Voltage still applied to LED backlight stips when TV in standby?

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  • lmcancu
    Senior Member
    • Oct 2009
    • 158

    #1

    Voltage still applied to LED backlight stips when TV in standby?

    Is it normal that a voltage of 54 volts is still applied to the LED strips when the TV is in standby? There is not much current, but I can see several of the LEDs are on but very very dim. When the TV is turned on, the voltage jumps up to about 100v (there are 33x3v LEDs, I removed 3 bad ones)
  • Diah
    Badcaps Legend
    • Feb 2013
    • 6355
    • Germany

    #2
    Re: Voltage still applied to LED backlight stips when TV in standby?

    however you didn't wrote the TV type and model No. but i assume its first generation of LED Android TV.

    Comment

    • lmcancu
      Senior Member
      • Oct 2009
      • 158

      #3
      Re: Voltage still applied to LED backlight stips when TV in standby?

      Its an RCA RLDED 4331B: 43 inch LED TV (From 2015 I think). Not a smart TV

      Comment

      • Diah
        Badcaps Legend
        • Feb 2013
        • 6355
        • Germany

        #4
        Re: Voltage still applied to LED backlight stips when TV in standby?

        i see. its all in one boards. i think its just disorder at system power off / on. reset / hard reset could bring it back to normal / real power off.

        Comment

        • lmcancu
          Senior Member
          • Oct 2009
          • 158

          #5
          Re: Voltage still applied to LED backlight stips when TV in standby?

          Tried that and same issue, but one point I didn't mention is that I don't have the panel connected yet. I removed 3 LEDs from 2 of the strips (shorted them), so I have 33 LED lights instead of 36. The main board is just connected to power and the LED strips. The connection to the panel board (inverter board?) I haven't connected yet.
          I was just testing to make sure that the LED backlights work. They light up when I turn the TV on after 2-3 seconds, but when I turn the TV off, I see that some LEDs are very dim and there is still voltage being applied.
          Do I need to connect the panel for the voltage to go away when the TV is off?

          Comment

          • Diah
            Badcaps Legend
            • Feb 2013
            • 6355
            • Germany

            #6
            Re: Voltage still applied to LED backlight stips when TV in standby?

            its not good idea to jumper 3 Leds... it mean in total >=9V. and did the LED build in zener diode or with out..

            so in short words now the system in DIY way... disorder of power OFF / ON accurate

            about the screen.. did the T-CON integrated at Panel buffer boards in case yes... the point above will be in place.

            Comment

            • lmcancu
              Senior Member
              • Oct 2009
              • 158

              #7
              Re: Voltage still applied to LED backlight stips when TV in standby?

              Ok got it and thank you! I ordered new strips and was trying to make sure nothing else was wrong before they arrived. For the LEDs I removed, I just shorted positive and negative pads where the LED was with some solder. This shouldn't affect any zener diode protection in the strip?

              Comment

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