Sony XBR-75X940E intermittent 6 blinks error code

[Davi.p]

I donl not believe what i'm reading, this tech guy is a thief or incapable for me.. do not trust him much, ask him clearly if he registered the same behaviour of your whole tv, then you can start changing the board..

[Davi.p]

I do not believe what i'm reading, this tech guy is a thief or incapable for me.. do not trust him much, ask him clearly if he registered some behaviour like your whole tv, then you can start changing the board.. tell me which one is the board he claims is the culprit..

this case reminds me one big tv 65" from Panasonic i have fixed two years ago, the previous owner said it sometimes do not power on and flashes the spy led, then usually turned on after some attempts , one day suddenly turned off with led error code and did not turned on any more.. i taken it for free and repaired two damages on the power board, there was a shorted micro cap and a bad little smd power mosfet, after about 4-5 usages it showed the damn bad news of a failing edge backlight led strip... in conclusion i can trust that one of your power boards is defective (possible cause mains spike) and is probably the one attached to the led board (your last photo), but it really worth the board change.. your backlight system is more stable i think and do not have problems.. and a good tech can spot the fault on the board, yours is not a very good tech.. for me..

[tiki66]

I have removed the 3rd pin on the connector between the G75 and the main board on the G75 side. I attached it to a screw hole.

Not sure which one is the LD Board.

Thanks!

Ground that pin again. LD Board is the one in the middle with metal plate over it. It should have a green and a red diode on it. If it lights green, LEDs are ok, if it light red, one or more segments are bad.

Do the thing I also said:


Anyway, try grounding BL_ERR and it could solve your problems. It is pin #27 on CN1001 on LD board that you have to ground (that small flat cable that goes from MB to LD board)

That way you should "kill" both 4x error and 6x error. If the tv sometime starts without backlight, then it's a problem with power supply that feeds power to LD board.

[nomoresonys]

I would not be surprised if it was a bad/marginal capacitor. He did say they were weak correct?

[GoodCapDude]

I would not be surprised if it was a bad/marginal capacitor. He did say they were weak correct?

Yes but for some reason he did not try to change them. He doesn't speak French very well and communications were sketchy.

[GoodCapDude]

Ground that pin again. LD Board is the one in the middle with metal plate over it. It should have a green and a red diode on it. If it lights green, LEDs are ok, if it light red, one or more segments are bad.

Do the thing I also said:


Anyway, try grounding BL_ERR and it could solve your problems. It is pin #27 on CN1001 on LD board that you have to ground (that small flat cable that goes from MB to LD board)

That way you should "kill" both 4x error and 6x error. If the tv sometime starts without backlight, then it's a problem with power supply that feeds power to LD board.

I do not see the green and red led. I think that's because I haven't removed the metal plate. Although I think I have had the impression to see a red light at some point when it went wrong. I do my tests in the dark so I can tell if the backlight is on or not through very small openings. The tv installer 8 years ago did not leave the stand of the TV. So It is quite difficult to handle efficiently for tests.

Anyway, I do keep in mind what you suggested and will definitely try that before I'm trough with the TV. Last time I unpinned the other pin on the other connector, I wasn't too comfortable with putting it back. I'm gonna wait a little bit before trying again. Also, I understood it was not between MB and LD board but between G6 board (part of the psu) and LD board. Between LD board and MB, it is a ribbon, there is no "pin" i can remove.

Thanks for your comments.

[GoodCapDude]

I do not believe what i'm reading, this tech guy is a thief or incapable for me.. do not trust him much, ask him clearly if he registered some behaviour like your whole tv, then you can start changing the board.. tell me which one is the board he claims is the culprit..

this case reminds me one big tv 65" from Panasonic i have fixed two years ago, the previous owner said it sometimes do not power on and flashes the spy led, then usually turned on after some attempts , one day suddenly turned off with led error code and did not turned on any more.. i taken it for free and repaired two damages on the power board, there was a shorted micro cap and a bad little smd power mosfet, after about 4-5 usages it showed the damn bad news of a failing edge backlight led strip... in conclusion i can trust that one of your power boards is defective (possible cause mains spike) and is probably the one attached to the led board (your last photo), but it really worth the board change.. your backlight system is more stable i think and do not have problems.. and a good tech can spot the fault on the board, yours is not a very good tech.. for me..

As I said, the communications were difficult. It is hard to know what he really came up with. What he was sure about and what remained unclear. He said the G75 board was the culprit. He said circuits were interrupted around the pics he sent me (see my previous post: the back of the board and then a close-up). It seemed strange as an interruption would not allow the TV to work "sometimes"... This tech guy is well established but I have to agree that what he told me did not inspire confidence.

Your panasonic example feels like something quite similar to my case indeed. Thanks for sharing your thoughts.

[GoodCapDude]

So the situation has changed a bit. For the worse. Since I have disconnected and reconnected the 16 ribbons of the LD board and the ribbon between the LD board and the MB (BMKP), I haven't been able to obtain a clean startup. I have succeeded after getting the boards back from the shop so the worsening seems rather link to my tinkering with the ribbons. Although I can't be sure. And maybe I'm gonna be able to start the TV again at some point.

Anyway, at this point it does not start anymore. I turn it on, the white light goes on, I hear a clack and can see that the backlight seems on. Then the white light goes off and there is a second "clack" and the red light starts flashing 6 times and the backlight goes off (the little I can see of it through little holes). This all happens quite quickly but does not seem absolutely consistent to me. Sometimes some phases last a little longer. Sometimes I can relaunch a startup sequence once the red blinking has started using the power button. Sometimes I can't.

Here is where it stands this evening. I gotta go... I'm considering trying another tech although if the TV never starts now, maybe it is becoming too complicated. Anyway. Thanks to those who have followed this story until now!

[GoodCapDude]

Yeah no. Sorry. I just had a clean start before going to dinner. Maybe they are just a bit less easy to obtain than before.

[Davi.p]

Hi, first, it would be useful if you will test all the CN6404 when it does an when it doesn't the defect, so we can establish: A. if it is missing the Reg-12v from G75, B. if problem is LD board or leds.
more than this, i wish a very.close up bright photo of the chip the technician showed you in photo , because i suspect it is counterwise, maybe he resoldered , it is also a bit misaligned

[tiki66]

I do not see the green and red led. I think that's because I haven't removed the metal plate

How do you expect to fix something if you don't dissasemble it?!? I'm out of this thread, this makes no sense

[GoodCapDude]

How do you expect to fix something if you don't dissasemble it?!? I'm out of this thread, this makes no sense

Well I'm way over my head with this thing. I'm looking for a low hanging fruit that could have been fixed and I'm not willing to take it all apart. I don't have the space nor the skills. Now you're right, I could remove the metal plate even though I first decided it was outside the scope of my investigations. Anyway, sorry for being a bit sketchy and thanks for your help anyway. You may well have the last word when I try to ground BL_ERR. Even if you're not there anymore.

I'm not someone skilled doing a comprehensive diagnostic/repair.

[GoodCapDude]

Hi, first, it would be useful if you will test all the CN6404 when it does an when it doesn't the defect, so we can establish: A. if it is missing the Reg-12v from G75, B. if problem is LD board or leds.
more than this, i wish a very.close up bright photo of the chip the technician showed you in photo , because i suspect it is counterwise, maybe he resoldered , it is also a bit misaligned

Ok. I will provide the pic and for the test, I would need a multimeter, right? I don't have one. I understand it can be frustrating to try to help a guy who does not know much.

[Davi.p]

You will never go somewhere with a screwdriver only, this is way too obvious.. try get one, hope you choose one cheap from Bside/aneng/zotec, they're the same product, perfect for home use