LG 65ET961HOZA, no video/no audio, black screen

[Damirget]

Hi,

I am new here, so first off all I would like to thank you all for advice that you share.

i did saw few similar problem as mine on this forum, so lets see if I will be able to bring my TV back to life.

When I power TV, I could here relay click and red light blinks for 7 times and then it stops lit, looks like TV is ON, but nothing on a screen, no video, no backlight and no red light on Optical connector on MB (when T-Con board is disconnected, red light blink for 3 times and then is ON, same as TV is off and relay clicks).

On power supply connector P201, I have all voltages (3.3, 12, 20V), but DRV-ON is showing 0.003V on standby and it goes up to 0.3v when Power button is pressed. There is no voltage at all on connector P251 (which is connected to T-con board)…there should be 22VD, 12VT. I checked all fuses on T-con board and everything looks good….there is no changes in DRV-ON state with T-con board connected, or disconnected.

There is no any visible signal LED lit on a Main Board.

is it possible that with all cables connected, I try to short PWR-ON i DRV-ON, so I bring 3.3V to DRV-ON to check if that will turn on 12, 22V for T-con board?

any other suggestions?

thanks,

Kind regards,
Damir

[EazyBone]

Try disconnecting one cable at a time from MB to tcon. And try turn on. And then try one cable from tcon to panel one at a time and see if it will turn on.
I don't see tcon picture, but with everything plugged in any voltage on the tcon fuse on both sides?

[Damirget]

Hi,

i tried disconnecting every cable one by one, but still I do not have proper voltage on DRV-ON.

When I disconnect P7601 connector from MB to T-con, then I do not have any voltage on DRV-ON, regardless of the status - standby or power on.

I bypass PWR-ON and DRV-ON and I got 22VDC on power supply board for T-con, but only when P7601 cable is disconnected, otherwise even with bypassed PWR-ON and DRV-ON, I have 0V.

With all cables connected to T-con board (except P7601 - one of the cables for MB) i do have 22V on a fuses (marked as green on attached picture, but I do not have on fuses market with red).

I still do not have backlight on screen, I think that is because I am missing 12V.

any ideas?

thanks

[EazyBone]

You'll never have a backlight, this is a oled

[Damirget]

Yes, you are right…..but anyway I am still
missing 12V to T-con and I still don't have any light on MB even with bridged PWR-ON DRV-ON.

ideas?

[EazyBone]

Where has diah gone? Forum change and he disappears. He loves his OLED threads.

I had something similar on a 55CX OLED. Same manifestations I think, this new forum doesn't let me search properly but I ended up changing the main board/tcon together (was cheaper to get both from same broken tv) and it fixed the problem for me.

Trying to find it

[Damirget]

I am trying to source same board for my TV, but no luck…I do assume that issue is on a main board, as it doesn't send DRV-ON, even with disconnected T-con…

lets hope Diah will see this post, so maybe he has some advice.

Thank you

[Damirget]

Does anyone have schematic diagram for Main Board 65” OLED LG TV?

I managed to trace DRV-ON signal from P7603 connector (cable connection between Power supply - Main board), to resistor R322. I found that resistor shorted/bypassed. From that resistor line is going to IC101.

Resistor next to R322, R319 is also shorted/bypassed….that line is going to IC101 as well.

Is that normal that resistor is bypassed? Is that resistor in that line for monitoring “open loop”?

I am just guessing, but some schematics would definitely help

[Damirget]

I have disconnected Main board, and connect 3.5V to PWR-ON, DRV-ON and 12V-ON, with all cables connected (everything except MB…LVDS cables disconnected as well), I have black screen.

if I disconnect first or last panel ribbon cable from T-con board, I can see some lines on screen.

Does that mean that my panel is defective? Could that be an issue with T-con board?

Thanks

[EazyBone]

Ever since this forum changed I feel like people left.

That doesn't look good to me (not professional at this though) I have had similar reactions to different OLED with panel short. Wish diah could answer lol he's like OLED guru

[Diah]

thanks EazyBone for yours comments..., its really because the new style and color hurt my eyes allot so i avoid coming over here..
Damirget put all cable in place as it should only disconnect the socket EVDD on the t-con side.. then turn on... check if the optic on MB come on (llit Red)
if yes..... panel issue
if no... need more test on T-CON driver boards

[Damirget]

Thanks Diah for reply!

i tried with all cables connected, only EVDD cable disconnected and no light on MB optic

[Diah]

Thanks Diah for reply!

i tried with all cables connected, only EVDD cable disconnected and no light on MB optic

at yours post 3 its sound to me you did test the power boards and T-con and panel as stand alone.... but its not clear to me what you did exact.
to have correct test..
1- MB disconnected from PSU
2-MB LVDS disconnected from T-con driver boards-- all the reset cable should be in place

3- we jumper STBY to Power on... same time we jumper STBY to T-con on--- and drv on...... so the T-con should have 12V and EVDD volts too
check the screen how it look

[Damirget]

Yes, I done exactly what you wrote.

After I put jumpers in place, PWR-ON and DRV-ON to 3.5V I have 22V for T-Con, but I dont get 12VT-ON.

If I apply also jumper (3.5V) to 12VT-ON then I get all voltages for T-con, including 12V.

With all 4 ribbon cables connected from panel to T-con board I have black screen, if I disconnect one/two panel ribbon flat cables I do get some lines on a screen. Please see pictures in a post #9

Thanks

[Diah]

Yes, I done exactly what you wrote.

After I put jumpers in place, PWR-ON and DRV-ON to 3.5V I have 22V for T-Con, but I dont get 12VT-ON.

If I apply also jumper (3.5V) to 12VT-ON then I get all voltages for T-con, including 12V.

With all 4 ribbon cables connected from panel to T-con board I have black screen, if I disconnect one/two panel ribbon flat cables I do get some lines on a screen. Please see pictures in a post #9

Thanks

did you in yours life saw picture on this TV ???😎

[Damirget]

Hahahaha…..unfortunately, yes I did saw picture on that TV!

[Diah]

i am talking on this TV not on That..LOL

[Diah]

end rsult from what you testing and wrote for me at least panel could... could be fine but t-con driver boards defect.... MB defect too. sorry i done have good news

[Damirget]

Thanks Diah for your time….no worries!

I will try to heat up the MB, just to see if that would help!

can you please tell me one thing, even if MB is locked/sleep I should still got red light on Optic with disconnected T-con if MB is good?

And with disconnected MB, with bypassed PWR-ON, DRV-ON and 12V-ON, I should see color pattern on screen?

[Diah]

Thanks Diah for your time….no worries!

I will try to heat up the MB, just to see if that would help!

can you please tell me one thing, even if MB is locked/sleep I should still got red light on Optic with disconnected T-con if MB is good?

And with disconnected MB, with bypassed PWR-ON, DRV-ON and 12V-ON, I should see color pattern on screen?

no need to play with MB.... if you have working T-CON driver boards and the last test we talked on done and there color pastern (R.G.B ( showed on screen....... then you can repair the MB... nit with blind eyes to heat it.
MB working and sync with T-con driver boards... any wrong at the panel or the t-con... MB will be great SOS signal to turn off the PSU ( second relay click ypu hear ).... if we force this SOS there will be fire real fire..... so ask yours self if you are under insurance and no kids at home,