Chosen Solution
My 60uj6050 lg tv’s screen got very dark one day. Tried all recommended settings,even factory reset the tv. Didn’t help. But then, a few hours later we turned it on, and it was fine. A few days later, the problem came back, this time for good. Here’s the information: no amount of fiddling with settings helpedScreen is dark, not black. No need for flashlightpicture is uniformly dim. No stripes, no halves, or spotsBought a power supply board and motherboard from shopjimmy. The parts that I got didn’t look like new parts. Neither fixed the problem. Before buying backllight strips as the next logical step, I have doubts. Based on what I understand, uniformly dark but not black screen is more likely to be caused by power supply. Could it be that shopjimmy sold me parts pulled from broken units, and the one I got was broken? Or does it sound like a clear case of burnt backlight? What do you make of the fact that picture briefly returned to normal before going bad again? The last question might point to the diagnosis.
Hi @minifixit , Uniformly dim is different to not being on at all so it may be a resistive connection (loose/corrosion?) somewhere. Check the connections/cable from the power board to the backlight LEDs first and then it may be at the LED strip connections. One way to find out maybe without dis-assembling the panel, is to purchase a TV LED backlight tester - examples only and check the brightness of the LEDs by disconnecting the LED power cable from the power board and connecting the tester to the LED power cable. As the LEDs will be powered by the tester and not by the power board this will help to point to where the problem lies, i.e. the LEDs or the power board (or possibly the mainboard if the power board is receiving an incorrect voltage level signal from the mainboard to dim the LEDs check the cable between the mainboard and the power board)
I’ve had several LG tvs that have had this problem and lost the 1st one because of not catching it in time but the problem is often due to my power cord. The cord provided with the tv must be cheap because After losing the 1st one all I had to do to the other ones is pick up a new cord at my local walmart and use it instead of the one provided. If you catch it early enough within a week of the problem initially occurring the problem will fix itself with a new cord. Plug the tv in with the new cord, if its bright enough to see the menu turn off energy saving and set picture to vivid and if it does fix itself it will do so within 1 to 2 hours depending if the charge diodes gets back to a proper charge. If it doesn’t then the diodes have been damaged due to lack of power and the entire power supply board will need replaced. I could fix my older tv if I had that power supply board but it was a limited 3D TV so the power supply board isn’t common enough to be found cheap.
