i dont have a remote for it and its only has one button that turns on when you press it and you can move around at the bottom middle of the tv. and none of them seem to do anything.

what do i do?

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Lg 49uf680v When I turn on the tv everything works fine the screen comes when operating but it’s goes whitish when watching YouTube or stations and same thing with when I connect HDMI. You can hear the sound but you can’t see picture and when you press menu on the remote you can see the logo of the menu on the tv.

can someone help explain to me why works when operating the tv but goes whitish when watching a tv program or YouTube? Any help

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Hi, does anybody have an update on that topic? I have the same problem since a few days. Last thing I saw where vertical lines and the picture fading away. Now there is just backlight and no UI Elements or Picture.

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I changed out the main board and it fixed it. I’m still using it now

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@seno360 ,

What is the model number of the TV?

Sounds like the backlights aren't working.

Initially try to find the service manual for the TV online. Search for "LG (insert full model number) service manual".

If you find it it will show the backlight power circuit diagrams which will help so that you can test the circuit to locate the problem.

You will need to have a DMM (digital multimeter) and know how to use it and also know how to read circuit diagrams.

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I have the same issue on my lg 50uk6090pua, and after extensive research I found that this issue is typically due to a faulty T-Con board, or a bad led panel. Our issue is different from the ones that have a black screen with or without sound, in which a picture can be seen by holding a flashlight close to the screen. Our sets power one and the backlights as well as the led lights turn on. However, there's no picture, menu, etc. Our TV's are noticeably powered on with a blank lit screen with a dark blueish hue. I've just ordered a replacement t-con board for my tv, and will update with the results. I found one fairly cheap on e-bay, hopefully it works. I'll post my results in a few days once I get the replacement. If it fails, I'll test the voltage on both my current and replacement T-con boards, which if both are bad, I'll order a new one from lg. If they're good, I'll look into replacing the led panel itself. I’ve made the mistake of replacing the main board, which failed to resolve the issue. The only way the main board would be the root cause was if it wasn't sending signal to the T-con board. This can all be checked via voltage meter, which i don't currently have, but will be purchasing soon. Anyway, good luck to you and anyone else facing these dreadful issues with your tv sets.

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Hi have you managed to fix the issue. I have the same issue and looking to do a fix myself. Thanks

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Me too. No ideas yet?

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Hi.

This is could be a bad lcd. It can be a bad video card(maybe a capacitor on the video card). It could be other things too. Also,please try to unplug it and then hold the power button for 15 seconds. That drains all residual power. Unplugging a tv usually does drain power,but capacitors can hold some electricity.

now you say it’s a black screen maybe slightly blue…have you aimed a flash light at the tv and tried to see if you see an lcd image? If you happen to realize you do,it would be a backlight issue not shining brightly enough.

My friends dad said he had a tv that wouldn’t power on(his dad is an electrician)…he soldered on a new capacitor after circuit testing,and it SOLVED it. You can test capacitors.

There are places that specialize in repairing tvs. I know Best Buy geek squad does.

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The backlights come on like normal. I replace backlights before(and there not easy btw). I don’t think that’s the issue. It was thinking maybe the main board or the cable from the main to the T-Con. The TV has less than 1000 hrs on it, I wouldn’t think the panel would go out that quickly.

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It’s very likely a component issue or the video card. Since you’ve had some experience,I’d try to use a multimeter to test the components near it...especially capacitors. You test the resistance by using continuity first. YouTube it if you need to.

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Capacitors seem to be very likely to go bad. Sometimes it’s evident,like maybe being black and burned or oxidized.

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Replacing a part is easier than diagnosing it sadly. I’m only 20 and am just beginning to practice diagnosing components. It’s a pain. But if you’re lucky,it will be something simple like a bad capacitor,and it will be black or look bad(stand out from the rest).

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I don’t think it’s the connector cable. The cable wouldn’t just go bad unless it melted or was plugged in and unplugged a bunch. I truly think it’s a capacitor or video card. Maybe another component. Sometimes power ic chips(usually little square black cups with 4 or more pins in the sides called a mosfet). A power ic chip can go bad and not allow power to the lcd. If any component shorted or burned,it’s usually evident at least somewhat. There is freeze spray on amazon...it’s made for electronics. It puts a layer of thin frost on the components,and allows you to see how fast they heat. I don’t think this is as useful in this case,but if you see an area you suspect,this could help you narrow it down.

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I think you should try the multimeter. The one I’ve started using is the hyper tough one from Walmart for $18. Make sure you don’t get a simple voltage tester for ac.

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Please post back if you need more help. Sorry,again,im newer to component troubleshooting. I could replace stuff when I was 11 like a tv charging port...but I never was advanced until now. I hope I’ve helped a little bit even?.?

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YouTube is your best bet with help on exactly what to test and how.

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IMPORTANT...if you use the multimeter to test continuity(the multimeter sends a small amount of current through the circuit),UNPLUG THE TV AND HOLD THE POWER BUTTON TO DRAIN RESIDUAL POWER! IF YOI TEST THE LIVE VOLTAGE,BE CAREFUL. CAPACITORS CAN BE DANGEROUS,SO MAKE SURE YOU ONLY TOUCH THE PLASTIC HOLDERS,AND DONT SHORT ANTHING.

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Again,good luck. Let me know if you need any other help. I honestly don’t mind trying to help a bit more. I’ll reply tonight if I can.

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@skyethespy i had this same issue. My TV sound works, I can change channels but no picture. It lights up so the led seems to be working. Turned it off for 6 hours and turned it back on and same issue. Change the power, tco and main boards and same issue. Cut the TV off, held the power button down for 30 second waited turned on and same issue. Disconnected the TV held the power button down 30 seconds. Plugged it back up and same issue. My model # 75uk6190pub. The power button has never flashed before it went out. Now the only thing I've noticed that changed is it flashes 3 times then powers own. Sound and functional but still, no picture. No even putting a flashlight to it. Any suggestions?

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lt’s likely to be the LCD panel that's faulty or more specifically the long thin circuit board attached to the LCD panel at the bottom.

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Martin Oliver the OP repaired it by replacing the Main board. It had nothing to do with the LCD driver boards (the long thin circuit board).

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