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Sound but no image. Have replaced inverter board but no joy

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

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Répondre à cette question J'ai le même problème

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Twofast2trac any advice on this.

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@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.

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

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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)

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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?

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@fasttrackpro thank you for you're reply. I have measured all pins with the TV in the off position and recorded 0 volts on all terminals. I have ordered a new multimeter to retest and to be sure as my current multimeter is old from when i was on the tools. Will update with progress. Is it possible that the readings are true and what does this mean?

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Test of the TV needs to be ON to get accurate voltage reading?

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Please see my finding below with the power on this time

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Twofast2trac Cannon upload the table i created can someone help

Top pin measurements with power on

OV 11.8V 11.8V 0V 24V 0V 3.4V 3.4V 3.4V

Bottom pin

0V 0V 11.8V 0V 24V 1V 3.4V 1V 2.9V

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On the board next to the pins is a print of the voltage layout. When you test the voltage of the pin layout it should match the print next to the pins.

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Jose Teixeira sera éternellement reconnaissant.
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