Hello all,
I'm working on a Seiki SE32HY27 LED TV. It was most likely the victim of a power surge, at which point I had the user unplug it, and it went from no power to power with no back lights.
I replaced the board, since this unit has the main and power board integrated into one unit, and the first replacement gave me no power, just a red indicator light. So, I exchanged that for another, which is back to powering on, but still no back lights.
I'm getting a reading of 48 volts from the LED power when the TV is on, and 41 volts when it's off. This unit has 3 strips of 8 LEDs, and from what I've seen, a typical white LED needs somewhere around 3.3v to power on, which would give me 26.4 volts per strip, if my math is right.
Right now I'm leaning toward trying to test each strip, but assuming that 48 volts for one strip would be too much. I'm debating digging up an old laptop power supply to test each strip, hoping that one strip has become shorted. Since the laptop power supply is rated 19.6 volts (at least, most of the newer ones I've seen are), is this going to be enough to power a whole strip?
Quick edit: I tested the individual strips for resistance, and every one of them reads infinite. While I find it hard to believe all 3 strips would typically go out at once, I set my meter to 20M ohms and still get the same reading, so I'm thinking the entire set of strips is bad?
I'm working on a Seiki SE32HY27 LED TV. It was most likely the victim of a power surge, at which point I had the user unplug it, and it went from no power to power with no back lights.
I replaced the board, since this unit has the main and power board integrated into one unit, and the first replacement gave me no power, just a red indicator light. So, I exchanged that for another, which is back to powering on, but still no back lights.
I'm getting a reading of 48 volts from the LED power when the TV is on, and 41 volts when it's off. This unit has 3 strips of 8 LEDs, and from what I've seen, a typical white LED needs somewhere around 3.3v to power on, which would give me 26.4 volts per strip, if my math is right.
Right now I'm leaning toward trying to test each strip, but assuming that 48 volts for one strip would be too much. I'm debating digging up an old laptop power supply to test each strip, hoping that one strip has become shorted. Since the laptop power supply is rated 19.6 volts (at least, most of the newer ones I've seen are), is this going to be enough to power a whole strip?
Quick edit: I tested the individual strips for resistance, and every one of them reads infinite. While I find it hard to believe all 3 strips would typically go out at once, I set my meter to 20M ohms and still get the same reading, so I'm thinking the entire set of strips is bad?
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