Black screen on Sony 65x90ch (65x900h from Costco)

[Diah]

That test was on the other tv. That tv is working again. My last message was the forst tv where I found out the tv had the wrong main board in it. However when i swapped out the board and then did a firmware update to pair it, it still didn't show anything but a black screen. Then I tried to factory reset it and it didn't the turn of and turn on typical procedure. A few minutes layer it just completely turned off. The power board which was working fine up to that and had proper voltages is now dead. I'm curious if anyone has had experience where a main board has caused the power supply to suddenly fail after installing it.

show yours power boards socket and it print chart on it to know the pins name... also take it out and just plug it alone in wall socket measure any voltage you have on the socket which it before go to main boards.( this measurement should black probe on cold area chassis/GND and the red one on pins

[Adam Russ]

in which test you get switched to the right unplugged and got the display color test ?

That test was on the other tv. That tv is working again. My last message was the forst tv where I found out the tv had the wrong main board in it. However when i swapped out the board and then did a firmware update to pair it, it still didn't show anything but a black screen. Then I tried to factory reset it and it didn't the turn of and turn on typical procedure. A few minutes layer it just completely turned off. The power board which was working fine up to that and had proper voltages is now dead. I'm curious if anyone has had experience where a main board has caused the power supply to suddenly fail after installing it.

[Diah]

Well I got it working again. Took it all apart. tested the led with a backlight tester, all were good with proper voltage and brightness. Put it all back together. Upon first turning it on, just a black screen. Unplugged left side lvds cable, still a black screen. switched to the right unplugged and got the display color test. Hooked both up and all black. Did a factory reset and it started right up. I'm wondering if somehow one of the backlights was loose or making a bad connection triggering the 4 blinks. I has previously swapped every board with a working one from a good tv and no change so I figured it had to be backlight related with the 4 blinks and no board fixing anything. But since backlight tested okay maybe there was a bad connection somewhere. Anyway, glad it's working and I can get this one out of here. Thanks again. I'll be ordering the correct. board on the other tv and hopefully they'll be out of my room finally.

in which test you get switched to the right unplugged and got the display color test ?

[Adam Russ]

Second update. Tried to see if a factory reset would change anything. I left it on for about 5 mins to do it's thing and it suddenly shut off. Now the power supply is dead. Have you guy seen a new main board cause a power supply to go bad before?

[Adam Russ]

Just an update on that first tv that had the wrong main board. I got the new main board in and did the firmware update. Still a black screen. Not sure if it really worth investing much more time into it. Last thing would be buying a new t con even though when i swapped them in the past it didnt fix it. That could be due to the wrong board being installed though.

[Adam Russ]

Don't forget that potentially it means the LED circuit. Bad power board can cause it also. So yes do the due diligence on testing the LEDs and the rest. I've never actually had a Sony with bad backlights yet.

Well I got it working again. Took it all apart. tested the led with a backlight tester, all were good with proper voltage and brightness. Put it all back together. Upon first turning it on, just a black screen. Unplugged left side lvds cable, still a black screen. switched to the right unplugged and got the display color test. Hooked both up and all black. Did a factory reset and it started right up. I'm wondering if somehow one of the backlights was loose or making a bad connection triggering the 4 blinks. I has previously swapped every board with a working one from a good tv and no change so I figured it had to be backlight related with the 4 blinks and no board fixing anything. But since backlight tested okay maybe there was a bad connection somewhere. Anyway, glad it's working and I can get this one out of here. Thanks again. I'll be ordering the correct. board on the other tv and hopefully they'll be out of my room finally.

[EazyBone]

Don't forget that potentially it means the LED circuit. Bad power board can cause it also. So yes do the due diligence on testing the LEDs and the rest. I've never actually had a Sony with bad backlights yet.

[Adam Russ]

I have a 850e Sony that has a board for a 850f. The TV turns on still and once it gets to YouTube to play or something it crashes. The original owner said he replaced the board and it worked for a while and the same thing happened again. I also had this exact thing with a different TV, and I ordered the correct board to fix it. So you might have a wrong board in there.

BUT like we learn here, I also have a 65 Samsung that when I lookup the board it's listed as a 55 inch tv and ONLY for the 55 also.

Hopefully the version you need is cheaper.

They arent too bad. about 60 bucks on average. Hoping that'll resolve the issues. I'm halfway through checking these backlights on the 4 blink tv but so far the top half all checknout as working. can tell they made the zones smaller on this one (2 leds per zone instead of 3 on the H model). Im.hoping this one is easier to diagnose but I might need to double check it's boards are correct too. Thanks for the help before.

[EazyBone]

thanks. yeah I saw those. those are the correct ones. I'm not using the sticker number because it's for a J model, not an H model. I'm surprised this tv was working with the wrong board installed. obviously it doesn't anymore, but for a short time it did. I can't believe they put the wrong board in and sold it.

I have a 850e Sony that has a board for a 850f. The TV turns on still and once it gets to YouTube to play or something it crashes. The original owner said he replaced the board and it worked for a while and the same thing happened again. I also had this exact thing with a different TV, and I ordered the correct board to fix it. So you might have a wrong board in there.

BUT like we learn here, I also have a 65 Samsung that when I lookup the board it's listed as a 55 inch tv and ONLY for the 55 also.

Hopefully the version you need is cheaper.

[nomoresonys]

I can. Not long ago we spent a few hours trying to figure out why a vizio wouldn't work before we noticed the mainboard was completely wrong. It can be tricky, like when someone finds a tv or is given one without knowing if anything was done or tried. Some will buy a mainboard not knowing they have different ones for same models, it doesn't work so they get rid of tv, next guy assumes that the mainboard is original buys the same one and it just doesnt work.

[Adam Russ]

Those oughta work, they claim theyre new, if you want to make extra sure, just ask them if it will work with your panel number and give them the number or your sticker number on the mainboard, NOT the silkscreen number: https://www.ebay.com/sch/i.html?_fro...4255A&_sacat=0

thanks. yeah I saw those. those are the correct ones. I'm not using the sticker number because it's for a J model, not an H model. I'm surprised this tv was working with the wrong board installed. obviously it doesn't anymore, but for a short time it did. I can't believe they put the wrong board in and sold it.

[nomoresonys]

Its a sony see? go ahead and put sony 4 blinks in the search above, you'll get a ton of threads on it.

[Adam Russ]

Guess I'll be ordering the correct board and hope that fixes the issue. I'll have to check the tcon to make sure that's correct too.

Anyway, while you're here that other tv (65x90k) turn on, boots to the Google splash screen then turns off with 4 blinks. 4 blinks is most likely the backlights, right?

[nomoresonys]

Those oughta work, they claim theyre new, if you want to make extra sure, just ask them if it will work with your panel number and give them the number or your sticker on the mainboard, NOT the silkscreen number: https://www.ebay.com/sch/i.html?_fro...4255A&_sacat=0

[Adam Russ]

Type your board into shopjimmy.com they generally will tell you if there is substitutes or not.

Thanks. I did. They all list A5014266A whereas the existing one is A5031793A. I looked that up and it's a main board for a x91j or x91cj model. It's the next model year. This tv was purchased from liquidation.com/secondipity. Those people screw up so much.

[EazyBone]

Type your board into shopjimmy.com they generally will tell you if there is substitutes or not.

[Adam Russ]

The main was likely the issue in the first place. Now it's dead, probably not because of a jumper but because it's shit EMMC. Who knows, we would of likely ended up at new main board anyway, fixed everything on Sony's lol.

Yeah I did end up selling the old board. Kinds wish I didn't now. Looking for them, there are a couple of different main board numbers for thr 65x900h/65x90ch. Is there really a difference between 100689651 and 100689521? (A5031793A / A5014255A / A5014266A)

[nomoresonys]

Well I don't recall or forgot so I'll throw the question to Diah or someone who has verified it, no guessing allowed, does the optical led light up when the eMMC is bad?

[EazyBone]

The main was likely the issue in the first place. Now it's dead, probably not because of a jumper but because it's shit EMMC. Who knows, we would of likely ended up at new main board anyway, fixed everything on Sony's lol.

[Adam Russ]

Go ahead and check F 1000 and F 1001 on the green LDA board, make sure they have continuity.

Yeah both give me tone when tested