You would try to obtain a service manual. That would have the points to measure and troubleshooting tree. I'm sure as a tech you've seen such manuals.
There are starting primers on Youtube from shopjimmy. I will supply a single example and you can find more.
https://www.google.com/search?q=shopjimmy+troubleshooting+a+black+screen+lcd+tv&source=lnms&tbm=vid&sa=X&ved=0ahUKEwjjo_b1srjVAhXqxFQKHeh8DSUQ_AUICygC&biw=1536&bih=731
Hi LG forum, this is my first post and I'm hoping somebody can help me please.
Watching TV last night and the screen went from perfect to a black screen, I still had sound. I tried to restart and unplug the unit a few times and still only sound and no picture apart from the odd dull flickering in the background.
Today I tried the TV, when I press the power button the red standby LED is very dull and is pulsing on of or intermittent.
Any advice would be great guys. I repair and build laptops and computers but I have no idea where to start with TV's. If I need to install a Tcon PCB or any other part I feel capable enough, if it's the panel I'm guessing it's going to cost more that the TV is now worth.
Is their anything I can check, ie ribbons, fuses ect.
Thanks in advance for any help.
Andi

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