LG SmartTV [LG42LN570V] Red stand by light blinks 3 times!

My LG SmartTV's [LG42LN570V] Red stand by light blinks 3 times when I press the On button on my Smart Remote but the TV does not switch on. The stand by light then goes out. Anyone know what's happening?

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Sounds like hardware.

Try the usual of unplugging all HDMI and power cables, waiting a few minutes then just the power cable then re-test. If it fails get repair estimates.

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Here's LG Support

UK Support Good afternoon you're through to Ben at LG Customer Support. How can I help you today
Me: HI Ben, my LG SmartTV [LG42LN570V] Red stand by light blinks 3 times and then goes out. The TV does not turn on. What's happening?
UK Support How strange.
UK Support Have you tried unplugging the TV for a minimum of 6 hours?
Me: You're joking!?
UK Support This resets the power module in the TV and flushes out any remaining power that could be built up in the device.
Me: Will that take up to 6 hours?
UK Support It can take around 4, however we usually advise up to 6, just to be safe.
Me: Why has this happened?
UK Support It could be due to static buildup in the TV, how old is the TV?
Me: bought 23/11/2013
UK Support Okay, so it seems likely it could be static build up. Is the plug directly in the wall or in an extension lead?
Me: Extension lead and don't worry it's good.
UK Support Have you solved the issue?
Me: No I'm saying the extension lead is A OKAY.
UK Support Okay, can you please try plugging the TV directly into the wall once you have unplugged it for 6 hours, as this would confirm that nothing else would be influencing this, and would confirm if the TV was at fault.
Me: OK. What do I do if it still does not work?
Me: Still there?
UK Support I am still here. If that doesn't work, then the TV would need a repair.
Me: Ok I'll try that. Have you heard of this before?
UK Support Only once personally. Unplugging it resolved the issue, so I hope this works for you.
Me: Ok Tanks!!
UK Support No worries at all Eamonn, enjoy the rest of your evening.
Me: With no TV!! Bye.
The operator has ended the chat. Thank you for contacting us!.

This was LG Chat a short time ago.

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Time to try that.

I've yet to find a 6 hour wait help but hey, worth the try.

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Did it work, I have a pretty new lg 4k ultra HD and it just went black, standby flashes 3 times that's it

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Why ask here?

It's faster to try it yourself. But I think it doesn't help.

Anyway, if "pretty new" means it's still in warranty, it's not your problem.

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This happened to me as well. Bought an LG 4k tv 11/25/16 and it "broke" 11/26/16. Just turned off, then turns back on, then does the 3 flashes

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(NT) mine went black the same day too! 12/7/16
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Having this same issue w my new 4K LG. Did this get resolved?

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My Advice?

Buy a new one. While a few people might have solved the problem with new LED lights, which requires total disassembly, I replaced them, tried a new Power Board, sent it back. Tried a new Main Board, and sent them back. Spent $160 on parts and $56 on tools, and a bit of postage too.

TCL has some nice, cheaper 4K models for just a little more than that, and my television is still sitting in my living room, not working, and taunting me.

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Led flashes 3 times and dies

Here is a heads up. If you order any parts for the TV you have to use the SVC code which is the model number of the TV plus a 7 character Alphanumeric code. That Alphanumeric code has to match or a replacement board will not fix it. My TV is an 47lm6700 and I had a constant welcome screen. Taking the main board out and placing it on a piece of cardboard in a 385 degree oven for 10 minutes and letting it cool for 20 minutes fixed it. Basically it's just wave soldering it because troubles are caused by a cold solder on one component. The TV worked fine after my fix but I ordered a new main board and then the TV had the power LED blink 3 times with the replacement that was the same model number. LG has zero documentation about matching the Alphanumeric code on all components. Even their web site lists replacement cards with different model numbers but no mention about also having to match Alphanumeric codes. If your TV is dead I would try the
'heating the main board" trick because it costs nothing. There is several videos on youtube showing how to do it.

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Matching the sticker on the CB not a Biggie

Since no boards are really new what you have to worry about is whether the board you're buying is broken in the same way. I'm not sure how much you've read about these, but I've been reading and working on mine since November when it burnt out. They all have almost exactly the same defect. On mine, the sound continued but the picture went out. All of the unplugging, plugging back in is useless.

I'm pretty sure my screen and side-boards are good (inverter boards?). I'm fairly sure it was the power board.

I tried baking it--did it twice, just in case. That didn't work either.

I found this small burnt looking spot on the back of the power board, and these weird hoary-hairs (perhaps dust?) that were on the legs of components on the other side. But I bought a replacement board from "Encompass" and it didn't work either. They're supposedly the certified parts people. But the truth is you're not getting new parts, just refurbished ones.

Again, the best advice is to just move on. Don't sink a lot of money into this sinking ship. A new TCL 55" is $298. I wish I had. Don't buy LG, although ironically I'm still watching a 42" LG. This might have just been a lemon. I'd stay away from Westinghouse too.

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The model noted at the top post shipped in 2013.

That's 6 years so any new failures are now past the usual 5 year design life. Yes, you read that right. It looks like these are designed for about 5 years of life. Smart phones design life are less to about 2 years on some models.

And yes, some get more or less years which is how life span works.

The issue here is that if you research ALL MAKERS you find the same story about failures and the CTR (cost to repair) can be too high to justify repair.

Here the minimum shop charge is 150USD and 60USD for the transportation to and from the shop.

Those TCLs and SCEPTRE TVs certainly look enticing now.

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Mine bought in 2016/November

it lasted 25.5 months. I rode it hard.

It was a 50" UH5530-UB 4K model.

A particularly large number of these fried, some right away, and others in the first two years. I had mine plugged into a brick the whole time so that might have made it last a bit longer. I'd suggest anyone get one of those.

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That's pretty short.

Also, I keep reading folk don't know how to troubleshoot such things. Remember I ran repair shops so we had no problem getting service manuals and swapping boards. notes the would be repair person didn't know how to test the LED strips. I don't want to upset anyone but that test is now on the interwebs. My test is too simple. Unplug the strips and see if the set comes up. No test gear required for that one.

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Did you resolved?

What was the problem?

Thank you very much

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Brand new LG red light flashes 3 times then goes off

I just bought a LG 55UHD61. When I try to turn it on, the red light will go on, but the screen will remain black. When I push ANY button, the red light flashes 3 times and then goes off. I tried with unplugging the TV for 6 hours and then plugging it back again, still nothing. What a piece of crap

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I had the same problem after a lightning. Changed the main board(cost was £45) and solved it.

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It needs repair work done

More than likely the main power supply circuit needs repair. These TV's have a tendency to burn through the main capacitors on the power supply board it's been a known problem for awhile yet they continue to use under rated caps. There is typically four of them usually the four biggest ones on the board all you have to do is replace them with new ones of the same capacitance value but of a higher voltage usually ones rated for 16v will do the job and you can even substitute with an even higher voltage rating so long as the capacitance value is the same as OEM. Good Luck

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Need a bit of help.

Really liked your insight into fixing my tv. Just need a little bit more help. I have the tech knowledge to be able to fix this if I know what I'm looking for. Would you be able to give me a bit more guidence

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Its Not the Power Supply Trust me

It not the power supply, I tried. Its the main board.

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That worked.

Read these posts last night and gave up on the idea of trying to find a fix for my LG TV. For the heck of it I thought I should at least try to unplug the TV overnight before I drove to Costco, Warriors playing tonight and I don't want to miss. Anyway all is well in TV land, no blinking light and TV working as before.

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Fix it

Your problem is loss connection GPU with mainboard
For fix this problem back cover
2.separate mainbord from metall cover dont forget disconnet all wire or flat connection with main board
3.remove big heat sink from main board you have to see one processor (LG-XD ENGINE)
4.reheat it with flux for 40 seconds
Now your problem is fix
If not fix , you must reballing this processor with infrared heater

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LG 42LN5200. Same problem.

I have a LG 42LN5200 and was working we turned off and went to turn on and screen is black. Red light is on and we hit power button again and 3 blinks and off. Always a black screen

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I Tried

I tried getting that thing off, pinching all of the little plastic posts. It was stuck on there--pulled far harder than I was comfortable with.

Is it soldiered on too? I could not find any other connections. I wouldn't mind trying this if I could get it off without snapping the mainboard. I replaced the mainboard and it did not work. But with sketchy supply houses, I had no idea of the one I tried to replace it with worked either.

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Easy fix

Take the entire main board out of the TV. Remove the metal outer edge. Preheat an oven to 385 degrees. Place the main board on a piece of corrugated cardboard for 10 minutes in the oven. It may smoke and stink or it may not. Remove it and let it cool for 20 minutes. Then reinstall in the TV. The trouble is years ago they stopped using lead in the solder used on boards so cold solders are now common. Cooking it in the oven is the same as wave soldering the board to redo all the solders. Look on youtube for a visual explanation. There is several videos on their about LG TV's and heating up the motherboard in an oven.

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Not saying this won't work

But I did this, twice. It didn't work.

I would love to have tried to directly heat up the XD-Engine, but sadly I think that metal plate is held on by more than just those little plastic things. I might have broken something just trying to pull it off after disengaging the little plastic tabs. I wondered why they even used them it was so tightly on there.

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Blinks 3 times no screen power

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(NT) EL problema son los led, no hay mas
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Same fault in 32lf5800

Hi. I have an lg 32lf5800 and I had the same error, power led blinks 3 times and no video or audio. The fault was in the led strips. I changed the 3 led strips in the repair service.
I had the led backlight at 100% and they told me that it is not recommended more than 50%. If you want more light, may use brightness.

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Red light

Yes. Had the same thing 2 days ago with our 18 month old smart tv. I’m told by the dealer that the power board is gone and will cost me $350 to fix it! I think, judging from what I’ve read, LG KNOWS ABOUT THIS PROBLEM. Would never buy LG again!

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