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Monday, June 3, 2013

Lightning strike killed the LG 55LW5700 TV - Fixed it!!!!!

This post is about repairing a LG flat screen TV.

Last night we heard a really close lightning strike that blew three breakers in our house.  It killed everything that was connected to my wired ethernet network.  It killed the FIOS box, my desktop computer (which was behind a surge protector), my ASUS wireless router, my son's desktop computer - just the ethernet port, the ethernet port on the Sony TV, and worst of all my fairly new LG 55LW5700 TV.

The LG 55L5700-UE TV is dark.  The standby light blinks slowly red about once a second.  Pressing the power button makes the light turn solid red.  No picture, black screen, no sound, no other life.  Pressing again and back to flashing slowly red.

I did buy this at Costco, less than 2 years ago.  I could take it back and play dumb and say that it just doesn't work.  However I know it was killed by lightning which the warranty doesn't cover.   Ethics aside, the kicker is that it is easier for me to fix it by swapping a board then haul it to Costco or ship it anywhere for repair.  It is a friggin 55" TV.

I suspect the power supply board, given the known power surge.
http://www.fixya.com/support/t17617660-red_flashing_light_tv_power_went_out
Some worries that the strike clearly traveled through my ethernet wires as well, my router was blown, and the set is using wired ethernet.   I might be replacing the main board too.

Found a couple boards around the net that say they are for the set, but part numbers vary.  The picture looks consistent.



  • LG 55" 55LV5400-UB 55LV355B-UA 55LV3700-UD EAY62169901 Power Supply Board(BX2)


To open up the set and check the board, I'd have to take it off the stand, unwire it, and remove about a dozen screws while I balance it on edge.   While that is unavoidable, I don't want to take it apart and let it sit there propped up for 3 weeks waiting for the part.  I'm going to pull the trigger and buy a new board without really testing or even opening the set to see which exact power supply I have.   In engineering we call this being a cowboy.   I'm going to make a 40 dollar gamble that this is the problem and that I'm buying the right board.  If it is totally wrong I can resell it on ebay.

Finally bought this one.   I'm taking a risk that it isn't the correct board.  Paid $59 + 12 shipping.  I had bought a cheaper one, but the seller cancelled the transaction saying the board was cracked.
BRAND NEW GENUINE LG POWER SUPPLY BOARD P/N EAY62169901 55LW5600UA EAX62876201/9
http://www.ebay.com/itm/271212434286?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649


Waiting for the new board to come... then I'll post pictures of replacing it.

The board came.


Took the TV off the TV mount and removed the brackets.   Took it down and leaned it against the sofa, so that is was still standing vertically with the screen against something soft.   NEVER lay a set like this down flat on it's face.   The glass can't support the weight and may crack.   Then I removed all the screws around the perimeter of the set.  Must have been 20+ screws.  this is the S/N tag.


The screws are all around the outside edge, and a few around the patch panel on the right.


The only tricky part is that there are a couple screws around the video connections, and the one I missed is in the middle of the RCA video plugs.


Once they were out the back comes right off.


The power supply board is right on top in the middle.


Squeeze the two sides of the power connection and it slides out.


The connectors slide out.  There are two types.  Some you squeeze the two sides and slide it out. A small screw driver can be used as a mini crowbar to separate connectors while you squeeze with the other hand.


  The others have a tab in the center you need to lift to unhook.


Luckily the part number of the power supply board was the same as the one I had bought, EAX62876201


I did notice that the new board is actually an older rev, Rev 1.0 vs the board in my set was Rev 1.1.   They look pretty identical so i'll forge ahead.


I put in the new board and powered up the set.  FAIL.  The set is doing the same thing.  The red light flashes and nothing else works.   You would have thought it was the power supply board zapped, but the surge hit the Ethernet on all the other devices so I should have known it was the main board.

This is the main board on the right.  It has a number of similar connectors requiring squeezing the outer edges and a handful of screws to take out.   The ribbon connectors on the left were the hardest.  Again squeeze the tabs on either side and use a small screwdriver to separate the connector.  Stick the screwdriver in a crack and wiggle and turn it.  A little finesse and they are out.



Here is the part number of the main board.


Found one on Ebay for $73.  Waiting for it to come.  Note that all these LG sets use the same board so it really doesn't have to come from the same type.
http://www.ebay.com/itm/261225522164?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

The new board came today.   It looked pretty much the same as the old one.  I didn't take the time to compare it exactly, I ran down and popped it into the set.  Attached the board with it's screws and slid in all the connectors.

It was not that exciting or difficult to install.   I plugged in the set before putting the cover back on.  Red light was no longer blinking.  Pulled out the remote, pressed power, and baaadaaaaaabing!   Win!  Set came right on, and the picture was there.  I had to reset up everything because of course, with an all new board it had forgotten all the internet SSID, Netflix passwords, etc.



The hardest part was actually getting the cover back on.   I propped the TV set up against the sofa and worked on it vertically since you never want to lay a big TV flat.   When i put the TV back on, it was tough to line up the screws and keep the front plastic bezel from popping out.   I had a couple extra screws when I was done.   Once I slipped and the set almost fell over.   However all was good.

Since the board was from a 47LW5600 not a 55LW5700 I need to go into the service menu and reset the set type and turn on some of the features, like the audio settings.  I covered that in another post, you need the correct universal remote and the password.   This isn't absolutely necessary, the TV works fine it just thinks it is another model.  Some of the video modes, local contrast options are turned off.
http://blog.workingsi.com/2012/02/hacking-lg-55lw5700-tv.html


My new RCR312WR.  See the Guide button.
Put in the 5 digit code 11265 on this one.  Hold the TV button and type it in.  

Went to the TV and pressed the guide button.   Enter 0413 as the password. 
Press guide and the code box pops up.   Type 0413
Adjusted the TV model and size back to 55" and turned on the picture modes, audio, etc.

Anybody with  Philips head screw driver, some patience and an Ebay account can do this repair and amaze your friends.  Even other electrical engineers were amazed I took this on.  You have to have faith that sets are modular and easy to open and swap boards.  If they weren't they'd cost the manufacturer tons of money. Back in business for <$160.   It might have been half that if I had replaced the main board first.  I could resell the power supply board, but I'd have to put it back in and prove it was good before I could sell it, and I want to get on with life.

Since I did this I did some more googling and there are youtube videos on the process, which i haven't looked at.

46 comments:

  1. Hi, I just found your page with your great DETAILED information… which by the way was very difficult to find (I’ll explain later). I too am going through the same scenario (around 99%) of the problems you had faced in June 2013. I will get back later and explain in detail but right now I need to order the BU board (Board-Up) alias Main Board… so many terms without definitions.
    FYI: Mine is a 55LW5300 3D TV

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  2. Cool... that makes it worth my time to make the post if it helps somebody else!

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  3. you are a life saver just made that same mistake on my 55LW5600 that i scored
    on craiglist for $200 Thanks

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  4. Same problem with my 1 year old 55LN5710. Lightening killed the router and all the ethernet switches in the house. Do you think your TV would have worked just by replacing the main board?

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  5. Sorry missed the last question while I was away. Yes, just the main board, the power supply board was fine.

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  6. My LG 55 inch will not even turn on after lightning strike.. What should I do..please help

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  7. Is the power red light flashing or is it dark? Did you have wired ethernet plugged in or not? Go on ebay and buy the motherboard if the light is flashing (more likely if you had an ethernet cable plugged in). Buy the power supply board if it is not. you can fix it for $60 if you have a screwdriver.

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  8. I'm not sure if its the main board or my power supply. I didn't have an Ethernet cord plugged into the main board. The red LED is always on, not flashing. What do you think?

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  9. Tough call, it could be either. Since the LED is on, you are getting some power. I assume there is no sound and no picture. You didn't have ethernet plugged in, so the lightening should have zapped the main board in the same way it did mine. Did any of the components plugged into HDMI fail? Zap might have entered via HDMI. Look at the power supply board carefully and see if there is any black marks or bubbled capacitors if not, although somewhat a guess I'd buy the mainboard first. If that doesn't fix it you can always buy the supply board and sell the main board back on ebay. It will be cheaper than buying a new set even if you have to buy them both.

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  10. Yeah I had the cable box plugged in through the HDMI. The cable box also failed. Now I'm pretty sure it's the main board but I will still check for some damage before I buy anything. Thanks.

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  11. I have same model tv. Last week there was a snowstorm and we lost power for a second and had sone flickering lights twice during the day. Now tv turns on and has picture but no sound and makes a constant clicking sound. Do you think is just the power supply board ?

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  12. Catherine - the question is, did anything else plugged into it break too? Your cable box? Your speaker system? Your internet? That can give you a clue about what the source of the failure was. Have you tried plugging in headphones in the back? Does that sound work? My first guess is you fried just the audio chip on the main board. Did you have some sort of red/white RCA plugs to a video game or external speakers plugged into it?

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  13. The only thing connected to it was the dvr box from directv but that is working as I can see the channels from directv but theres no sound. I'm going to try plugging headphones in the back to see if I get audio. If the audio chip was fried, how can I fix it?

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  14. I plugged headphones to the back and I get the audio. So I guess the speakers from tv are not working and the clicking sound comes from there. It is a constant and rithmic clicking.

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  15. You get the audio from the phones, but does the clicking from the TV speakers go away when you plug in the headphones? In other words , now that the headphones are plugged in, and not in your ears, do you hear clicking from the TV.

    Honestly the speakers on this set are so bad anyway, I recommend you get a set of $20 computer speakers, plug them into the headphone jack and call it an upgrade. It will work just like it does now but sound better. I use some logitec speakers like these that you will be amazed how much better the TV sounds. That is much better and cheaper than popping this thing open and swapping the boards.

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  16. Same problem with my LG 55LW5700.
    I confused to buy a board. My board code EAX64294002(1) , I just get this code EAX64294002(2). Is this compatible ? If compatible i just make hole for antena input...

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  17. Hi! We had our LG affected by a lightning strike as well. The cable boxes were fried! We replaced the power supply today and that seemed like it fixed the problem for 30s. Looks like we'll be replacing the main board too. Thanks for posting!

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  18. Hi: Our LG TV (mod. 47LV3700) was lightening struck and lost its input signal through the HDMI source and any signal when a tape deck was attached with acoax cable directly into the back. The set will come on and I can pull up the input menu, then the LG symbol dances around the screen with a "no signal" bar across the top. Which board is needed in your judgment?

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  19. 100% it is the main board. Just go on ebay and search the model number and "main board". Open it up, swap the boards and you will be good to go.

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  20. I have a 47lw5600 that I dont know the history on. WHen plugged in I have a solid red light. When I turn it on via remote it blinks red a few times then goes to blue. It stays blue. No picture no sound. I just connected my chromecast to the hdmi and usb to see if there is any power on the hdmi board and no power.

    Could it be the power board? or the main board or tcon?

    thanks

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  21. Sure sounds like the main board to me.

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    Replies
    1. I have a 55LW5600. no picture or sound just now. no electrical storm or power surge that I'm aware of. when turning on directly on TV, the red lite blinks, then the blue light comes on solid, but no picture or sound. Any thoughts?

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    2. I don't have debugging information so absent any information on how the set got this way, this sounds like an ebay part swap candidate. I'd troll for a cheap motherboard on ebay (some have said recently they are getting harder to find). Swap it in and chances are good it will be fixed. If not, you can always sell the motherboard you bought back on ebay and probably break even.

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  22. I checked the power board with a volt meter (first time ever using one) THe power on pin shows 3.5 volts. but it should be 24 volts.

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  23. KK, I have the exact same issue on 55LW5600. Please let me know which board fixed the issue

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    Replies
    1. Bake the mainboard in the oven set it on card board 375 for 10 min.then let it cool for about 1 hour with oven door open.fixed mine can't buy new board lg discontinued it

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    2. Prior to reading your post. I ran a hair dryer on mine and could get it to work every once in awhile. Tried to isolate it to a certain part of the board or specific component, but haven't figured it out yet, other than a hair dryer helped. Do not have component cooler..... yet.

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  24. Hi my tv was working fine now has screen issues on left hand side with a strip of light had a lightening storm the night before

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  25. I m from malaysia. Hope u all ok with me . my name yazid

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  26. I am trying to find a Main Board for 55LW5600 and it's out of stock on every website. The part number is EAX63969204(0). Appreciate if anyone help finding this Main board.

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    Replies
    1. Try YouTube trick baking it on a piece of cardboard for 10 minutes at 375 leave it in to cool for 1 hour then reinstall.worked on my 55lw5600

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  27. I have a LG 47LW5700 model with same problem red light blinking slowly, can I use the EAX64294002(2) mainboard?

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  28. I have a LG 47LW5700 model with same problem red light blinking slowly, can I use the EAX64294002(2) mainboard?

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  29. I have a 32lf565b lg TV, same lighting problem, can anyone tell me where to get the mainboard # eax66107204

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  30. Thank you! This saved me $$$. It was the main board. Fixed it in less than 30 minutes once the part came.

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  31. I replaced my main board with one I found on ebay in Poland. Now everything is European. Can I reprogram this main board for US? It is not a country option in setup.

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  32. This comment has been removed by the author.

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  33. Thanks so much!! My LG TV died after a lightning strike and the red light wasn't flashing at all. Followed your instructions to order a new power supply board off Ebay, replaced it and it works great again.

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  34. GREAT information! Thank you for taking the time to share this. I've looked at a lot tech forums, video etc. So far your the only one who warned against laying the TV face down (which I was planning on doing) and the LG boards being the same. I'm going for! Thank you again!

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  35. Power boards you can still get but the mainboard is harder to get check YouTube about baking it it worked for my 55lw5600

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  36. OMG, I searched for the Youtube video about baking the main board in the oven and it worked! I baked my board and now my tv is working again. Unbelievable! LOL! Here is the link: https://www.youtube.com/watch?v=Vz_AGCXrTy8

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  37. Hi I have a LG 47ln5700-UH tv and the it isn't working. When i press the power button, the stand by light just flahses 3 times then goes off. Screen or nothing turns on. Any ideas? I have switched the power supply board already.

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  38. I haven't had good luck with this brand.
    My family bought 4 LG tvs. All 4 had a problem.
    2 tvs start with vertical lines when powered on and only after 1 hour I get good image. One of them is the LW5700 and the other is LD650.

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