Sony 85x90CK 4 red blink

[EazyBone]

So I got this Sony and purchased it working.. got it home and it was 4 blinks red. Seller actually refunded me thankfully. Now it's massive to take apart and I know 4 blink can be the panel sometimes but not always..

But I found a method through other ways with grounding out the bl error pin on the LD driver board. Now the tv turns on and works.

Pin is number 27. It was either remove the resistor right next to the solder pad or solder the pad to ground. I soldered the pad.

Now what is this going to do to the tv? Is it just going to die shortly down the road? Would it be ethical to sell this? Anyone have a clue.

[nomoresonys]

No, I wouldn't resell it, not really even sure if it's going to be safe to operate being that the bypass is eliminating a safety feature. Most of the time when the ground-out bypass works, it's bad backlights or backlight circuit. But I've also read and suspect that the protection circuits are way too sensitive in a lot of sonys.

[EazyBone]

So it at least helped me to know that the backlights are out. The TV now stays on longer then 15-20 seconds now. And because I couldn't really test the LEDs without taking it apart and .. let's face it this things 85 inches and expensive LEDs .

So turned on screen test and can see visable black spot where LED or LEDs are out. Looks like I need some new leds to fix it.

I'm sure someone who doesn't need to replace the LEDs can get some more life out of it doing what I did for personal use but I can't sell this until it's fixed now that I know the definite issue.

Good tool to diagnose though.

Agree Sony, I thought about it after I posted, can't sell it. I'm sure it'd be fine to burn out like normal but who knows .

Sometimes I just got to post here and then I figure it out 😜

[nomoresonys]

I tore down a xbr65x900c to the backlights to check them, NEVER again for that model. Was a complete nightmare about a million screws and many were very small and just refused to come out without stripping. Plus the tv is basically shit, is edgelit so the picture quality was never good anyway.

[nomoresonys]

Here's Nick's doing one, he makes it look easy but it's definitely a tough nut to crack: https://www.youtube.com/watch?v=S5V0hRjH7TA

[CapLeaker]

Interesting… hoping for more nice pics!

[nomoresonys]

I hear that CapLeaker, those are two great colors there.

[howardc64]

This review claims 54 dimming zones. Can't find any details on SONY website. Can't seem to find LED strips for these.

https://www.rtings.com/tv/reviews/sony/x90k-x90ck

I've taken apart an XBR-65X900F with 2 dimensional dimming zones. LED strips require much more complex flex attachment to be able to control the 2D dimming zones. Here is shopjimmy's backlight pictures ( link ). You can see a flex connector for each of the 10 row LED bars to be able to control individual LEDs on each row independently. Here is a video of the 65X900F backlight system

https://www.youtube.com/watch?v=fPvSwhDRoHA

Here is a picture of the 65X900E backlight system. Looks slightly simpler than 900F. Probably less dimming zones.

https://www.youtube.com/watch?v=mofOjGM9SOk

Your test seems to show 2D dimming zones so likely similar to above setup. Complexity will be related to the # of dimming zones.

[tiki66]

Now what is this going to do to the tv? Is it just going to die shortly down the road? Would it be ethical to sell this? Anyone have a clue.

How much working hours does it have?

It's a FALD tv so normal rule "if one LED failed, probably other ones will fail soon too" isn't correct. Since it dims, turns on and off different segments regarding to picture on tv, other leds are probably fine. This segment could have died just because one LED was fault. Or because it was at 100% backlight all the time and at that part of the screen there was something that needed to be bright. Or maybe it was demo set and was working 12 hours a day on vivid mode again with 100% backlight.

Sony uses high quality parts, so there is small chance for another failure. At least not so soon. That's just my opinion.

I've grounded alot of BL_ERR like that and it's been a few years and people still don't complain. Heck, even I use one KD-65XG9505 like that.

I wouldn't call it a safety feature either since LD board turns on/off each segmets invidually, so LEDs are not connected in series and there is no voltage or current rising on other LEDs.

I'd continue to use it like that, it could last for years, and that is too big of a screen to risk breaking it

[EazyBone]

Yea I found the leds for this TV and ordered them already. Thx for all that extra info. I think if I would of given the tv to a neighbor I would of left it but I just ordered a strip of LEDs instead. It's nice to know about this trick though. If I don't break the screen I'll post back. This is the one where the screen is attached to the bezel, I prefer to take off the frame and screen together rather then dealing with all the crap that's made after you cut through the tape.

[nomoresonys]

Well Budm is the one that said it was bypassing protections, so I'll take his word for it. Good luck to anyone who only changes one led and hopes that no more will fail, they are all leds and DO have the same amount of time and wear on them. Fact is they wear out over time, it's that simple. Unless you are the buyer for sony parts...then you don't know what parts they are using. Sony being a great quality tv is based on past reputation and isn't true today, very similar to what's going on with samsung. I guess next someone will be saying that samsung uses high quality parts.

[nomoresonys]

As long as we're just tossing out opinions. Here's what I think happened. Sony and samsung WERE making quality tvs...then a number of years ago competition got heavy and prices started to plummet, so to compensate they both started cutting corners and before long their quality was just as bad as the cheap competition, which brings us to today. Why they did it? Out of greed no doubt and maybe they thought they needed to to keep a profit margin since tvs got silly cheap to buy.

[nomoresonys]

Those that have paid attention can see the correlation of the price drop and the rapid increase of problems with those trusted name brands.

[tiki66]

Yea I found the leds for this TV and ordered them already. Thx for all that extra info. I think if I would of given the tv to a neighbor I would of left it but I just ordered a strip of LEDs instead. It's nice to know about this trick though. If I don't break the screen I'll post back. This is the one where the screen is attached to the bezel, I prefer to take off the frame and screen together rather then dealing with all the crap that's made after you cut through the tape.

LCD is meant to be dissasembled with bezel so it's a right thing to do. Good luck!

[CapLeaker]

Well Budm is the one that said it was bypassing protections, so I'll take his word for it. Good luck to anyone who only changes one led and hopes that no more will fail, they are all leds and DO have the same amount of time and wear on them. Fact is they wear out over time, it's that simple. Unless you are the buyer for sony parts...then you don't know what parts they are using. Sony being a great quality tv is based on past reputation and isn't true today, very similar to what's going on with samsung. I guess next someone will be saying that samsung uses high quality parts.

Bypassing protection is only something for the more advanced folks here. Other than that I don’t recommend it at all. I do bypass protection circuits all the time too. BUT: One has to know what they are doing too.

As far as Samsung vs Sony, I have both and work awesome! My Sony made once a physical buzzing and zapping noise from inside the TV during a heavy thunderstorm, then it shut off. I turned it back on afterwards and did a black screen. Unplugged it, wait for 10 mins, plug it back in and it is still going like a champ as nothing had happened. I was close to opening the TV up, but never did. I still rock an old B series a K and MU series Samsung TV’s. I still got that big TCL that had that bad main board.

[nomoresonys]

Have old sharp and sony ccfl tvs pre 2010 never a problem with them, 2 lg led units around 2012 only one minor problem. Those earlier name brands were over-built, later they started with the corner cutting. I wouldn't buy a new tv. would try to fix a free one of course BUT wouldn't invest a lot, just don't trust anything after about 2016. Always hated the clunky apps, I think they are crappy even in the new tvs. I prefer a dumb tv with a roku type add-on device.

[nomoresonys]

I think sony is better than samsung but they have emmc issues, samsung can't seem to install a decent panel.