lg 60ln5400 power on to lg logo and stuck at a weird screen

[Jp06]

Happy holidays everyone,
I have a lg tv (60ln5400) stuck screen issue and hoping that someone could tell me what it is and how to fix it.
I lost the power cord and remote so i got a replacement cord on amazon. When i plugged it in, the tv came on without having to press the power button. The lg logo appeared and went straight to this screen with the circle at the bottom right and it's stuck there (refer to images please). There are no responses with any buttons from the back of tv.
I baked the main board at 385F for 10min and have the same results.
Thank you so much for any helps.

[nomoresonys]

Could be a bad eeprom, that's one of the symptoms.

[nomoresonys]

Ic 104, try heating it with a hairdryer or cooling with freeze spray or upside down can of duster, then plug in tv and try it, see if there's any change, even if only for a while.

[Jp06]

Thanks, I will try that out tonight. I had a feeling that i might need to buy a new main board.

[nomoresonys]

Replacement mainboard is probably the best bet, specially if fault can't be pinpointed.

[nomoresonys]

Took a look around the net, most say sold out, best I see is there for 110 bux, there is a make offer option also: https://www.ebay.com/itm/LG-60LN5400....c100290.m3507

[nicholas1110]

From the picture it appears that it is trying to lower the volume as you can see the - symbol is highlighted red. I suggest unplugging the buttons and see if the fault goes away.

[Jp06]

I did what Nomoresonys and Nicholas suggested and got no changes. What seems odd is why does it power up right away when I plugged the power in (without having to press the power button). Can a bad ic104 or main board causes that or is it short circuit somewhere?

[nomoresonys]

Yes bad eeprom can do that.

[Jp06]

Thanks Nomoresony, I will get a new replacement board.

[mmartell]

Originally Posted by Jp06

I did what Nomoresonys and Nicholas suggested and got no changes. What seems odd is why does it power up right away when I plugged the power in (without having to press the power button). Can a bad ic104 or main board causes that or is it short circuit somewhere?

Most times the main board remembers the state it was in when power was removed. IOW if you could power it off with the remote then unplug the power upon plugging it back in it would return to standby instead of "on". Try it with another TV you have.

[Unspun01]

Originally Posted by nicholas1110

From the picture it appears that it is trying to lower the volume as you can see the - symbol is highlighted red. I suggest unplugging the buttons and see if the fault goes away.

I agree.

Volume down button is highlighted in red. It appears the button is pressed, or some wire is pinched/shorted and makes the TV think the button is pressed.

Did you disconnect the buttons from the wire harness only? or did you disconnect the wire harness from the mainboard. If it is a bad wire, try disconnecting the harness from the mainboard.

Could also be a bad de-coupling capacitor or pull-up/pull-down resistor on the volume down input line to the processor. If you can figure out which line is being pulled down, you may be able to force it the other way.

You could also try shorting pins 5-6 on the 8-leg SOIC EEPROM/SPIFlash chip when you plug in the TV. This will interrupt communication to and from the EEPROM IC and could allow you to start the TV.

[nomoresonys]

For sure shorting pins 5-6 might work, don't cost anything to try.