LG Monitor won't turn on - LG 34UM95 / 31MU97 FIX

A common issue that these LG monitor boards face is power outage management. The board in the video has suffered a sudden loss of power, such as a power outage or being unplugged without being turned off first, and refuses to spring on again.
The culprit to this problem is the IC205 EEPROM. It's stuck in a bad state and needs some help from us to reset itself in order to allow power back onto the board.
In this video I will outline how you can reset the EEPROM with just a multi-meter and fix your LG motherboard (LG 34um95p, 31MU97) in under 30 minutes and for less than $30.
This video is based on a thread by Integer13 and all credits go to his tutorial and the contributors in the comments below the post. This video aims to bring more awareness to the issue and make it easier for people to find a solution.
Link to thread in the pinned comment.
Hope this helps. Liking and commenting will help people who are also facing this issue find this solution, so please consider doing so! Thank you.
#LG34UM95 #FIX #31MU97 #LG

[@unsznuptryk]

For nearly two years, my LG UM95-P sat unused, and online all I could find was information suggesting that in such cases, it's best to replace the mainboard. Until today, when I finally stumbled upon your video, and now I can enjoy my monitor again. The first method worked for me. Thank you so much for sharing your knowledge.

[@nikolaiky2232]

everything works fine, but you don’t need a multimeter for this; just take any wire, connect it to a 2-3 K resistor and do the same. Thank you.

[@maxvandenhoven2320]

This worked perfectly for me! I really appreciate the video, as it is much easier to follow than the written blog post, even for someone with no experience in electronics. Thank you very much!

[@RayMcNemee]

Thanks for sharing this info Tom! This brought my LG 34UM95C back from the brink after an extremely nasty series of power fluctuations from a failing UPS. The 3rd option is what kicked it back to life. I immediately performed a factory reset, tested repeatedly, put the back cover on and then mounted it back on the desk arm. Working GREAT! 👍👍

[@pekkakoskinen-rg8po]

Thanks a lot. The instructions worked perfectly for my LG31MU97. The ship was located on the back side of the board.

[@Voiceof]

Hi, now my monitor is turning on, but just with the backlight. No display, not even menu, no sounds etc. Did anyone had similar situation?

[@Keale]

My 34UM95 doesnt have a rocker power switch and is powered on by the bottom facing button... Is there any way I can manage these fixes with this variation? Trying to hold that button down with my toe while I do it but being a toggle instead of a rocker I dont think it works the same.. 😢

[@rafalg2113]

Thank you so much! It worked on my LG 34UC87M-B! My board has completely different layout and I actually found IC205 EEPROM on the other side of the board. One of the methods #2 worked (can't tell which, I tried both). Initially after a couple of tries it started once, but then it wouldn't turn on again. I tried a couple of times over two hours, but it wouldn't work. I was just about to give up and order a new empty chip and a programmer (I found dumps on some forums), but I though to give it another try. Not only this worked, but this time the monitor turned on with white screen showing service information (serial number, board etc.) it wasn't there when it started the first time. Did a factory reset, turned it off unplugged it from a power supply, turned it on again after a while. I've repeated it a couple of times. It started each time. I was confident enough to assemble it together. It's works great since then and looks permanent (I hope so). That said I may order a new chip just in case. It's dirt cheap. I just need to polish my SMD soldering skills.

[@koodesignstudio]

Just AMAZING!!! I just fixed my 10 years old 34UM95-P with the first method (Black on P900 and Red on CS# and SCLK couple of times) and BING!! Thank you Million!!! 🤩

[@liljosh2002]

My monitor is gone lmao

[@jaimesrr]

Hi. Another one here (Spain) who just fixed one of them. It's from a friend. Thanks a million.

[@openwrtguru247]

It works for me.

[@mmslol123]

Perfect! I was looking for a comprehensive tutorial for ages.

[@ojoy2000]

The third option lit up my monitor. Thanks so much Tom. Appreciated for sharing the knowledge. A lot easier than other options like flashing the EEPROM.

[@AWTSupport-yb2kv]

Outstanding find! LG 34UC97 working.

[@ODgol4]

Dude, thank you so much. This brought my monitor back to life and I’m so thankful.

[@martinwaury8785]

Finally it worked for me with p900 and clk. But I had to put the positive (red) of the amperemeter to p900 and the negative (black) side to clk, not like you’ve shown in the video

[@imcalledandy]

Amazing tutorial. My board was different so thank you for sharing so many different methods. On the 31MU97Z - B you can’t really do method 1, so I opted for 2 and 3. I also realised that I was looking at the chip upside down. You need to look for the dot in the corner to find CS. Also listen to the sound of the chip. If it’s pulsing it isn’t fixed if it the tone becomes steady you should be good. Method 2 worked for me I believe (the 2nd one shown) as the third is also labelled 2 in the video. Thanks for helping me fix this monitor!

[@Flotzke1]

Great Video Tom, thank you very much!! Do more of this stuff. You saved me today ;) My 34UM95 is alive again.

[@Mall4567]

Thanks You very much for this guide . I save lot of money with repairing my LG 31MU97 ( SCLK & CS method version )