Chosen Solution

LG42LF580V Sound but no image. Did some research and most forums said it was the inverter board. Order one arrived this morning. Fitted board and same issue. Is there a solution or just get a new TV.? Update (09/14/2020) managed to upload a photo

@jteixeira your voltages look good. If your TV is on and you are at a channel that has sound, shine a flashlight at an angel against the screen. See if you can make out shapes silhouettes etc. LG has issues with bad backlight arrays that can cause problems like this. Also, the T-Con board can cause this once it has failed. Check for power on the fuse of that board. Let us know what voltage you get there. Also measure the voltage output from the power board to the backlight LEDs and let us know what you get on those.

You do not have to do the voltage checks since that is already done and those are correct.

If you do not have backlights and since you already changed the inverter the failure at this point would most likely be the backlight array (strips)

Hey @jteixeira I would test power at all the boards to see if something is not getting power. If you look at the wires plugged into the boards next to them will be a diagram letting you know what wire has what power?