This is not just for this tv but a few other models I have encountered this problem and I just don't really know how to proceed for a repair.
Originally had a bad backlight inverter. I fix the board, plug the set back in, and the backlight turns on for all of 2 seconds before going dark. I also noticed that the left side of the screen is considerably dimmer during those 2 seconds of being on. No clue as to why this is happening.
I also had someone bring in a sceptre 42" LCD with the same back-light symptom maybe 2 weeks ago and he said it turns on for 2 seconds then goes dark. I check it, and sure enough it does and one side is much dimmer than it should be. For that one, I swapped the backlight inverters with my known good ones from that same set I was selling and no difference. I ended up just trading him my sceptre set for his and some cash, but now I have 2 tvs that have this same problem.
Back to the JVC I currently have open.
Some of the CCFL's are the same brightness from left to right, and some are dimmer on the left side, so I swapped one of the dim ones with the top one which seemed to be at a good brightness, but it seems like the top one got dim and the dim one when in place of the top one was normal again. I checked continuity, I cleaned with isopropyl everything seems like it should work but obviously it does not.
To me it sounds like the CCFL's are just old and going out, but swapping a bright one with a dim one"When I say dim I mean has the left side being dim" just makes the bright one go dim and the dim one go bright. So now I think its not the CCFL's but nothing else would make sense. Also can someone explain to me how a CCFL can have one side dim and the other bright? Also I checked the boards that the CCFLS plug into and connectors on those and they are fine in terms of continuity.
Super confused and would like to understand this phenomenon.
Thanks
Originally had a bad backlight inverter. I fix the board, plug the set back in, and the backlight turns on for all of 2 seconds before going dark. I also noticed that the left side of the screen is considerably dimmer during those 2 seconds of being on. No clue as to why this is happening.
I also had someone bring in a sceptre 42" LCD with the same back-light symptom maybe 2 weeks ago and he said it turns on for 2 seconds then goes dark. I check it, and sure enough it does and one side is much dimmer than it should be. For that one, I swapped the backlight inverters with my known good ones from that same set I was selling and no difference. I ended up just trading him my sceptre set for his and some cash, but now I have 2 tvs that have this same problem.
Back to the JVC I currently have open.
Some of the CCFL's are the same brightness from left to right, and some are dimmer on the left side, so I swapped one of the dim ones with the top one which seemed to be at a good brightness, but it seems like the top one got dim and the dim one when in place of the top one was normal again. I checked continuity, I cleaned with isopropyl everything seems like it should work but obviously it does not.
To me it sounds like the CCFL's are just old and going out, but swapping a bright one with a dim one"When I say dim I mean has the left side being dim" just makes the bright one go dim and the dim one go bright. So now I think its not the CCFL's but nothing else would make sense. Also can someone explain to me how a CCFL can have one side dim and the other bright? Also I checked the boards that the CCFLS plug into and connectors on those and they are fine in terms of continuity.
Super confused and would like to understand this phenomenon.
Thanks
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