LG 34GK950F defect analysis

The LG 34GK950F-B monitor I purchased in May 2019 has died. Its fate is the “horizontal lines” issue that many others have reported [1].

This is not what a $799 display should look like, but here we are.

lines

Onset

While using the display, it randomly made a buzzing sound as horizontal lines appears on the display - still usable albeit in a degraded state. A few seconds later, the entire display turned into the picture above - completely unusable. There was a loud buzzing sound from the lower right of the display throughout all of this.

Analysis

There were no signs of damaged components on the PCBs as I gradually disassembled the display. Only when I reached the panel did I notice something off - one of the ribbons connected to the panel looked different than the others.

The display is upside down in this picture. The pink arrow corresponds to the location where I initially heard the buzzing sound. outlier

The problem. char2

Under a microscope, I can clearly see that ribbon cable caught on fire at some point. char1

Outcome

I don’t know of a way to repair this. The ribbon cable is directly connected to the PCB and, seemingly, the LCD. A hot air reflow tool might help with the PCB, but I’m not certain it would with the LCD.

Honestly, I feel ripped off. $799 for a monitor only to have it break in less than two years of normal use. Worse, I’m concerned about the safety implication this poses to others suffering from the same problem.

Update

LG offered me free repair (including shipping) of the monitor after sending them a link to this blog post. I received my “repaired” display about a month after shipping it to them. While the display now worked, there was a noticeable hair stuck in the middle of the screen between the panel and glass.

hair defect

I contacted support yet again and was offered a second repair - also free of charge. Another month later and the “repaired” display is back in my hands… with two issues this time: a blue, stuck pixel and a black smudge.

blue spot defect
black smudge defect

I understand that LG is offering me free repairs on an out-of-warranty item, but they assured me that the service I received was no different than the service they charge money for. What the fuck…

My next interaction with LG support ultimately resulted in me sending the monitor to them in exchange for a $680 check - about $170 less than what I initially paid for the monitor in 2019.