Samsung LED UHD TV - Bad Main Board or Bad T-Con Board? Pictures inside

[E--Man]

Hi All,

Thanks for reading. Based on the interesting fact that the vertical lines issue don't seem to effect the menus whatsoever but rather everything around the menu regardless of video is shown, I'm trying to set mine whether the issue is the main board or the t-con board.

Again what's baffling is that the menu is not effected whatsoever. However, any other video displayed regardless of inputs or when no inputs exist exhibits the vertical lines and seem to effect black areas only.

The lines are green in color when the tv is in "Game Mode" and white in color when not in "Game Mode". Already tried service menu factory reset and switching the MRT "Lvds Format" which did not help.

Any definitive feedback would be appreciated!

[Diah]

model name ?

[E--Man]

model name ?

I am not home at the moment but believe it is un75hu 8000 series.

Please let me know what you think and thanks

[Diah]

i would start cleaning the LVDS from both side first then .resetting them. if didn't help then MB. but its is easy issue could be repaired not for replace... clear high resolution photo will help

[E--Man]

i would start cleaning the LVDS from both side first then .resetting them. if didn't help then MB. but its is easy issue could be repaired not for replace... clear high resolution photo will help

First, thanks for replying. Funny you said that because I already tried cleaning the LVDS connections yesterday between them but it didn't help. Also tried isolating which IC could be defective to trigger a change with low heat but it didn't help. I'll definately get you a high res photo. Do you want both boards or just MLB? No issue getting both if u think it'll help.

[E--Man]

i would start cleaning the LVDS from both side first then .resetting them. if didn't help then MB. but its is easy issue could be repaired not for replace... clear high resolution photo will help

Here are the pics as requested. Anything you find will be very appreciated.
If the resolution of these pics are not high enough just let me know and I will take even better ones.

[Diah]

from yours photo , the menu also effected with lines.. at least half screen could be seen, need to disconnect a time each half screen & also U ribbon on panel buffer boards a time to see if you will have 3/4 clear screen ..

[E--Man]

from yours photo , the menu also effected with lines.. at least half screen could be seen, need to disconnect a time each half screen & also U ribbon on panel buffer boards a time to see if you will have 3/4 clear screen ..

Hi Diah,

Could some the menu being effected have to do with the "Menu Transparency" setting? This setting is found in the System -> Accessibility menu.

Please see the difference between Menu Transparency setting set to "Low" and "High" on the attached photos. The lines can still be seen on the "Low" setting but not as much as the "High"setting. Unfortunately there is no" Off" setting for the transparency!

[Diah]

more or less you have them with menu.. so need diagnosing from the bottom .. go to panel buffer boards and disconnect one side U ribbon... for both side... no change then disconnect half panel each time from t-CON

[E--Man]

more or less you have them with menu.. so need diagnosing from the bottom .. go to panel buffer boards and disconnect one side U ribbon... for both side... no change then disconnect half panel each time from t-CON

I do not understand something. If I disconnect any connection in either T-Con or any of the U-Ribbons in any Buffer Control Boards then the entire screen goes black until restart. If I restart without ALL of the connections existing then all the entire screen is black, so how to diagnose? I cleaned all ribbon contacts and reseated - no difference.

Are you sure this is the correct path and it's not either T-Con board or Main board is the issue?

Thanks again.

[E--Man]

more or less you have them with menu.. so need diagnosing from the bottom .. go to panel buffer boards and disconnect one side U ribbon... for both side... no change then disconnect half panel each time from t-CON

This is what the picture looks like when you disconnect one side U-Ribbon from both bottom buffer control boards. What does this mean?

Disconnecting ANY cable from the T-Con results in black screen until restart.

[Diah]

This is what the picture looks like when you disconnect one side U-Ribbon from both bottom buffer control boards. What does this mean?

Disconnecting ANY cable from the T-Con results in black screen until restart.

Man i wrote one U ribbon at buffer boards a time then you will have 3/4 screen.and report back if the screen clean or not...... not as you did the bother disconnected..
please upload photo on whole the back of the Tv to see how and where the 12V T-CON come from..
al

[E--Man]

Man i wrote one U ribbon at buffer boards a time then you will have 3/4 screen.and report back if the screen clean or not...... not as you did the bother disconnected..
please upload photo on whole the back of the Tv to see how and where the 12V T-CON come from..
al

Sorry if I misunderstood. When I disconnect one U-Ribbon the whole screen is black. Can you please be a bit more specific on exact steps?

Picture uploaded as per your request

[Diah]

now its clear that you have vertical and horizontal puffer boards, so when you disconnect one side left or right need disconnect the both on the side top and down one

one things more yours t-con take the 12V from the PSU... so please show the socket which it go to main boards.there should be print chart of the socket to know the pins name... so next step f it need to test T-CON and panel as stand alone

[E--Man]

now its clear that you have vertical and horizontal puffer boards, so when you disconnect one side left or right need disconnect the both on the side top and down one

one things more yours t-con take the 12V from the PSU... so please show the socket which it go to main boards.there should be print chart of the socket to know the pins name... so next step f it need to test T-CON and panel as stand alone

To confirm, you are saying disconnect BOTH U-Ribbon cables as shown in the attached picture as example? If yes, then when I do that I only get black screen with nothing. Also tried restarting and nothing.

If I am not understanding, can you please point what I should disconnect in the picture? Thanks again.

[Diah]

leave the U ribbon connected... what about if you disconnect half screen from T-con ribbon same way on top and down ?
if the screen remain black it mean we have opposite buffer boards will explain later

[E--Man]

leave the U ribbon connected... what about if you disconnect half screen from T-con ribbon same way on top and down ?
if the screen remain black it mean we have opposite buffer boards will explain later

Disconnecting ANY cable from the T-Con results in black screen. Maybe due to failsafe or board configured to stop displaying if it detects nothing plugged in?

[Diah]

Disconnecting ANY cable from the T-Con results in black screen. Maybe due to failsafe or board configured to stop displaying if it detects nothing plugged in?

i don't think so, since the panel operated with double buffers boards , much likely panel_VCC designed in way running over the whole rand of the screen. as usual we don't have any exact info on panel design.
this why you need to try running the T-CON and Panel in stand alone mode... i asked on the print chart of PSU socket ..i will write here points of this try testing
1- first of all disconnect the sockets between PSU and MB. to see if the LED BL come ON, in case yes ..check the Fuse on T-CON close the black socket which it connected to PSU if there 12V DC with reference to TV chassis. ( i don't think there will be 12V )
2- measure on the PSU socket to know which pin Standby >3.3V and which Pin Power_on and if there one DRV_ON or T-CON ON the name yyou will know from the print chart on PSU
after you notice all above and in this case of test you are ready to go further

3- we keep the socket between PSU and MB disconnected, and disconnect the 2 LVDS from T-CON side
4- here need we use 1KR to jumper the pins called DRV_On or Panel_ON or T-CON_ON what ever which responsible to turn on the 12V to T-CON with any PIN STBY on the socket or any other PINS which it had >3.3V

if we are lucky the screen will turn on pattern color and at this point need to inspect if there are lines or not.. no lines mean T-CON and panel are fine.

[E--Man]

i don't think so, since the panel operated with double buffers boards , much likely panel_VCC designed in way running over the whole rand of the screen. as usual we don't have any exact info on panel design.
this why you need to try running the T-CON and Panel in stand alone mode... i asked on the print chart of PSU socket ..i will write here points of this try testing
1- first of all disconnect the sockets between PSU and MB. to see if the LED BL come ON, in case yes ..check the Fuse on T-CON close the black socket which it connected to PSU if there 12V DC with reference to TV chassis. ( i don't think there will be 12V )
2- measure on the PSU socket to know which pin Standby >3.3V and which Pin Power_on and if there one DRV_ON or T-CON ON the name yyou will know from the print chart on PSU
after you notice all above and in this case of test you are ready to go further

3- we keep the socket between PSU and MB disconnected, and disconnect the 2 LVDS from T-CON side
4- here need we use 1KR to jumper the pins called DRV_On or Panel_ON or T-CON_ON what ever which responsible to turn on the 12V to T-CON with any PIN STBY on the socket or any other PINS which it had >3.3V

if we are lucky the screen will turn on pattern color and at this point need to inspect if there are lines or not.. no lines mean T-CON and panel are fine.

Just started I'm on #4. Good news is that there are 2 fuses on the T-Con and both have 12.8 with reference to chassis and the backlight does come on with PSU to MB disconnected.

See pics for #4:
CNM803 = PSU to MB
CNT804 = PSU to T-Con

Can you please rephrase which pins to jumper?

[E--Man]

Also posting picture of BL ON when PSU disconnected from MB. I notice that the sides of the screen show the BL but not in center of screen. Not sure if this is normal or not based on the technology