Sony KDL-65W855C mirrored, fading picture

[mrsith]

Hi, me again.

Grabbed that Sony with 6 blinking lights. Easy job, especially that I had LED set. Replaced them, upon reinstalling everything and doing test I was shocked. The picture is upside down and mirrored. There is some fading effect on one side (4th TV in a row with backlight problem that turned out to have this issue as well...), and there are 2 black vertical bars. Touching side and bottom tabs doesn't produce any change at all.
The LEDs were taken from kdl-x857c, basicay same model. I transferred screen to its chassis to save time, but just in case of any incompatibility I transferred main board, tcon and psu as well, so the only thing from 857c is the backlight and chassis.

Funny thing is, 857c from which I've taken leds, had similar issue - screen fading at one side and black bars. Screen wasn't mirrored though.

Any ideas or advices? Many thanks in advance.

https://streamable.com/zo8p54


My phone automatically rotated the photos. TV is standing upside down on the photos, just to be clear.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

are you sure the backlights are good, is that fadind/darkness in the middle there on those pictures? did you test them with a backlight tester? can get one for about 20 bucks on ebay or amazon if needed.

[mrsith]

Re: Sony KDL-65W855C mirrored, fading picture

That's definitely not backlight - all strips were tested with lab power supply and the backlight is spreaded evenly - its darkening/fading effect here. If you check the video, you can clearly see the slo-mo fading on one side of the screen (the one with black bars).

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

ok, I think its either a bad/loose tab bond or a shorted panel.

[mrsith]

Re: Sony KDL-65W855C mirrored, fading picture

Should I try cutting side tabs off?

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

well you need to be sure before hand, its not reversable, do the one ribbon cable at a time test, see what you get.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

ok, this one is from about 2015, much harder to work on because they did away with the sturdy bezels that were easy to get on and off, think they started using just glue/tape that might not even hold, can't remember if these even have the panels on both sides, if not then the side tab fix wont work.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

might give the "tape cutoff" method a try. If all your expected voltages are good, maybe check the components on the panel driver board/s for shorts or very low ohms.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

Have a sony xbr about the same year, damn thing don't even have a bezel, has a bad emmc chip I think, kind of amazing how these types even work BUT I still don't trust them to be reliable.

[mrsith]

Re: Sony KDL-65W855C mirrored, fading picture

Just played around with tape, no joy. One side is obviously bad, when that's the only side connected there are some stripes on the screen. The typical vertical stripes.
With only good side connected, the disconnected part is black instead of expected white, and the remaining half screen is still mirrored.

I'll check all the voltages and look for shorts, but honestly I think this one won't be possible to fix, as thee are 3 issues with it: fading/slomo effect, black fertical bars (present even when playing around with tape resulted in colorful artifacts) and the picture being mirrored.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

might be a lost cause, maybe tear it down very carefully, big screen easy to accidentally break, inspect the cofs closely see if any are burnt or discolored or much hotter than the rest, if you don't detect anything wrong on one side check the other side of the cofs, had one recently cof looked ok on outside the easy side to see but when I got the board to where I could see both sides, one was obviously burnt.

[nomoresonys]

Re: Sony KDL-65W855C mirrored, fading picture

ok, this one is from about 2015, much harder to work on because they did away with the sturdy bezels that were easy to get on and off, think they started using just glue/tape that might not even hold, can't remember if these even have the panels on both sides, if not then the side tab fix wont work.

only certain models are flimsy, just tore down a recent samsung, bezel was on very well, the heavy plastic framing was very sturdy, was even a bit of a pain getting it apart.

[mmartell]

Re: Sony KDL-65W855C mirrored, fading picture

If the tcon is the same between both models then swap the mainboard.

[mrsith]

Re: Sony KDL-65W855C mirrored, fading picture

I'll give it a try, but since the other TV had also slomo effect and black bars, I don't expect any difference