Insignia TV fried my NEW power board. PLEASE HELP.
Hello everyone!
I'm new to this forum, and not extremely experienced with circuitry, so please bear with me while I beg for help.
So I was given a used Insignia TV that had stopped turning on (see attatched picture, Model# NS-48D42NA16). Specifically, when plugged in, the standby light would turn on, then blink red (from what I've gathered, this signifies an error in the powering on process). I took the back off of the TV, and inspected the power board. I checked to see if any capacitors were bulging first, because I've heard that's one of the most common causes of a power board failure, they all looked fine to the naked eye. I did however, find 2 components on the back of the board that appeared to be "fried" (they looked burnt, and one actually had a chunk blown off of it, exposing metal underneath). I later found these to be black square transistors soldered to small heatsinks (I looked up the part# on them. see attatched picture). Some of the small black square components next to them appeared "fried" as well (I think these are small resistors?). I did not think I could successfully replace the transistors, so I simply purchased a new power board (or rather, a used one from a reputable dealer on ebay)
This is where things went off the rails. $40 and 2 weeks later I had my new power board, which appeared in excellent condition, and installed it. I reassembled the TV, and plugged it in. It immediately came on, defaulted to HDMI 2, and displayed the "no signal" message. Everything worked great... for about 25 seconds. I then leaned the TV ever so slightly against the wall so that I could find the HDMI cable to plug it in, and IMMEDIATELY there was a loud "POP" and the screen went black again.
I unplugged the TV, plugged it up again, and lo and behold, that same flashing red light. I took the board back out, and wouldn't you know it, the same transistors on the NEW board look fried!
That was about 4 hours ago, and frankly I'm at a loss. I'm currently waiting to hear back from the board seller about returning the board, but what are the odds that the 2 boards would fail the EXACT same way? But what outside of the power board could cause the failure? There is a plastic guard in place between the power board and the body of the TV, so I wouldn't think it could have shorted out against the TV. I apologize for the long message, but I want to be as descriptive as possible. I'm new to the world of forums, as I've been living under a rock, so please excuse me if I don't have proper forum ediquite. Thank you to anyone who tries to help, I'm in DESPERATE need!
I'm new to this forum, and not extremely experienced with circuitry, so please bear with me while I beg for help.
So I was given a used Insignia TV that had stopped turning on (see attatched picture, Model# NS-48D42NA16). Specifically, when plugged in, the standby light would turn on, then blink red (from what I've gathered, this signifies an error in the powering on process). I took the back off of the TV, and inspected the power board. I checked to see if any capacitors were bulging first, because I've heard that's one of the most common causes of a power board failure, they all looked fine to the naked eye. I did however, find 2 components on the back of the board that appeared to be "fried" (they looked burnt, and one actually had a chunk blown off of it, exposing metal underneath). I later found these to be black square transistors soldered to small heatsinks (I looked up the part# on them. see attatched picture). Some of the small black square components next to them appeared "fried" as well (I think these are small resistors?). I did not think I could successfully replace the transistors, so I simply purchased a new power board (or rather, a used one from a reputable dealer on ebay)
This is where things went off the rails. $40 and 2 weeks later I had my new power board, which appeared in excellent condition, and installed it. I reassembled the TV, and plugged it in. It immediately came on, defaulted to HDMI 2, and displayed the "no signal" message. Everything worked great... for about 25 seconds. I then leaned the TV ever so slightly against the wall so that I could find the HDMI cable to plug it in, and IMMEDIATELY there was a loud "POP" and the screen went black again.
I unplugged the TV, plugged it up again, and lo and behold, that same flashing red light. I took the board back out, and wouldn't you know it, the same transistors on the NEW board look fried!
That was about 4 hours ago, and frankly I'm at a loss. I'm currently waiting to hear back from the board seller about returning the board, but what are the odds that the 2 boards would fail the EXACT same way? But what outside of the power board could cause the failure? There is a plastic guard in place between the power board and the body of the TV, so I wouldn't think it could have shorted out against the TV. I apologize for the long message, but I want to be as descriptive as possible. I'm new to the world of forums, as I've been living under a rock, so please excuse me if I don't have proper forum ediquite. Thank you to anyone who tries to help, I'm in DESPERATE need!
Attached Files
Comment