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

[Diah]

no i dit not solder anything on the board and the jumper i desoldered one side of it but leave it there for further test if it needs.
is the pictures good for your request?

then you have different between the 2 boards function.

[bohaboha]

then you have different between the 2 boards function.

somehow it have to be some difference it is a board for 58inch and mine is a 70 inches as you know but i follow your recommendations you said any even number should work i know it is not a guaranty but do you think it will work ?.

[Diah]

as i know TU even size MB have only one LVDS, the odd have 2.
however i would like you start the TV with out any socket of WIFI and front IR, let us testing in such condition only.. the jumpers must be in place

[bohaboha]

as i know TU even size MB have only one LVDS, the odd have 2.
however i would like you start the TV with out any socket of WIFI and front IR, let us testing in such condition only.. the jumpers must be in place

Sorry Diah i do not understand what do you mean with "start the TV with out any socket of WIFI and front IR," take away the wifi connection and the jumper it is ok but the other ????

[Diah]

MB with jumpers, connected only to power boards and screen.... no other sockets of wifi or front LED indicator IR FB

[bohaboha]

MB with jumpers, connected only to power boards and screen.... no other sockets of wifi or front LED indicator IR FB

resolt : The set starts with backlight on Screen black then loop the screen get a bit clear like if it wants to clunch then black and so on

[Diah]

keep it in this test mode... just disconnect half screen a time

[Diah]

you have panel issue ....... check the LVDS socket ( red circle ) if there short contact !.. after you clear this, do only masking on the blue marked area..

[bohaboha]

keep it in this test mode... just disconnect half screen a time

Left U ribbon disconnected loop with lite Screen then black every start is with lite screen.
same with the right U ribbon disconnected
but with only the middle connected without the left and right side that part is steady no more loop you can se the picture in post 104

[bohaboha]

you have panel issue ....... check the LVDS socket ( red circle ) if there short contact !.. after you clear this, do only masking on the blue marked area..

the test is between those 2 red point or to ground ?

[Diah]

zoom in the photo.. you will see 2 pins are like connected together,, u need to clean them.... also remove the jumpers totally u don't need it any more.... work on the panel , masking or scrap it

[bohaboha]

zoom in the photo.. you will see 2 pins are like connected together,, u need to clean them.... also remove the jumpers totally u don't need it any more.... work on the panel , masking or scrap it

no Diah it is not a short some particule on it it is clean now and it looks ok. instead of scraping the set why not move some component from 58 inches board to the 70 inches like the DC to DC chip and try the old board this is if it is not possible to use this one on the 70 inches .
and i do have a board for 65 inches that have only one LVDS to the Screen it looks identical to the 70 inches
i ll post some pictures of them all to se the differences

[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 am waiting your response about my answer very curious how the test should be done thank you

[bohaboha]

Hi again here the pictures of the 3 Mainboards they are almost identical only the 65 inches which differs with the others with socket on the upper left corner and it is active but probably they are not compatible as the 58 inches dealt with in this thread does not correspond to this Screen and neither for the remote control maybe it needs to be reprogrammed (region issue )

[Diah]

from start before you missed with 70MB, you have the issue on Panel,
70, and the one you said 65 they have only T-C Tuner, the 58 have T-C-S Tuner, i i did wrote before its had different at function, could be the wiring of IR socket different too this why no RC function.
you can try 65 with out jumpers bur disconnect the left and right U ribbon., to avoid Panel short effected the MB

[bohaboha]

from start before you missed with 70MB, you have the issue on Panel,
70, and the one you said 65 they have only T-C Tuner, the 58 have T-C-S Tuner, i i did wrote before its had different at function, could be the wiring of IR socket different too this why no RC function.
you can try 65 with out jumpers bur disconnect the left and right U ribbon., to avoid Panel short effected the MB

Hi first I want to thank everyone so much for the help I have received and am getting from the wonderful and patient Members of this forum and especially you Diah .I can surely try with 65 inches but I don't expect much from this try. Diah I think the problem lies in the fact that the Mainboard doesn't get the right current strength from the power supply when it comes to I think 5V because there is this 2.5V ANA_DIM which is a bit strange or what do you think?
I think I have to find the right values for them to be sure, maybe someone here who has the same board that can enlighten us about it

[Diah]

you are diving at wrong Ocean, .. ANA_DIMM absolute normal,, and yours PSU BL ok too..
i just test for you 55KU MB with PSU with out BL and screen.. ANA_DIMM pins No 2 was reading 1.65V before the MB go to loop because no BL.

[bohaboha]

you are diving at wrong Ocean, .. ANA_DIMM absolute normal,, and yours PSU BL ok too..
i just test for you 55KU MB with PSU with out BL and screen.. ANA_DIMM pins No 2 was reading 1.65V before the MB go to loop because no BL.

this is creasy no more loop now without the jumper but still no picture and no response from RC. maybe have to look for the programming side.

i have an other idea : i have the power supply for that 65 inches if i swap both Mainboard and Power Supply and give it a try hopefully i have the STB contact you know i sell TV parts on E-Bay so i have some parts i use to take all the parts from the set i find.
i hope it does not hurt the screen what do you suggest for this

[Diah]

i just wounder from long time you are testing ,, if the lvds cable contact pins didn't broken.. lol

[bohaboha]

i just wounder from long time you are testing ,, if the lvds cable contact pins didn't broken.. lol

you think really it can be i ll check it .i will just test the voltage on the 70 inches PS just to know what value those small volt should be to elimite my doubt about it.