Hi all,
I've been fighting off and on with a 46" Samsung LED television someone gave me last year and still haven't gotten a definitive answer to narrow the problem down to which board I need to order.
Description:
It's pretty much dead, and doing that common thing where you can hear the relay clicking once every five or six seconds when you try to power it up, with no other signs of life.
Things I've tried:
One of the first was disconnecting the main 18-pin ribbon link between mainboard and PSU. Some info seemed to state that this was a way to make sure the backlights worked and all, as the PSU was supposed to automatically enable everything in that case. No go here, unfortunately. With the mainboard offline, the unit just sits dead with no clicking and no way to start it. I think someone or something implied that they may have changed that behavior, so I'm not positive that disconnecting it should have worked here.
Next, disconnecting the T-Con board. Same as before, just clicking relay and dead screen.
Disconnecting any/all of the remaining small cables does the same dead screen with relay clicks, with the exception of that 10-pin or whatever it is that goes to the power on circuitry in the front panel. If that's out, you have no way to start it.
Most of the main connector lines have really low voltages on them, often fluctuating. I think there are a few that hang around .3V, but the unstable ones are in the lower millivolts. I do get a solid 5.3V on the Standby pin there, and there's one other pin (P_DIM, I believe) which stays at 4V. The standby/power-on circuitry seems to work (remote or panel switch).
I also tried feeding the available 5V into the "BL_ON" line to see if I could start the lights, but I guess there's too much else wrong with the set in this state (no lights).
All fuses on the power board are intact, as is a small surface mount I saw on the T-Con board. There's also no sign of any poor condition electrolytic caps or any other visibly damaged components across the boards.
If there's any "tell tale" procedure I can try, or have already tried, I'd like to figure out what I need to order. FWIW, I also have rework equipment here, but it sounds as if most of the stuff that goes wrong ultimately requires the swapping of full boards. I also wouldn't have a clue as to the tracking of a failed part with this mess, unless there was some specific part which commonly fails on this model (and isn't proprietary).
Let me know if there's any other info which might help.
Much Thanks,
George
PS- There's a story behind this set, but I'm not sure how much stock to put in it. The relative who gave it to me says that a tech came out to look at it, and installed two boards which didn't fix it, and it would have needed a third. All three would have made the repair too costly, but I don't know why he would sell him all three if the first two weren't the problem, and I can't see every board in the thing being faulty. He also said that the TV came up at one point, with a blank blue screen or something, which was when the tech said he would need the third board. Again, I wasn't there nor do I know the tech or whether he was on the level.
I've been fighting off and on with a 46" Samsung LED television someone gave me last year and still haven't gotten a definitive answer to narrow the problem down to which board I need to order.
Description:
It's pretty much dead, and doing that common thing where you can hear the relay clicking once every five or six seconds when you try to power it up, with no other signs of life.
Things I've tried:
One of the first was disconnecting the main 18-pin ribbon link between mainboard and PSU. Some info seemed to state that this was a way to make sure the backlights worked and all, as the PSU was supposed to automatically enable everything in that case. No go here, unfortunately. With the mainboard offline, the unit just sits dead with no clicking and no way to start it. I think someone or something implied that they may have changed that behavior, so I'm not positive that disconnecting it should have worked here.
Next, disconnecting the T-Con board. Same as before, just clicking relay and dead screen.
Disconnecting any/all of the remaining small cables does the same dead screen with relay clicks, with the exception of that 10-pin or whatever it is that goes to the power on circuitry in the front panel. If that's out, you have no way to start it.
Most of the main connector lines have really low voltages on them, often fluctuating. I think there are a few that hang around .3V, but the unstable ones are in the lower millivolts. I do get a solid 5.3V on the Standby pin there, and there's one other pin (P_DIM, I believe) which stays at 4V. The standby/power-on circuitry seems to work (remote or panel switch).
I also tried feeding the available 5V into the "BL_ON" line to see if I could start the lights, but I guess there's too much else wrong with the set in this state (no lights).
All fuses on the power board are intact, as is a small surface mount I saw on the T-Con board. There's also no sign of any poor condition electrolytic caps or any other visibly damaged components across the boards.
If there's any "tell tale" procedure I can try, or have already tried, I'd like to figure out what I need to order. FWIW, I also have rework equipment here, but it sounds as if most of the stuff that goes wrong ultimately requires the swapping of full boards. I also wouldn't have a clue as to the tracking of a failed part with this mess, unless there was some specific part which commonly fails on this model (and isn't proprietary).
Let me know if there's any other info which might help.
Much Thanks,
George
PS- There's a story behind this set, but I'm not sure how much stock to put in it. The relative who gave it to me says that a tech came out to look at it, and installed two boards which didn't fix it, and it would have needed a third. All three would have made the repair too costly, but I don't know why he would sell him all three if the first two weren't the problem, and I can't see every board in the thing being faulty. He also said that the TV came up at one point, with a blank blue screen or something, which was when the tech said he would need the third board. Again, I wasn't there nor do I know the tech or whether he was on the level.
). Stupid question, but can each of these lights be individually powered by a "normal" LED supply (something in the 2V range with a current limiting resistor)? I actually have a supply dedicated to that here.
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