Trying to Save - SONY BRAVIA KD-75X780F - No Picture BUT there’s sound

[admxxx]

lotas

admxxx
No joy....

Tried covering both sides and no change in the screen whatsoever.
I could hear the OCD music playing and the TV was responsive to remote.
Just no visual sign of life on the Display.

Did you got 32v on the Vone ? Are both U-link on the COF boards connected properly (under the metal frame of the TV)?

[KYBOSH]

Did you got 32v on the Vone ? Are both U-link on the COF boards connected properly (under the metal frame of the TV)?

I never got 32v at Vone.
in my p previous post i mentioned i never got hardly any voltage at all.

im very sure the U-link films are connected properly as well.

[KYBOSH]

This this has been sitting/standing on my worktable for months now. I am ordering a new T-Con from Aliexpress today ($35). I need to start eliminating some unknowns!

[KYBOSH]

Got my t-con in today.
IIRC you cant just pop new components on Sony TVs but rather you need to install them and re-install the firmware.
Anyone know if that's the case with the t-con?

[Davi.p]

Sony needs a special pairing modality, unfortunately i took a note only on my dead tablet..

[KYBOSH]

Sony needs a special pairing modality, unfortunately i took a note only on my dead tablet..

I found the KD-75X780F service manual (not sure why I assumed it would be hard to find) and at first glance it doesn't specifically speak of any pairing procedure but it does give instructions on doing the firmware update which I have done before.

It also has a flow chart on how to proceed when you have a NO PICTURE situation.

Apparently the FFC cable is the first thing under suspicion and the panel/T-con is the last.
I never considered the cable...

Not sure if I can rule out the Mainboard even though I get sound and input responses with the remote control...

[Davi.p]

i do not remember this entire thread, i don't even know what's the result of the new tcon board, if it is no display (it seems so) i can't help you, i remember i disucussed this pairing task in an old forum now closed, and no notes on my cellular/PC , only the dead note on tablet, i think i would be happier if i would find a very simple app to sincronize the very few files that i use commonly, years ago i wrote a terrible script to do this but i did not work so well.. what i recall is that in that discussion i did not found in time the answer to help a.guy, the requester user gave the tv to a sony center that made a secret procedure and fixed the tv, i tried to rebuild what they do and i thought i found the answer, but if i remember something i tell you.. what i remember maybe is that they have a special usb mem key with a script inside, i about sure of the usb key.. the script forces the main software to update the main.settings.to the replacement tcon/panel, Sony tv checks every boot some data on the tcon eprom, also a model ascii string, it must match the one stored in MB, maybe doing a deep reset the tv reinitializes, need to enter service menu blindly and perform the reset. check the service manual, some very old lcd had a shortcut to the service reset with key combination..

[KYBOSH]

i do not remember this entire thread, i don't even know what's the result of the new tcon board, if it is no display (it seems so) i can't help you, i remember i disucussed this pairing task in an old forum now closed, and no notes on my cellular/PC , only the dead note on tablet, i think i would be happier if i would find a very simple app to sincronize the very few files that i use commonly, years ago i wrote a terrible script to do this but i did not work so well.. what i recall is that in that discussion i did not found in time the answer to help a.guy, the requester user gave the tv to a sony center that made a secret procedure and fixed the tv, i tried to rebuild what they do and i thought i found the answer, but if i remember something i tell you.. what i remember maybe is that they have a special usb mem key with a script inside, i about sure of the usb key.. the script forces the main software to update the main.settings.to the replacement tcon/panel, Sony tv checks every boot some data on the tcon eprom, also a model ascii string, it must match the one stored in MB, maybe doing a deep reset the tv reinitializes, need to enter service menu blindly and perform the reset. check the service manual, some very old lcd had a shortcut to the service reset with key combination..

I have not tried the new TCon yet as it just came in the mail.
Apparently it requires a pairing procedure but that may be a simple firmware reinstall with a USB stick.
This does not require the display to be on bcos the update occurs (without user interaction) as soon as the USB with the firmware is detected.

In the video there is talk of potential FFC misalignment issues which i will have a look at.

New FFC cables are pretty cheap from encompass.com ($20 for the pair + S&H).
I may order them in order to follow the troubleshooting steps.

[admxxx]

In my case I replaced the t-con and it was a direct swap, there was no need for any pairing or firmware update.

[Davi.p]

i know an update works but you have an already updated sw, so what you do? there is maybe a method to force an unwanted update..

[Diah]

sony android TV, even if the last update installed on it,,, put it on USB stick formatted FAT32 MBR mode an USB V.2 on the side, not at the back, TV take it out from wall socket... if it had joystick presst and pull it down, keep in this position and plug it back in wall... release the joystick only after the front LED change from white to green..

the TV will write back the firmware from eMMC/NAND section first and related to USB to register all other HW boards back include T-CON.. PUNKT