Sony KD49X8005C Assistance Required Please.

[Stevie406]

Hi Guys, This is my first post. I am pretty new to TV repairs, I have intermediate Knowledge with electronics,
and wish to further my knowledge in all aspects of electronics repairs.
I have a few LED TV's to repair, I am currently working on the following unit.

Sony Model KD49X8005C
SMPS Board <> 1-980-310-11
Main Board <> 1-894-595-12
White Sticker Sony (GL6) APS-395 4-574-565-01
White Sticker APS-395(CH) 147463311-1511M000532

When plugged in, the standby light is white for around 10 seconds, then fades to nothing.
There are no signs of life on the screen, just a black screen.
There is no sound from speakers.
The optical output on the main board turns red for around 8 seconds.
I have taken the following readings from the SMPS, and a few from the MAIN Logic board.
I would appreciate if someone could please point me in the right direction, as to what voltages I should be getting,
or where I should try testing next.
I can supply any pictures needed to assist further.

No Sound
No Backlight (unless tested with LED Tester),
Tried Hard Reset, Got Green Indicator light, No Difference.
Tried Firmware update. No Difference.

Any assistance in trying to fix this unit or advice on what my next step would be will be very much appreciated.

Regards
Stevie

Connector CN6401
2- DC-Dimmer--------- 0.0v_______1- NC------------------- NC
4- PWM-Dimmer------- 0.0v_______3- BL-ON--------------- 0.0v Pin 7
6- Blinking------------- 0.0v_______5- STBY-3.3v----------- 3.49v
8- BL-ERR-------------- 2.386v_____7- AC-OFF-DET--------- 3.49v pin 3
10- GND--------------- GND_______9- Power-ON------------ 3.481v
12- GND--------------- GND_______11- GND---------------- GND
14- REG 12v----------- 12.87v_____13- REG-12v----------- 12.87v
16- REG 12v----------- 12.87v_____15- REG-12v----------- 12.87v
18- REG 12v----------- 12.87v_____17- REG-12v----------- 12.87v
20- GND--------------- GND_______19- GND---------------- GND
22- GND--------------- GND_______21- GND---------------- GND
24- T-Con-ON--------- 0.0v_______23- GND---------------- GND
26- T-C0n-VCC-12v--- 0.0v_______25- T-Con-VCC-12v---- 0.0v
28- T-Con-VCC-12v--- 0.0v_______27- T-Con-VCC-12v---- 0.0v

Connector CN6801
+ LED = 95.46v Ground to Chassis
- LED = 14.98v Ground to Chassis

Backlights were tested via LED Backlight tester connected to unplugged CN6801 at 96V, All bulbs seem to light correctly.

Here are some of the voltages I measured from the SMPS Board.

SMPS Board__________SMPS Board_________SMPS Board
(Chassis GND)________(Chassis GND)_______(Chassis GND)
D6201 = 3.493v_______R6806 = 0.0v_______C6408 = 12.67v
D6202 = 3.493v_______R6807 = 12.87v_____C6409 = 12.67v
D6401 = 12.87v_______R6420 = 12.87v
D6402 = 12.87v_______R6421 = 12.97v
D6801 = 95.50v_______R6419 = 0.0v
D6802 = 95.50v_______R6410 = 12.87v
D6803 = 95.50v_______R6804 = 95.40v
D6804 = 95.50v_______R6809 = 0.0v
D6805 = 95.40v_______R6207 = 3.491v
D6806 = 95.40v
D6814 = 15.06v

Here are some of the voltages I measured from the MAIN Logic Board.

Main Board___________Main Board____________Main Board
IC9003 (D9D320)______IC7702 (00GA3W)______IC9001 (D9D320)
Pin1 = 3.468v_________Pin1 = 3.325v_________Pin1 = 3.453v
Pin2 = 0.775v_________Pin2 = 0.800v_________Pin2 = 0.0029v
Pin3 = 5.290v_________Pin3 = 0.0v___________Pin3 = 5.259v
Pin4 = 2.512v_________Pin4 = 0.0v___________Pin4 = 2.509v
Pin5 = 0.0v___________Pin5 = 5.00v__________Pin5 = 0.0015v
Pin6 = 3.402v_________Pin6 = 0.0v___________Pin6 = 5.004v
Pin7 = 8.260v_________Pin7 = 0.0v___________Pin7 = 9.909v
Pin8 = 12.840v________Pin8 = 5.01v__________Pin8 = 12.799v
(Chassis GND)________(Chassis GND)_________(Chassis GND)

As I said any assistance in trying to fix this unit or advice on what my next step would be will be very much appreciated.

Regards
Stevie

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

Did you check the tcon fuse?

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

Should test CN641, and report both states, that's in standby which is plugged in but off, then turn on tv.

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

Mostly looking to see if you get anything on pins 3 and 25-28.

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

Thanks, guys, I appreciate your speedy replies and help. I will test again and report back.
Cheers

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

Did you check the tcon fuse?

No I wasn't aware there was a Tcon fuse, But I will find it and check it out.
Thanks for your assistance...

[budm]

Re: Sony KD49X8005C Assistance Required Please.

We need good clear pictures of the whole back side of the TV showing how all the boards are connected together.
3- BL-ON--------------- 0.0v Pin 7. What is this pin 7 showing on the reading?
7- AC-OFF-DET--------- 3.49v pin 3. What is this pin 3 showing on the reading?
24- T-Con-ON--------- 0.0v
2- DC-Dimmer--------- 0.0v
4- PWM-Dimmer------- 0.0v
So far the main board is not sending the command signals for:
BL-ON to turn on backlights.
T-CON ON to turn on switched 12V to run the T-CON board.
Dimming control.

Backlights Error needs to be verified to see if >3V is normal condition or fault condition.

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

3- BL-ON------------0.0v Pin 7. What is this pin 7 showing on the reading?
7- AC-OFF-DET----3.49v pin 3. What is this pin 3 showing on the reading?

Pin 3 and Pin 7 are connected together on the back side of the SMPS board via R6431(4k7), D6405, R6428(100Ω).

Below are the pictures of both sides of the SMPS, MAIN and Tcon boards.
It's quite hard to fit the full board into the shot and make all the text easily read, as some of the text is pretty small.
If you need me to focus on any part of the board, I can zoom into that section to make it more legible.

I have now checked the Tcon fuse F1 (5A 125v) OK

How would I go about verifying if 3v is the normal or fault condition?
I have searched the net for a schematic, but I'm unable to locate one for this model.

Thanks one more guys....

Regards
Stevie

[zomi]

Re: Sony KD49X8005C Assistance Required Please.

Did it take the firmware update or just do nothing..

a common problem these was the mainboard would get bricked by software update,
as can be seen by the high prices of sony mainboards for these.

[Diah]

Re: Sony KD49X8005C Assistance Required Please.

this is android system. do the following for Hard reset
1- plug the tv out from wall socket
2- press on the TV panel on side (power) and ( volume -) keep press then plug the TV at wall socket , keep press until the LED indicator change from white to green

you can repeat this white you have the last firmware pkg on usb formatted to FAT32 and plugged at USB 2 on the TV not USB 3 the blue one

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

Did you try the usb update procedure? directions here if you do it follow directions exactly as given, it tells you what to expect if it is successful or not. https://www.sony.co.uk/electronics/s...loads/00015062

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

If your TV has a TV Energy Saving Switch (at the back or side of the TV) check that it is ON.

[kart24]

Re: Sony KD49X8005C Assistance Required Please.

How would I go about verifying if 3v is the normal or fault condition?
I have searched the net for a schematic, but I'm unable to locate one for this model.

Thanks one more guys....

Regards
Stevie

from here looks like bl_err is connected to ic 6801 thru a transistor, check for the part no, find out what that pin does?

[nomoresonys]

Re: Sony KD49X8005C Assistance Required Please.

Need feedback, did you try the reset in post #10?

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

Thanks again guys for your assistance, I really appreciate your help.
I have tried the reset from post#10, but no change,
There is no energy saving switch on the side
The Transistor from IC6801 has the marking (A4T5Q)

I have attached a couple of pictures showing where Pin 3 goes to.

I will test voltages again, with tv in standby mode, and after pressing the power button.

I will also report back with info of where BL_ERR (pin3) branches out to.

Regards Stevie.

[Diah]

Re: Sony KD49X8005C Assistance Required Please.

I have tried the reset from post#10, but no change,.

when you did it correct the reset did the white LED change to GREEN or not ?

if no change to green then your boot loader at safe mode because of fault at 99% shorted LED back light

if changed to Green you need to keep it for at least 30 minute it will restart twice.

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

Yes the white light changed to green, and then went out, But there is no change to the state of the tv.
I might not have given it enough time.
I'll do it again, and this time leave it at least 30 minutes after the light goes green.
Thank again....

[Diah]

Re: Sony KD49X8005C Assistance Required Please.

after it change green keep press both power and volume- for more5-8 second to be sure the boot loader reset it self and load again.. after 30 minute or less you should hear start music

[Stevie406]

Re: Sony KD49X8005C Assistance Required Please.

after it change green keep press both power and volume- for more5-8 second to be sure the boot loader reset it self and load again.. after 30 minute or less you should hear start music

I got the green light, and continued to hold buttons for 10-12 seconds,
The green light came on for 10 seconds then went out.
White light came on again for 15 seconds, then went out.
Waited for 60 minutes, no music. Still a blank screen.

[budwich]

Re: Sony KD49X8005C Assistance Required Please.

it would appear that the bl-er is set so that will likely shut down the system. A tester doesn't provide the "full story" although it does give you a chance to test the entire string... but the system monitors the operating current and if that is out range... which the tester can't really check, then the system will error.

what is the history of the set?