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,

434 thoughts on “LG LCD TV 42DL550 Fix

  1. I was skeptical (mainly that I would screw it up) but it absolutely worked on my 55LE5400 TV bought in 2010.

    Followed directions exactly (almost gave up when the picture was bad after I plugged the cables back in – I had to go and adjust the cables a few times – after the third time with the cables it worked like a charm).

    A million thanks!

    1. it worked well after the baking except that I damaged the ribbon cable while trying to adjust the correct plug-in position as it was giving me half the screen. Wonder how I can replace this ribbon cable now?

  2. I had issues where my 46LD550 would only display 720p all of a sudden, whether it be my PS4, WiiU, or Xbox 360. Eventually it would flicker even at 720p. I cooked the board per the instructions and right away I have 1080p back and I’m loving the clarity! Thanks for putting this together, it’s been great to see everyone’s feedback.

  3. I bought an LG Infinia 50PK750 plasma in October of 2010. It worked great until November 4, 2016 then all the inputs went out suddenly. I baked the board at 385F for 12 minutes and it worked! Until 2 days ago. On February 20, 2017 the same symptoms came back. I have just baked the board again, this time at 400F for 15 minutes. And it has worked for a second time. The first time lasted for 3 1/2 months. We shall see how long it lasts this time with a longer bake time at a higher temperature. Some of you had asked how long this fix might last, and I just wanted to present my experience. Next time it happens, I’m getting an OLED! I registered so I could post on here, because this fix has been a tremendous help for me, and I’m grateful. Thanks Zedic!

    1. I baked by board Nov 20 2016 and mine just died again too! I am about to bake it again… funny that our lasted about the same amount of time. I will bake mine at 400 degrees for 15 minutes as well and we can check back here once they both die again 😉

  4. Hey everyone,

    On November 20 of last year (2016) I successfully baked my TV (see my post on that date). Just two days ago all the HDMI ports died again. So that gave me 3.5 months of borrowed time…

    I am going to try to bake it again and will update with the results.

    Ben

  5. THANKS!

    I am from Brazil and your solution worked out for me, just want to say thank you! I think you are helping much more people than you could imagine.

    tv model – 50px950 – all hdmi ports not working

  6. Just fixed an LG 55LE5400 (55″ LED/LCD, circa 2010), using a modified version of this oven reflow method.

    Issues:
    -Horizontal lines of white snow, on some parts of image more than others.
    -Large horizontal green blocks across entire image. (occassionally)
    -Issue occurs for inputs AND TV Netcast and setup menus (not cable or input related).
    -Issue came on pretty suddenly.

    Troubleshooting:
    -When I put pressure on the main chipset (in the middle of the board, pushing on top of the heatsink), the issue goes away. This confirms the molten solder balls underneath the chip are at fault.

    Solution:
    -Placed on cardboard, cut small square hole on bottom of cardboard so main chipset (middle of board) can get some underheating…like the board gets when you do a professional reflow. Placed mainboard roughly in the middle of the oven.
    -Turned temp to 420 degrees. (Board is inside while it’s warming so the temperature will ramp up gradually.)
    -Once it reached 420 degrees, set a timer for 10 minutes.
    -Once timer went off, set temperature to 425 degrees and set timer for 5 minutes. (Note the melting point of lead free solder, used in all modern ROHS-compliant electronics is around 422 degrees. This is why I chose to go higher than some people. Still, I didn’t want to go too high, or else start melting plastic.)
    -Once timer went off, turned oven off but left door closed, so temperature would ramp down slowly…for about 5-10 minutes.
    -Cracked open oven a little so board will start to cool a little bit faster.
    -Once board is in the warm to cool state, took out and let cool completely.
    -Once board is cool, reinstalled and tested. Issue resolved! Let’s hope it lasts more than a year! =)

  7. Worked Perfectly Fine for LG50PZ650 50inch Plasma TV.

    It was turning ON but no picture and no sound. Disconnected Z-sustain board still nothing, Then disconnected Y- sustain board and still nothing. So took a shot and removed the main board as shown above. Place it on cardboard in the oven. Bake it for 200 degrees celcius for 10 mins. Cool it for 20 mins and put it back. Shazaaam. TV started working again. Thank you so much my friend.

  8. Just baked my 42DL550. This tv was given to me because it wouldn’t pick up any stations, just white noise (static). Was going to replace main board until i came across this post. I’m thinking, “bake the main board” ???? After reading, it seemed to make sense. So i went ahead and “baked the main board” at 385 degrees for 13 minutes on cardboard, let it cool, reinstalled it, checked it out and VIOLA. Worked like a charm. Love my new FREE tv.
    Thank you for the most awesome post

  9. Magic! My LG-42LD690 made in 2010 had no sound at all, but picture was working perfectly. I tried this only because of the amount of the comments and it worked like a charm! Thanks for saving all the electronic waste. Oddly, there seems to be many comments for TVs from 2010.

  10. I was pretty sure this wouldn’t work but like others had nothing to loose.

    LG Plasma TV 2011 model 50PZ950 -TA

    Turns on. Backlight works. No picture. No sound. No menus.

    Remove main board and put on cardboard in oven at 200 C for 10 mins. Turned oven off and opened door slightly to let cool 15 mins. Took out and let cool on bench 15 mins.

    Reassembled and working. Still cannot believe it.

    Thank you so much, so happy I even gave $10 to help you keep this site up for others 👍👌

  11. Un énorme merci pour ce tutoriel qui pour ma part a fonctionné sur ma LG 42LX6500 3D.

    J’avais un problème de ports HDMI, ils reconnaissaient les sources branchées, mais aucune image sur la TV.
    Les autres connectiques (péritel, yuv, rca, optique etc…) n’étaient pas touchées par ce problème.

    Avant un changement de carte mère, opération de la dernière chance en suivant ce tutoriel, et miracle après 10min à 200°.

    MERCI

    ——————————————————————

    A huge thank you for this tutorial which for my part worked on my LG 42LX6500 3D.

    I had a problem with HDMI ports, they recognized the connected sources, but no picture on the TV.
    The other connectors (péritel, yuv, rca, optical etc …) were not affected by this problem.

    Before a change of motherboard, operation of the last chance following this tutorial, and miracle after 10min at 200 °.

    THANK YOU

  12. Another success story here with my LG 32LD550 that was only showing the red light that would blink when trying to turn it on. I baked it at 380 F for 10 minutes on parchment paper. Opened the oven to let it cool a little and then removed it and let it cool another couple minutes before testing it. I was amazed this worked!

  13. Just did this and it worked on an LG 55 in TV where HDMI ports stopped working. Did anyone do any special clean-up of the oven/kitchen after trying this?

  14. THIS FRIGGIN WORKS!!

    My LG 42LD560 had stopped recognising HDMI inputs.
    Actually it recognised they were there, but displayed the “No Signal” message.
    Baked the main board in my oven at about 200 °C for 10 minutes, then let cool for 30 minutes before removing from oven. Put it all back together and now it works perfectly!

    Thanks guys!

  15. I’ve been working with electronics for over 30 years, at first I did not believe it would work, I talked to a friend who makes the latest generation of SMD cards, I did not believe it either … but since the TV was Lost, I cooked my plate for 12 minutes at 220 degrees celcius and the TV was perfect! I learned two lessons with this story, the first one is that it is always worth the risk and the second one is NEVER TO BUY ANYTHING FROM LG !!! Thank you friends !!

  16. Still amazed to confirm that baking the board today fixed my LG 42LD550 TV! I first replaced the power supply but that didn’t help. With nothing to lose, I put the control board in a 375 toaster oven for 10 minutes and that did the trick! Thanks to all that confirmed the same on this page ; )

  17. Holy SH*T—This really did work!!! I ordered a Brand New Main Board which I’m sure I wont get for a while, but based on other reports of this fix lasting for a while and then going bad again, I decided I don’t want to BAKE the circuit board again and deal with the Smoke and Burnt Smell for a few hours which my dog did not appreciate..
    .( burning eyes- blah blah blah )
    I am amazed though, that it actually did fix my HDMI connections-But I hate when I have a screw or two left over:-(

    MY tv is an LG 47XL9500 Hi Def 3 D tv—hard to find a 3d tv these days!! My NEW board is costing about $220.00 shipping included, but its better than Spending $3000 and not to be able to see my md Movie collection!!
    My only hope is that when I wake up in the morning ( which is in about 2 hour) – because it took me all night to unscrew, shake & Bake, rescrew and test) I won’t realize it was just a dream and my TV is actually still broke 🙂
    Who knows…Maybe I will get lucky and this amazing fix will last a long time….

  18. My LG 42LE5400 (December 2010) turned on the other day and showed the dreaded “No Signal” from the three HDMI ports.
    RGB cables confirmed the picture would still work the old school way.
    So I did what everyone else here did… Trolled the internet looking for a fix and found this blog. Who knew!!!??? This site saved my bacon!
    I diagnosed the problem, found this site, removed and baked the board (15 minutes [including warmup] @ 390 degrees F), cooled and reinstalled in an hour and a half. Used a toaster oven out in the garage due to the smell.
    TV works great now!! I wouldn’t have believed it either if I hadn’t read so many other posts reporting their good luck. I figured what have I got to lose? None of my peripherals use anything else but HDMI.
    Thank you Zedic.com!!!

  19. LG 42LE8500 no sound, no picture, no backlight. They did not fix it even in an LG Authorized Service Center (main boards are not available). I baked it at 200 °C for 10 minutes. And… IT WORKS!
    Super Thanks! 😉

  20. Yeah, well, after 14 month of operation my LG 32LW570 ceased operation again with a purple screen for a moment and then displayed nothing but the flashing red power light. Repeated the baking procedure and its back into life. Lets see if it comes up again in another 14 months 😛

  21. Did not work for me..
    TV: LG 32LC46
    Issue: HDMI Ports failing and sending screechy audio after 5 mins a of being switched on didn’t seem to be coming from the speakers as the mute and volume buttons did not silence it. in time now showing no signal error on the HDMI ports. Scarts and AV cables were still working, audio working fine.

    ‘Baked’ in the oven for 10mins @ 190c as instructed.
    After taking out of the oven I noticed the scart slots plastic mould had melted as well as the optical audio output connector, I don’t use them so I wasn’t overly bothered.
    So.. on reinstalling the board after cooling sufficiently I plugged in the TV and the HDMI lead in to slot 1.. (from my Xbox) hdmi 1 was showing no signal.. plugged in to slot 2, this was working, including audio.
    After a couple of minutes, maybe 10 as I didn’t time it, the audio started sounding scratchy and continued but could be silenced by the mute button and controlled by the volume keys.

    So, my problem has half been fixed as the HDMI port 2 works and the audio is better but not fixed, but now I have no scarts or optical audio if I would have need it in the future..

    Did anyone else cone across this issue with the baking and melting the plastic bits?
    Also I found that some of the plastic ‘female’ connector parts were a bit more snug than they were before baking.

    I think I’m just gunna get a new main board I’ve seen on eBay for £15.. but thought I’d give this a go before, so for me nothing much lost.

    Thanks OP, but it did not work for me, sorry.

    1. I think your temperature was higher than set or you had hotspots in the oven. Maybe it was too close to the heating element?
      I’ve just baked my board at 200 C (stabilized during preheating, but with the board in it dropped below) for 13min and hadn’t experienced any plastic melting. The oven has a small vent that was working all the time, blowing the air below the center rack where I had the board seated. I think the vent helped distributing the heat in my case but I’m not sure if this ok in case of larger vents blowing directly on the board (like I’ve seen other ovens have).

  22. Just work for my LG 42LE5350.

    All 4 of my HDMI inputs stopped working. The main board is $290 so no way I was going to replace it. I baked for 10 minutes at 405 on my oven, 375 on a thermometer in the oven. The house smelled awful but my tv works again.

  23. Wow! Thank you! I can’t believe it worked!

    So my LG 42LD750 suddenly lost it’s HDMI connectivity. O all inputs was giving the dreaded no signal message. After a visit at a local TV repair shop that proved useless I eventually decided to try baking the motherboard.
    Removing the board was an easy process. All the connectors have a retention mechanism so don’t pull if it doesn’t get out easily.
    I used a small electric oven and an oven thermometer. After the temperature stabilized at 200 C, I’ve put the board in the middle rack on a piece of cardboard. Because the temperature dropped while I opened the oven door to insert the board, I decided to keep it inside for 13 minutes instead of 10. It released some nasty fumes that persisted for hours in the room after the baking was finished, so I regretted not taking the oven outside first.
    After 13 minutes have passed, I’ve let it in the oven to cool with just a small opening of the oven door. Haven’t touched it for 45 minutes or so. When it was cool I mounted it back in the TV and now everything is working properly. Now all HDMI connections are working. Yey! Let’s hope it hold.

    Supper useful and easy fix.

  24. I recently purchased a $7000 65″ LG Signature G7 OLED unit. Called LG Concierge for assistance with HDMI port failure on a rarely used 32″ display in my office. They couldn’t care less. Are there any attorneys interested in pursuing a class action lawsuit? Bad publicity may cause them to rethink their position. To pay $200 to repair a $300 television set is ridiculous. Although baking the board appears to work, end users shouldn’t have to be doing this. On principle, I will never again purchase an LG product.

  25. Hi!

    Add one more to the list. My 55LE8500 suddenly lost all HDMI inputs. Luckily I came across this site, and gave the baking method a go. Simple procedure..and worked wonders!! Let’s see how long the fix will last. Big thanks to Zedic!!

  26. Hi, just performed successful “cook” of my LG 47LE8500 board. Same symptoms
    “HDMI No Signal”, same resolution. Owen set @ 200ºC 12 min. Clean!
    Many thanks for the detailed explanation.

    Regards,
    Pedro

  27. Just wanted to say thanks again, I’ve just ‘baked’ my board for the 4th time in 3 years! I figure at some stage it will stop working but I’m glad you posted this fix!
    cheers
    Mark

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