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Thread Tools | Display Modes |
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#1 |
Member
Join Date: Feb 2017
City & State: paris
My Country: france
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![]() Hello,
I have my TV model UE50KU6070 which I am trying to repair. BN41-02528A / BN94-10800C motherboard. If I disconnect the motherboard from the power board, the backlight works. When the motherboard is connected the backlight works but the screen remains black. When I plug the TV into the electrical outlet, the standby LED lights up but no reaction to an attempt to start it with the remote control for about 1 minute. During this minute the TV consumes about 20W. After one minute the consumption drops to 0W and the TV can turn on with the remote control but the screen remains black. All voltages on the motherboard are correct. The TV turns off with the remote control but you have to wait about 1 minute before restarting it again. Sometimes at startup the screen displays "Samsung Smart TV" for 1 second before going black. In fact, in addition to the black screen, it is as if the TV was extremely slow. The behavior is the same if I disconnect the two LVDS cables. Do you have an idea of the problem and do you think that the motherboard is repairable for example by reprogramming the memory? Thank you in advance for your help. |
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#2 |
Leaking Member
Join Date: Dec 2014
City & State: Atlantic Canada
My Country: Canada
Line Voltage: Ground, 0Hz
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![]() Reflash the SPI or whatever it is. Looks like a good candidate, at least it’s worth a try if you can find a dump file. Also check the SPI first, before you put a new file on. Not that you have a bad one.
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#3 |
Member
Join Date: Feb 2017
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![]() Thank you CapLeaker.
Attached the SPI file but i have no idea whether the content is valid or not. Last edited by totof; 09-27-2022 at 03:31 PM.. |
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#4 |
Leaking Member
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![]() read the spi, save a copy, FF the spi and check it. Hopefully it is still good, then all you need is a working dump.
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#5 |
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Join Date: Feb 2017
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![]() SPI seems good, I wrote FF without problem
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#6 |
Badcaps Veteran
Join Date: Sep 2009
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![]() it is not a memory problem, must be checked the entire psb with dummy loads
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#7 |
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Join Date: Feb 2017
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#8 |
Badcaps Veteran
Join Date: Sep 2009
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![]() you don't know ohm's law? It's hard starting whatever repair without it , must collect some power resistors and a lamp..
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#9 |
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Join Date: Feb 2017
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![]() Thank you Davi.p
For the ohm's law it should be fine but the problem is that without a diagram of the card it is very difficult for me to know what to test. I have already checked all the voltages on the inductance and they are OK. No shorted capacitors either. What I would like to test are the signals to the LVDS cable but without a diagram it's complicated |
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#10 |
Badcaps Veteran
Join Date: Jan 2013
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![]() backlights and powerboard are fine, proved by results of first post.
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#11 |
Badcaps Veteran
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![]() maybe try the tape cut-off method just for fun, never know when it will work.
Last edited by nomoresonys; 10-05-2022 at 04:01 PM.. |
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#12 |
Badcaps Veteran
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![]() Capleaker probably nailed it with post #2, eeprom/spi/nand dead.
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#13 |
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![]() maybe we don't understand ourselves, i suggested you to test the power supply outputs, that are usually marked on board each signal, put a resistor on the 5v, a lamp on 12v and so on..
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#14 |
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![]() I rechecked all the voltages on self and they are good.
VON, VCCA, VCCB and AVDD voltages are also correct. I just bought another motherboard pulled from a broken TV and the TV works again. |
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