LG 55UB820V 4K Powers up but No Backlight

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  • london-freddie
    Badcaps Veteran
    • May 2015
    • 472
    • UK

    #21
    Re: LG 55UB820V 4K Powers up but No Backlight

    voltage at dr on pin is 1.56v and stays at 1.56v when backlights turn off

    Comment

    • vinceroger69
      Badcaps Legend
      • Mar 2012
      • 6714
      • uk

      #22
      Re: LG 55UB820V 4K Powers up but No Backlight

      i wonder if the voltage is too low budm maybe able too advise but with this mainboard atleast the dr on voltage stays on when backlights go off so possible failed/failing led maybe budm has some thoughts

      Comment

      • london-freddie
        Badcaps Veteran
        • May 2015
        • 472
        • UK

        #23
        Re: LG 55UB820V 4K Powers up but No Backlight

        Update:: sourced a replacement backlight from a new tv broken screen in transit. collecting it this evening.
        In anticipation of fitting the replacement backlight assembly I have again stripped my screen to remove the suspect backlight and have found 1 led not working, I have just replaced the open led and the backlights now come on and stay on,no screen panel fitted though
        So I assume once the replacement backlight is fitted all should be well, fingers crossed

        Comment

        • vinceroger69
          Badcaps Legend
          • Mar 2012
          • 6714
          • uk

          #24
          Re: LG 55UB820V 4K Powers up but No Backlight

          yes lets hope the replacement leds fixes your issue.

          Comment

          • london-freddie
            Badcaps Veteran
            • May 2015
            • 472
            • UK

            #25
            Re: LG 55UB820V 4K Powers up but No Backlight

            TV is now back together and working with my original led's after replacing the open led, The replacement backlight did not fit my tv,
            My screen is LC550EQE replacement screen is also LC550EQE but backlight fitted in the replacement screen is slightly different, ie screw mounting holes slightly different positions, and five less led's on replacement screen.

            Comment

            • vinceroger69
              Badcaps Legend
              • Mar 2012
              • 6714
              • uk

              #26
              Re: LG 55UB820V 4K Powers up but No Backlight

              Glad it was a easy fix lg leds do seem too fail a lot remember too turn the backlights down may help save the other leds

              Comment

              • Andrew F. Ali
                Badcaps Legend
                • Jan 2014
                • 2450
                • Trinidad & Tobago

                #27
                Re: LG 55UB820V 4K Powers up but No Backlight

                With LG you may have to turn the backlights setting to 65 for ALL the inputs.

                Comment

                • london-freddie
                  Badcaps Veteran
                  • May 2015
                  • 472
                  • UK

                  #28
                  Re: LG 55UB820V 4K Powers up but No Backlight

                  Yes have turned backlights down to 70, watching the tv now still fine

                  Comment

                  • Andrew F. Ali
                    Badcaps Legend
                    • Jan 2014
                    • 2450
                    • Trinidad & Tobago

                    #29
                    Re: LG 55UB820V 4K Powers up but No Backlight

                    Excellent!

                    Comment

                    • Mikeyboy2007
                      Badcaps Veteran
                      • Mar 2013
                      • 745
                      • Scotland

                      #30
                      Re: LG 55UB820V 4K Powers up but No Backlight

                      for anyone following this thread, i have same issue, but i got brand new LED strips from LEDBarz here in the UK, all the LEDs and string test ok but DR on is missing. now i jumped 3.5v standby to DR_on and the backlights fire up when tv is switched on. is it safe to leave this cable jumped or will it cause damage ? any help appreciated thanks.

                      and also the tv is stuck on LG screen, does it need a replacement main ?
                      Last edited by Mikeyboy2007; 03-12-2022, 08:23 AM.

                      Comment

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