Sony KD 49X8307C

[Diah]

https://www.badcaps.net/forum/troubl...75#post3231475

[Donny2derby]

https://www.badcaps.net/forum/troubl...75#post3231475

Yes I have read that now again Diah. I don’t understand what you are trying to say! I’ve done that as you told me and still no 12v on T-con fuse.

Do you want me to utilise my bench power supply?

[Diah]

did the tv front LED indicator come on?

[Donny2derby]

Sort of mate. It does the same as before. LED indicator goes white for a few seconds then goes off.

[Diah]

Sort of mate. It does the same as before. LED indicator goes white for a few seconds then goes off.

my post try with replacement MB or do it yours self

[Donny2derby]

Those boards are £100 to buy Diah. Not economical to buy it and sell tv for profit.

Are we thinking this is now scrap tv?

[Diah]

[QUOTE=Donny2derby;n3232429]Those boards are £100 to buy Diah. Not economical to buy it and sell tv for profit.

Are we thinking this is now scrap tvno not now
take out the heat sink from the MB and upload photos on the boards from top and down side

[Donny2derby]

Ok will do that tomorrow.

[Donny2derby]

Ok Diah here are photos as you requested.

[Diah]

Okay.. read carefully please this time. yours Mainboards easy boards nothing complected at it this why.
1- the main firmware of this boards was Android 5.1.1 .. which the google service stopped working at it as well all apps include YouTube.
2- Sony didn't push.ed any upgrade from Android 5.1 to higher because this procedure of upgrade need internal file, not via air / internet.
3- Sony published on their web portal upgrade file in years 2021 to have this model and other similar to Android 7.1, which the user on his own risk did the upgrade and it take time more than 30 minutes.. if user plug the TV out from Wall , the Tv will stop working as i think yours now.

then what we will do ??
1- at yours POST 15 when you attempt Hard reset , the front LED Indicator changed from white to green.... this is good sign that the bootloader still in place and didn't eared during the upgrade.
2- download the zip file from Sony for yours Model... unzip it and copy the file ( never rename it ) just copy it on root of USB stick formated FAT32 not bigger than 4Gb..
2-A : if you formatted the stick with Windows 10/11 try to do it as standard, and labelof the stick write SONY
3- white the TV unplugged from the wall insert the USB stick at USB V.2 ( on the side ) not at USB Port V 3 ( blue one)
attempt the hard reset procedure and just release after it change to green... give time for it..... and you may repeat this several time... until the parts of boot and system written again.

at any point didn't plug it out from the wall,,,, only if you want to repeat the hard reset procedure.

[Donny2derby]

Diah thank you very much for taking the time for such a detailed explanation. However, whilst I know English not your first language, I am totally useless with computers and the language of them.

However all is not lost. My girlfriend is very good with this sort of stuff so I will ask her to try to understand what you say and we will attempt to follow this procedure. I will let you know if we think she can complete this task.

Thanks again for your time and patience.

Edit: Ok Diah I have spoken to girlfriend and unfortunately we have hit a brick wall. The computer she has from work has its USB ports locked down to prevent fraud etc. So we are unable to perform this procedure at home. I will have a word with some friends and family to see if we can borrow their laptop to help enable the process.

Girlfriend is confident with a non locked down laptop she can fulfill the tasks you advise.

[Diah]

i never wrote a roman, hard reset you did it before. and you know how..or where. Sony firmware to download and extract it.... formatting USB stick FAT32 any one can do it on PC.. then where are the difficulties make you hard to understand what i wrote before..

try use USB stick with LED indicator so you can notice when it blinking... id it does mean TV read the USB firmware. if my theory was wrong the TV didn't work because of wrong upgrade, then,there are BGA under the SOC. need to rework .

that's all for now over this forum.. stay healthy all.

[Donny2derby]

I have a bench power supply at work Diah. Shall I take pin 9 out of the plug and use the bench power supply to put 3.3v DC on it?

Sadly it looks like Diah has been driven away from the forum! lotas maybe you can help? Is it worthwhile me using a bench power supply like the one below to force 3.3v DC onto pin 9 on CN6401?

Would that force 12v onto T-CON?

Thanks.

[Donny2derby]

Is anyone else able to offer help on this telly? I don’t want to scrap it if it may be fixable. Is forcing 3.3v onto the pin mentioned a good idea? Or could I inject 12v straight onto the T-con fuse?

[Diah]

Sadly it looks like Diah has been driven away from the forum! ....Would that force 12v onto T-CON?

Thanks.

there are Naughty Kids over all... never mind..
don't use any external source... you did tested before the PSU are fine... its yours MB SOC the issue.. replace MB or rework first on SOC re soldering .

[Donny2derby]

there are Naughty Kids over all... never mind..
don't use any external source... you did tested before the PSU are fine... its yours MB SOC the issue.. replace MB or rework first on SOC re soldering .

Great to see you back buddy! I’ve sent some muscle round to the Italian stallions house to make sure he doesn’t give you any more grief!

Ive had a bit of trouble finding a FAT32 formatted USB that is no bigger than 4Gb but I eventually found on Amazon (site of the devil) and it arrives tomorrow so I will then try to do as you say and find zip file on Sony website!

[Diah]

Great to see you back buddy! I've sent some muscle round to the Italian stallions house to make sure he doesn't give you any more grief!

Ive had a bit of trouble finding a FAT32 formatted USB that is no bigger than 4Gb but I eventually found on Amazon (site of the devil) and it arrives tomorrow so I will then try to do as you say and find zip file on Sony website!

i don't think the issue with firmware... because when you attempted hard reset the front LED change from white to green.. this mean the most part of firmware boot loader are in place at the eMMC sector... boot loader when it start the Soc will switch on the BL and the 12V t-CON... which this didn't happened in your case... so it is 99.9% BGA under the Soc and this usual issue with MT Soc

put the MB on the 4 stand at straight position... and add load on the top of the chip ( any heavy metal to push the Chip down to boards and don't let it move ).... use hot air GUN 250 -300 degree for 15 second.. heat the chip from downside the boards ( let the hot air only focused on the CHIP area )... leave it cool and try it.

[Donny2derby]

What is 4 stand Diah?? I can take board to work tonight and use my rework station air gun to heat the chip up there. But I wouldn’t be able to try it immediately after.

I have looked online for MB and one site that sells them has them for £49.99 but currently out of stock. I have a notification set for a reminder when they are back in stock.

To be clear though, is this picture below of the chip I need to heat up?

Should I remove both heat sinks first?

Thanks as always for your help.

[Donny2derby]

Out of interest Diah, what would happen if I used an external source to put 12v DC directly onto T-CON fuse F1?

[Diah]

Out of interest Diah, what would happen if I used an external source to put 12v DC directly onto T-CON fuse F1?

heat sink should removed to apply heat from the Top, but i do recommend the heat to be from downside..and we add heavy load on the top of the Soc.
standing... mean legs or any others ells the main boards wil sitting on it and you have access to the downside of the boards to start heating under the soc. .

for yours other question, its dummy things when user use external source to do any test, because the set PSU are the best source, and you do it by using 3.3V standby to switch on VCC REG12 and T-CON 12. so this step are over.. now we need to make the set switch this both include BL on his own. and the mainboards who are responsible for this action.