TCL 55S401 LED LCD TV no backlight

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  • shelby5041
    Badcaps Legend
    • Feb 2009
    • 1504
    • united states of america usa

    #41
    Re: TCL 55S401 LED LCD TV no backlight

    hi bud and beau i havent done any further testing busy with other things.. today though i brought tv in from garage and powered on and i can see the TCL logo light up for a fraction of a second and then backlight powers off (im thinking shutdown due to bad led) ... previously i tested outside and could not see this due to ambient light....so now i thinking that it is indeed a led issue and that this tv does not output power to the conne3ctor unless bacjklights plugged in and good...since replacing ps produced same results im pretty confident 99% that its bad LED which is what is normally the issue on most LCD LEd tvs when no backlight...the ps is typically not the issue.....in the old days with CCFL it was opposite..it was mostly ps/inverter issue and almost never lamp issue....most vifdeos have shown you shoyuld have voltage to the backlight connector even with backlights disconnected but apparently on this model that is not true since i have 0V with connector disconncted and yes bud maybe i was not testing the voltages at exact time in order to see the initital voltage(with BL connected) since its powering on only for a fraction of a second...all i do know is with connector disconnected to BL i have 0v and BL signal on.
    Last edited by shelby5041; 01-07-2020, 04:17 PM.

    Comment

    • shelby5041
      Badcaps Legend
      • Feb 2009
      • 1504
      • united states of america usa

      #42
      Re: TCL 55S401 LED LCD TV no backlight

      update beau and bud

      BBBBBBBBBad news

      i reluctantly removed the lcd panel....since i have damaged several in the past

      it was indeed 1 bad LED strip..unfortunately during my swapping out etc trying to isolate the bad led i fried my power supply

      thats actually the not so bad news....even worse , i cracked the LCD panel while handling

      i hate removing lcd panels and may consider not doing it anymore as it wastes a lot of time and the risk just isnt worth it

      thanks for all your help

      Comment

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