Hello,
some days ago my Samsung UE55H7080 broke. When I switched on the TV, the screen stayed black (2 hours ago I was still watching TV). The sound is still working, I can hear how I can switch channels, go into the menu and so on. I've already tried to plug the TV off for the whole night and plug it back on the next day and it didn't help.
I decided to open the TV because I thought it might be a problem with the power supply for the backlight. Attached you can find some pictures of the inside of the TV.
What I've already checked:
- The fuse on the supply board is ok
- I can't see any broken wires, bulged capacitors or similar.
- I've checked the voltages of the LED supply; they are as follows
CNL801A:
Pin 1 (N.C.) 0V
Pin 2 (N.C.) 0V
Pin 3 (L4+) 16.8V
Pin 4 (L4-) 0V
Pin 5 (L3+) 54.7V
Pin 6 (L3-) 0V
Pin 7 (L2+) 54.7V
Pin 8 (L2-) 0V
Pin 9 (L1+) 16.9V
Pin10 (L1-) 0V
CNL801B:
Pin 1 (N.C.) 0V
Pin 2 (R1+) 39.8V
Pin 3 (R1-) 16.9V
Pin 4 (R2+) 127.4V
Pin 5 (R2-) 54.7V
Pin 6 (R3+) 127.4V
Pin 7 (R3-) 54.7V
Pin 8 (R4+) 39.8V
Pin 9 (R4-) 16.8V
Pin 10 (N.C) 0V
What makes me wonder a little bit when looking at those voltage levels is, that they are not the same for left and right but I sadly haven't found a circuit diagram of the BN44-00715A in http://www.toms-service-manuals.com/ or elsewhere.
I also can't see any light coming through the tiny holes in the back of the tv when I plug it in and switch it on. I haven't tried that in the very dark yet though.
Do you have any suggestions what to check further? Mainly it would be interesting for me, where the failure is. If it is "only" the backlight or the screen.
Thanks in advance.
some days ago my Samsung UE55H7080 broke. When I switched on the TV, the screen stayed black (2 hours ago I was still watching TV). The sound is still working, I can hear how I can switch channels, go into the menu and so on. I've already tried to plug the TV off for the whole night and plug it back on the next day and it didn't help.
I decided to open the TV because I thought it might be a problem with the power supply for the backlight. Attached you can find some pictures of the inside of the TV.
What I've already checked:
- The fuse on the supply board is ok
- I can't see any broken wires, bulged capacitors or similar.
- I've checked the voltages of the LED supply; they are as follows
CNL801A:
Pin 1 (N.C.) 0V
Pin 2 (N.C.) 0V
Pin 3 (L4+) 16.8V
Pin 4 (L4-) 0V
Pin 5 (L3+) 54.7V
Pin 6 (L3-) 0V
Pin 7 (L2+) 54.7V
Pin 8 (L2-) 0V
Pin 9 (L1+) 16.9V
Pin10 (L1-) 0V
CNL801B:
Pin 1 (N.C.) 0V
Pin 2 (R1+) 39.8V
Pin 3 (R1-) 16.9V
Pin 4 (R2+) 127.4V
Pin 5 (R2-) 54.7V
Pin 6 (R3+) 127.4V
Pin 7 (R3-) 54.7V
Pin 8 (R4+) 39.8V
Pin 9 (R4-) 16.8V
Pin 10 (N.C) 0V
What makes me wonder a little bit when looking at those voltage levels is, that they are not the same for left and right but I sadly haven't found a circuit diagram of the BN44-00715A in http://www.toms-service-manuals.com/ or elsewhere.
I also can't see any light coming through the tiny holes in the back of the tv when I plug it in and switch it on. I haven't tried that in the very dark yet though.
Do you have any suggestions what to check further? Mainly it would be interesting for me, where the failure is. If it is "only" the backlight or the screen.
Thanks in advance.
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