Samsung UE70TU6905 BACKLIGHTS AND SOUND ON NO PICTURES BUT SCREEN NOT DARK

[Diah]

also put back the cable ANA_DIM in the socket.,
the feed back points are marked by lotas post#77

[bohaboha]

also put back the cable ANA_DIM in the socket.,
the feed back points are marked by lotas post#77

I made the test with jumper on those point market By Lotas and Pin2 unhooked . what do you think that result i get in my last post ?

[Diah]

the part of panel at yours last test which didnt show picture are shorted.... you need to show here the buffer boards of this part if there any esd diode installed on it

[bohaboha]

the part of panel at yours last test which didnt show picture are shorted.... you need to show here the buffer boards of this part if there any esd diode installed on it

Hello new day new attempts. I have done new tests with ANA_DIM pin 2 disconnected and with jumper on feed back points.
looking to the screen
1) The left buffer board removed = no picture backlight on the TV goes in start loop and STB flash 3 times 3 flash.
2)the middle and the left buffer board connected start with the logo for two to 3 seconds, then no picture but backlight on, then goes in the start loop with STB flash 3 times 3 flash.
3)only middle buffer board attached = see attached picture no loop and no STB flash .
Diah here some pictures of the buffer board as you asked
pictures order from left to right 135133,135122,13508,134759,134708,134551 and 134502

[Diah]

we said put back ANA_DIM. and connect the left and middle side only.. see if there loop or not

[bohaboha]

we said put back ANA_DIM. and connect the left and middle side only.. see if there loop or not

ok sorry and with or without the jumper on feed back points? did you find that esd Diode on buffert board

[Diah]

all work now with jumper.. later after the issue cleared u can remove it

2 esd

[bohaboha]

all work now with jumper.. later after the issue cleared u can remove it

2 esd

with ANA_DIM pin in place and the jumper and the left and middle side connected the TVn shows the logo then start loop

[Diah]

with ANA_DIM pin in place and the jumper and the left and middle side connected the TVn shows the logo then start loop

remove the jumper and do same test.. see if the screen show ... keep it in loop so you can check the esd diode if one of them got warm

[bohaboha]

remove the jumper and do same test.. see if the screen show ... keep it in loop so you can check the esd diode if one of them got warm

with jumper and a smal tape on the left U ribcon it shows a picture on all the Screen for 3 second then loop. the esd diode never get warm in any situation with or with out a Jumper but maybe that IC near it or a capacitor are bad but no heat on them.
I am having problem to get into the Forum site from home i am answering from Bibliotek att home i get "connection not private " and not secure site ,
hope i will fix it soon.
i realy do not know what to do next maybe i ll go on with tape trying .but is ist problem with jumper and tape or i have to remouve the jumper to try the tape ?
thank you very much for your help

[bohaboha]

Hi without a jumber the backlight is on black (bleue) screen no pictures but no loop anymore and no components get hot on the screen ribbon even the esd diodes . the set do not respond to the RC yet..

[lotas]

Hi without a jumber the backlight is on black (bleue) screen no pictures but no loop anymore and no components get hot on the screen ribbon even the esd diodes . the set do not respond to the RC yet..

Because without the LVDS cable the motherboard does not see the panel and blocks all output voltages to the panel, that is why the jumper is installed (panel - motherboard feedback (T-CON)).

[bohaboha]

Because without the LVDS cable the motherboard does not see the panel and blocks all output voltages to the panel, that is why the jumper is installed (panel - motherboard feedback (T-CON)).

yes now i understand thank you. now how to test those 2 esd diod Diah " 5R2P " pointed in the pics and no component get warm all over the buffer boards

[lotas]

yes now i understand thank you. now how to test those 2 esd diod Diah " 5R2P " pointed in the pics and no component get warm all over the buffer boards

Yes, there were never any problems with them, here in the photo there are control points, check the resistance with a multimeter between them (between 1 and 2, between 1 and 3,...., between 2 and 3, between 2 and 4, and so on) and between the ground, there should not be low resistance.

[bohaboha]

Yes, there were never any problems with them, here in the photo there are control points, check the resistance with a multimeter between them (between 1 and 2, between 1 and 3,...., between 2 and 3, between 2 and 4, and so on) and between the ground, there should not be low resistance.

Hi Lotas if I have understood correctly i should measure the points between them, that is, 1 against 2,3,4 to number 14
Then all the points in the same way.
test the points to the GND from left to right:
266.5k ohms most points except 2 which is 3325.6k ohms
The points in between are quite mixed very hard to report everything here from: 09895mH, 1.755m ohms this for the first point against the others.
If you want me to report everything I'll find to record values without typing one by one and then write here
Or maybe a few points are enough. thank you

[Diah]

post photos with remark on yours original MB and the replacement only on LVDS socket and front IR-LED indicator socket and WIFI socket

[bohaboha]

post photos with remark on yours original MB and the replacement only on LVDS socket and front IR-LED indicator socket and WIFI socket

Hi Diah here some pictures of both boards the native one has hand written notes on it
the first row of pictures is the old one