LG LCD TV 42DL550 Fix

How to repair an LG LCD TV main board.

 

This is a simple method to fix a TV or other electronic device with bad solder connections.  The TV I fixed is an LG 42″ LCD TV Model 42LD550-UB.CUSWLHO.

Symptoms

The TV would power on and the LG Logo screen with the clock would appear.  It would freeze on the logo screen.  It was stuck there and would not boot any further.  The none of the buttons would work.  It was totally stuck.

First I tried unplugging it for about 15 min to reset everything, but that did not make a difference.  Note:  It’s always good to try this first on any electronic device.  Also if the device has any kind of factory reset button, always try that as well before taking it apart.

I searched around online and found other people reporting issues with this TV.  HDMI ports not working, no inputs working, Lines on the screen, fuzzy video, etc…  It seems many different makes and models are affected.

I removed the board and I did not see any physical damage, no components looked fried or burnt, no capacitors looked bad, and all the connectors looked to good.  This lead me to believe the main control board Model EBT60955753 LG MAIN (3642-1052-0150) could have one or more bad solder joints.

This TVs was purchased in 2010 and out of warranty.  A new board was hard to find, and too expensive.  I decided to try this simple repair myself because I had nothing to lose!

Summary

To fix it, I baked the main board in a electric oven for about 10 minutes at around 385 °F and It worked!

Explanation

Why did this work? After heating and cooling for years, tiny cracks can form in the solder connections.  Heating the board to 385° F (above the solder melting point) caused the solder to melt and these cracks flow back together.

Believe it or not, this trick works on more than just this TV.  This can fix a long list of other electronics.  It’s not uncommon for manufactures to under cool their components, and/or ship electronics with bad solder.  Poor ventilation, bad fans, small heat sinks, dust, stress, and other factors can also cause over heating or cracked solder points.  Even a very tiny crack that you can not see can cause a bad connection.

Warning:  Attempt at your own risk!  Safety First! Always wear protective gear when working on electronics.  Safety Glasses, Gloves, etc…  Remove Electricity from the device (unplug) to Avoid Shock!

 

Again, attempt at your own risk!  This will void your warranty, and possibly damage the board.  I have only tested this on an LG 42DL550!  Other readers have had success on different models so search through the comments.  I would only try this if the TV is unusable and you have nothing to lose!


Let’s Do This!  Step-By-Step DIY Fix:

 

– Remove the board from the TV

LG MainBoard EBT60955753 (3642-1052-0150)

LG LED TV Control Board EBT60955753 (3642-1052-0150)

  • Step 1.  Call LG and complain.  Everyone complaining to LG might make them understand how unhappy people are, and they’ll see this is a known issue!  Maybe if you play your card right, they will admit this is a fault with their product and send you a replacement.
  • Step 2.  UNPLUG THE TV before you touch it!  Electric shock can cause death!
  • Lay the TV down on its face. (Put it on a blanket to be careful not to scratch the LCD)
  • Remove the stand from the TV. (remove the four long screws at bottom and the stand slides out)
  • Remove the back cover from the TV.  (don’t forget the screw near the power plug, and the one in the middle of the input jacks.)
  • Take pictures of the Board from all angles.  Make sure to get good ones of all the connections.  You can use these pictures later to make sure you reinstall it correctly.
  • Remove all the connections. (Be gentle, they should come off easy, if you are doing it correctly)
    • How to disconnect them isn’t obvious to the inexperienced.  Use the picture above for reference. (Click on the picture to enlarge it!)
    • On the upper right there are two ribbon cables. To disconnect these, gently lift the thin black plastic strip on the connector (it flips up), then you can pull the ribbon cables out.
    • On the lower right there’s a wide header block with gray wires. Squeeze the sides (opposite ends) of the connector to release it and pull up.
    • On the upper left are two other connectors. In the center of these is a small plastic part. Press down gently on the edge of that (the edge near the wires), causing the opposite edge to lift a bit to unlatch. While pressing, pull gently in the direction of the wires, away from the board.
  • Once all the wires are disconnected remove the six (6) screws holding the main board to the frame.
  • Remove the black plastic face plate from the side input jacks. (No screws, it’s held on by it’s plastic clips).

– Bake The Board

  • Now we are going to bake it in a conventional electric oven.  (Do NOT use a microwave, gas oven, open flames, Air Forced Heat, or any other type of heat!)
  • Why not use a heat gun?  A heat gun is forced air like a hair dryer.  As soon as the solder melts, the air will blow the components out of place, or even go flying off the board.
  • Why not use a gas oven?  Open flames can be dangerous in this situation.
  • Why not use a microwave?  Never put metal in a microwave!  Very bad things can happen.
  • Preheat the oven to 385 °F (196 °C)
    • The correct Temperature is IMPORTANT.  If you don’t trust the temperature setting on your oven, or if your oven does not have a temperature setting, then get a baking thermometer and test your oven!
    • 385 °F is working for most people, but there are different kinds of solder.  Altitude and humidity might also play a factor.  Most solder melts between 360 and 419 Degrees Fahrenheit or 180 – 215 Degrees Celsius.
    • Solder is a mixture of Tin and Lead.
      50 Tin/50 Lead: melts between 183–215 °C (361–419 °F)
      60 Tin/40 Lead: melts between 183–190 °C (361–374 °F)
    • NOTE:  These temperatures might sound scary, but the ignition temperature of paper is around 451 °F so these components should not be damaged at these temps in an electric oven.  Again, this is why we only us an electric oven.  No open flames!
    • See https://en.wikipedia.org/?title=Solder for more details about Solder.
  • Place the board face up on something nonmetallic like a piece of cardboard.  A pizza round or similar works well. (Do not put it on anything metal because the solder will stick to it.)
  • Place it on the center rack of the oven.
  • It will smell funky when cooking so you might want to open a window and/or turn on a fan!
  • Let it cook for about 10 min.
  • Turn the oven off and let it cool.  (Be careful!  It’s hot and will burn you!  Use oven mitts!)
    • Do not to bump or disturb it while it is cooling!
    • I would not move it until its below 300 °F, so you don’t disturb any components!
    • Just turn the oven off and leave the board in it with the door open until it’s cooled off a bit.
    • If you take it out of the oven while it is still hot, remove the board very carefully, let it cool at least 30 min before you touch it.

– Install and Test

  • Install the main board in the reverse order that you removed it. (Refer to your pictures)
    • Make sure you get all the cables in the correct location.
    • Double check each cable to make sure it’s connected correctly.
    • Check your pictures to make sure you have everything correct.
    • You might want to leave the back off until you test it in case it doesn’t work, and you need to bake it again. Just do NOT touch anything back there with it plugged in!  BE SAFE!
  • Turn on the TV and see if it works.  (Note:  Wait at least 10 Seconds after turning it on because it seems to take a long time for this particular TV come on.)
  • If it does not work:
    • Try cooking it again for 15 min.
    • 10 min. worked for me on the first try but results my vary…
    • Try a higher temperature 183 – 215 °C (361 – 419 °F) as noted above.
    • One reader noted he went all the way up to 482 °F (250 °C ) although I highly recommend staying below 425 °F.  I’m guessing his oven settings are off.
    • Another reader said he put a weight on the LVDS chip while baking and that worked.
    • Read through the comments, there’s a lot of good info in there.

Please comment to let everyone know how it went for you!  Include the Make and Model of your TV / electronic device to help others can find this post!

Warning:  Attempt at your own risk!  Safety First! Always wear protective gear when working on electronics.  Safety Glasses, Gloves, etc…  Remove Electricity from the device (unplug) to Avoid Shock!

 

Again, attempt at your own risk!  This will void your warranty, and possibly damage the board.  I have only tested this on an LG 42DL550!  Other readers have had success on different models so search through the comments.  I would only try this if the TV is unusable and you have nothing to lose!

 

Keywords:  Samsung, Sony, Vizio, Sharp, Sony, Insigina, Toshiba, JVC, Philips, Magnavox, Sanyo,  Fix, Electronics Repair, Motherboard, Mainboard, ControlBoard, CPU, ReSolder,

471 thoughts on “LG LCD TV 42DL550 Fix

  1. I have this exact TV. All 4 of my HDMI ports went out about 3 days ago. Last night, i found page and a few similar to it. I read all of the posts and figured, it cant hurt to try. My setup required HDMI.

    Anyhow, i first unplugged the TV for 15 minutes. That didn’t work. Then i took the TV apart. I then loosened the board and tightened it back up and tried my HDMI ports again. That didn’t work. I then removed the ribbons and put them back in and tested again. Didn’t work. So i fully removed the motherboard and just like in the pictures and the you tube videos I’ve seen, i put it on some thick cardboard and baked the board in the oven at 350 degrees for 12 minutes.

    Fortunately there wasn’t any smoking and it didn’t stink up the kitchen.

    I let the board cool for about 15 minutes and was able to put it back into the TV.

    I have to say, i’m totally floored that this worked. All 4 HDMI ports started working again.

    I’m pleased to say… this really does work. The entire process took less than an hour. 5 minutes to take the TV apart and remove the board, 30 to cook and cool the board, another 10 to reinstall and get everything right.

    I hope this helps others. My TV was also bought in 2010/2011 window, same as all these others.

  2. I have done this twice already. The first time it worked just fine but the effect only lasted for about 6 months. Eventually the HDMI ports all stopped working again and even the compisite connections stopped working too. I baked my board for 15 minutes this time at 220C. I let it cool down for about an hour and voila… My LG TV is now fully functional again. I suspect the effect will only last for several months but the whole job only takes about 1 hour now that I know what I’m doing so I will probably keep doing this until the thing doesn’t work any more. A friend told me that the fumes are probably quite toxic so next time I will just leave the house for the whole period and make sure there is good ventilation in place. Anyway, for the time being I’m very happy to have my HDMI connections back (and my remote control and composite connections too). Thanks for sharing this post.

    Happy baking.

  3. My LG 42LE5350 had the same problem. Powered on and stuck on the logo with blank clock screen. Saw this post and decided to try.

    I used a cheap ($8.99 with coupon) heat gun from Harbor Flight so I don’t need to bake the whole circuit board. I opened the TV, remove the circuit board, remove the heatsink in the center to expose the chip. Used heat gun (low setting) to blow directly on the chip for 35 seconds. Let it cool for 5 minutes, put everything back and it worked again.

    Thank you.

  4. First of all forgive my english i’m an italian living in Spain. I want to say thanks a lot to Zedic for his fantastic idea that make me give life again to my 50PK950 plasma LG tv.
    I put the main board “cooking” for 10 min at 190 celsius and …problem solved.
    Thank you again.

  5. Well worth a financial contribution to Zedic.com! I followed the instructions and it worked first time! I have a LG HDTV, model 42LD520-UA. One would think that the entire board would deposit a pool of solder in the oven, but this quick and EASY fix is outstanding. Thanks.

  6. I was skeptical, to say the least, but most sites I visited were out of stock for a replacement board. I figured I would give this a try……. OMG ! It worked like a charm. Just follow the directions outlined and hopefully you will get the same amazing results….. definitely worth the time and effort. Took about 1 hour total. Thanks for the info…..

    Cheers, Vince

  7. We just did it, 10min at 385 and it worked! My husband sang hallelujah. LOL. Thanks so much, if I didn’t have this we wouldn’t have a tv, as we don’t have money for a new one. My kids would be missing their Care Bears. 🙂

  8. Yesterday my LG 47LD650 (purchased in 2010) just lost the picture while I was watching it, no “clicks” or other noise, just a fade to black and then a floating “no signal” on the screen; audio, however, kept coming through the receiver. Tried all HDMI ports, tried HDMI from cable box directly, then tried component hookups, etc., no go. Then tried hooking up another TV, worked fine, so I knew it wasn’t the cable box or receiver. While the “bad TV” “INPUT” menu recognized the type of hookup (HDMI 1, HDMI 2, component, etc.) I still got “no signal” bouncing around the screen. TV menu test of picture and of audio was positive–screen worked, speakers worked–so, exasperated, I went online and immediately found this “fix.” I was skeptical, of course, but I know someone who had worked with LG, texted him, and he said he had worked on this issue, said the procedure is called “reflow of motherboard.” With nothing to lose (way beyond warranty, had visions of putting the TV on the curb and rushing to buy another–what, with Game of Thrones 32 hours away!), I went for it . . .

    And it worked. My gas oven is very old and it’s hard to get a specific temperature, so for me, the baking worked out to be about 8 minutes starting at 375 and increasing to 425 degrees F, taking the board out when the oven hit the higher temp, as per the posted high temp caution. The unused HDMI and USB ports had a lot of dust in them, so prior to baking I blew them out with canned air, lest “baked dust” made them unusable. This is a terrific fix, very satisfying to “accomplish” after previously thinking a new TV was very prematurely in my immediate future. Hope the fix keeps, at least through the duration of the Game of Thrones season–takes me at least two months to shop for a TV!

  9. I used this procedure on my LG TV and it worked great. It saved me the cost of buying a new TV. The TV is approx 6 yrs old. I see no reason that the TV wont last more years. It all makes perfect sense concidering curcuit board heat and cool many times which can cause partial failures within the connections. Follow the procedure exactly, dont rush.

  10. Wow! You just saved me at least $251 + shipping from Australia, and probably $2000 for a new HDTV. This procedure worked exactly as stated. 12 minutes @ 385 F, reinstalled the PCB and all HDMI inputs are working normally. As a DIY’er it was relatively easy to remove and replace the board. The only snafu was removing the ribbon cable. It wasn’t immediately intuitive to lift the black plastic bar to remove the ribbon cable, but this article referenced that technique. Amazing that a simply repair can save so much money, clearly there is some defect in the manufacturing or quality of the solder on these boards. Not sure if that is an LG or supplier problem.

    Thanks again for taking the time to post!

  11. Must admit I was skeptical at first, but came to the conclusion there was nothing to lose. Tried the baking method as described within the post and was delighted with the results.

    Thank you for sharing this Zedic, you are a savior in my book.

    Thank You.

  12. It’s Incredibly efficient!

    TV Model: LG 42LD840

    My issue was very similar to one I’ve read here, when I turned the TV on, several horizontal lines started to flickering, this symptom went disappearing gradually and the picture was showed perfectly after about 15 minutes depending on the temperature of the environment, if it was cold it lasted 30 minutes or more, in the sweating summer (I’m in Brazil) it lasted less than 10 minutes, but just a reboot was necessary to bring the issue back.

    Unlike some of the friends here, ever since I found this article I believed it could have a sense as I already suspected that the issue was somehow related to a bad solder as the TV worked only after a period of warming.

    So I decided to try, but I had to do it twice:

    First atempt:
    1 – 5 Minutes to disassemble the TV and reach the mainboard.
    2 – Sat the oven to 180C-210C and put the mainboard inside (I didn’t have a cardboard, so I used a Bake glass tray, glass is non-conductive and it worked for me), left it there for 12 minutes.
    3 – I chose the cooling method 1 so I took the MB out of the oven and left it cooling for 15 minutes.
    4 – 5 minutes more to reassemble the TV and turned the TV on.

    The picture was with some flickering lines only at the top of the screen, so I doubled checked the T-con ribbons and after that the result looked fine, but the symptom just went back about 30 minutes later, then I decided to do it slightly different.

    Second and successful Atempt:
    1 – Sat the oven to a higher temperature: 210C-240C.
    2 – Left the MB inside a bit longer: 17 minutes.
    3 – This time I chose the cooling method 2, so I just turned the oven off and left the MB cooling inside the oven with the door open for 50 minutes, I noticed that the smoke generated in the process of cooling was more stinky (due to baking in higher temperature) and lasted longer to stop smoking (due to smoother heat exchange).
    4 – 5 minutes again to reassemble the TV, turned it on and at the first attempt it worked pretty fine.

    It’s been working for 2 weeks now.

  13. I followed the instructions an it works. My only caveat: don’t put the back on until you’ve tested it. I had to take the back off twice because I didn’t get one of the ribbon cables reseated properly an had only half a picture. After a bit of fussing, it is working as good as new.

  14. 46LD550-UB – stuck on boot at logo. Followed instructions exactly (10min @ 385) and it works now. Love the simple fixes. Thanks for posting this.

  15. Just applied the fix to my 47LD650 set (built in 2010) – 12 min @ 385 degrees, and now I have video again through HDMI…however, audio is now dead – any ideas?

  16. Wow…unbelievable! It worked!!
    Model: 55LE5400 (or 55LE5400-UC)

    I bought this in 2010 and last week while watching Netflix (via Roku), all of a sudden the picture went away and I got the ‘No Signal’ message. First I thought it was Roku or the HDMI cable. I tried another cable, same problem. I tried connecting my PC to the TV via HDMI, again ‘No Signal’. I tried all HDMI ports but all gave the same ‘No Signal’.

    I wasn’t ready to believe that all HDMIs would stop working at the same time. Then when I googled the issue, I came across this site and saw the huge number of people having the same issue.

    Called up LG and as expected they said the warranty had expired and gave me two dealers to call who can do the repair. One guy said it will cost $135 (Labor) + $260 (part). The other one said to try shopjimmy.com and find the part, though it may be out of stock.

    Then I opened up the back as described above and noted down the part number and tried to find the replacement board on ebay. No luck, it was out of stock everywhere. Figuring I had nothing to lose, decided to try baking it (feels crazy saying this considering I have a bachelors in electronics).

    I pre-heated the oven to 385Fand then put the board in a Pyrex dish (glass) the same side up as in the picture above. Then baked for 11min and let it cool in the oven (opened the door just a bit) for 30 min. Then took it out and let it cool for another 15 min.

    Installed it back and it worked!!! All HDMIs are working back again. Its only been a day but it has saved me from spending on another TV for some time.

    Thanks for posting this. A super thanks is on its way!

    1. Wanted to add that at first when I opened the back, I took the board out, dusted it off (it was mostly clean), and put it back in. I figured the reason for the fix might be some loose connections (and not the baking). But that didn’t work. That’s when I decided to bake away!

  17. June 4, 2016, Baked the HDMI ,board as described , 385 F for 10 minutes, let it cool in the oven, reinstalled and so far it is working great. Previously all HDMI and component inputs did not work, they do now.
    Thanks for your help.

  18. Great job!
    LG 47LD650 image flickering for 10-15 minutes and then works great. Did the baked stuff at 200C for 11 minutes. Works now perfectly.
    Thx you

  19. A few years ago the HDMI ports stopped working on my now 5.5 year old LG Infinia 47LE8500. The component video ports and TV input stilled worked, so I made due. This morning the TV wouldn’t get past the startup logo screen. So I tried the oven baking procedure and now the TV is working like new. I’m not sure how long it will last, but I’ll keep my fingers crossed. I expect better quality and support for what was at the time a $1,200 purchase. I haven’t purchased another LG product since.

  20. I am so excited that the baking method worked on our LG LCD 42DL550 TV!!! Like others the TV was frozen on the start up screen. Since I have 2 college aged kids, I left them to attempt a fix. Nothing worked. In the meantime, I started researching online on my phone, and the kids just rolled their eyes at me believing I never get it right on tech stuff. When I discovered this baking idea, they thought I had really cracked up, and that I had only discovered some troll on the internet. What a stupid idea, right? What made us decide to try it was the well laid out instructions only zedic provided, including the explanation of why this worked (along with a picture), and that we had nothing to lose! My husband came home from work, and he agreed to go for it, and so it became a fun family project. HA! I have been redeemed!!! It was ME, the dumb mom’s idea to do this! Now we don’t have to go out and buy a new TV when we really can’t afford it! I appreciate the post where someone had to do the baking a second time after about 6 months, but it still worked! Yay! Hope for the future! Thanks, zedic!

  21. Here’s another succes story, it was a 32LW579S from Feb. 2012 with the same BCM23230 chipset that zedic has picturized in his article – only this here comes with a larger heatsink completely covering the chip. Board is tagged EAX64405501 and is used in more models from LG. This TV only had the flashing red light and a clicking relay when powering it up – nothing else although measuring showed that all voltages including core and 2,5V were present and no ripple was on them. A few weeks i put it away and the customer bought a new TV as a new mainboard was around 90 Euros and not worth it. When i read at Toms Hardware of Zedics fantastic discovery i decided to give it a try – nothing to loose anyway. After the first run it already came up with a picture (Yay!) but some bits on the LCD were still missing – looked like a posterize effect or so. I then put it in the oven again with a weigth placed on the LVDS chip (small heatsink left to the BCM and next to the ribbon connectors) and voila – this time it worked completely. Put some WD-40 on the ribbon connectors before plugging them in and now i was able to enjoy EM soccer in Full HD! Thanks Zedic and sorry for the lengthy post, but i wanted to mention the mainboard description for others with the problem.

  22. Nice one – worked a treat. Only Issue I am left with is some light bleed to the side, presumable this is down to over tightening of the video board mounting screws. Will readjust tomorrow.

    It’s interesting so many LG screens from the same era are being affected in a short space of time. Are other manufacturers screens prone to similar?

  23. Hello. I have a LG TV 55ub8500. HDMI does not work only. I tried to bake twice, the first of 385 F for 10 minutes, the second 420 F for 15 minutes. And still does not HDMI :/
    . Help me. Thank you very much

  24. Just tried this out this afternoon on a 6 years old Philips TV that suddenly stopped recognising all 4 HDMI ports. Tried all other easy tips like restarting, factory reset, install newest software, use another HDMI cable…. nothing worked so I had nothing to lose…. thus I used this ‘trick’ ( 10 min at 180°C )and succes ! Much appreciated !

    1. Typically this means you didn’t get the cables reconnected correctly. Go back to your pictures and make sure you have all the cables in the correct place and check to make sure they are tight.

  25. I verified they were connected in the correct order. I will check again to make sure they are secure again when I get home. One of the hdmi ports came losecand was inside the tv so before I did the bake I placed it where it should go and now it is secure, I hope that did not screw it up

  26. Hi,
    LG 42LE5500, manufactued on August.2010, all HDMI went out.
    After reading round the globe I stopped here at this stellar blogpost. I didn’t like to pollute my oven, so I used a handhold heat gun at about 300C. First of all I had to remove the heatsink on the main processor chip. It’s fixed with plastic clips and I was in fear they will melt at more than 100C. Next I located all the other “Ball Grid” chips (BGA) and grilled every single piece at a distance of about 3cm for 5 to 8 seconds.
    WOO, the TV is working again.
    Though I’m a well educated “Electric Guy” and I know about fuzzy solder joints, I was scared about baking my TV. But all these success stories here brought me further.
    Many thanks to ZEDIC and all the other brave girls and boys posting their comments here on.

  27. Fantastic! What a great fix! I have a 65″ LED LG (I didn’t document the model number, apologies) and all of the HDMI ports fell one after the other. A quick Google search led me to this post! For me, because of where the TV is mounted, it was about a 2 hour job. But once it was down, the process took a little less than an hour! After about 40 minutes of getting the perfectly centered hang, we fired it up! We had picture!! Who would’ve thought baking a motherboard would be the solution!! Thanks!!

  28. All my HDMI ports on LG 750LD weren’t working any more, everything else worked just fine. My tv is 5 years old, but still very good. Today I backed my mainboard as it is described above – now when I turn my tv, the red LED flashes twice and the screen is black.

    No logo, no cube – nada. I did a flaslight test – nada. I checked if all the cables were connected correctly and tight – nada.

    What else can I do? Did I just killed my tv for good?

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