LGLN575s-ZE backlight

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  • chrle
    Senior Member
    • Sep 2013
    • 158
    • slovakia

    #1

    LGLN575s-ZE backlight

    hello,I buy this tv with no backlight,ordered leds from ebay,change burned leds,

    tv power on with dark spots ,on screen,all led are working.

    tv is powered 5 minutes then shut down and no backlight again,leds burned again.

    what cause led to burn ?

    wrong leds ?
  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: LGLN575s-ZE backlight

    Do you have the specification of the replacement LEDs?
    So the replacement LEDs failed again or the other original LEDs failed?
    We need more details and pictures.
    Never stop learning
    Basic LCD TV and Monitor troubleshooting guides.
    http://www.badcaps.net/forum/showthr...956#post305956

    Voltage Regulator (LDO) testing:
    http://www.badcaps.net/forum/showthr...999#post300999

    Inverter testing using old CFL:
    http://www.badcaps.net/forum/showthr...er+testing+cfl

    Tear down pictures : Hit the ">" Show Albums and stories" on the left side
    http://s807.photobucket.com/user/budm/library/

    TV Factory reset codes listing:
    http://www.badcaps.net/forum/showthread.php?t=24809

    Comment

    • chrle
      Senior Member
      • Sep 2013
      • 158
      • slovakia

      #3
      Re: LGLN575s-ZE backlight

      leds ---> LATWT470RELZK

      ordered from ebay ,ordered for 6916L-1214A backlight strip.

      will post pictures when I change leds

      Comment

      • dskall
        Badcaps Legend
        • Oct 2016
        • 2905
        • usa

        #4
        Re: LGLN575s-ZE backlight

        Sounds like you did not replace all bad leds.
        I assume no responsibility for any stupid suggestions I might post.

        Comment

        • chrle
          Senior Member
          • Sep 2013
          • 158
          • slovakia

          #5
          Re: LGLN575s-ZE backlight

          OK burned leds are changed,with new.all were different big leds.

          now backlight not turning off and not burning

          but I have problem when I put filters back (look on picture).
          Attached Files

          Comment

          • chrle
            Senior Member
            • Sep 2013
            • 158
            • slovakia

            #6
            Re: LGLN575s-ZE backlight

            and changed led are little different colour

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: LGLN575s-ZE backlight

              What are those small black ring on the LED's LENS?
              https://www.badcaps.net/forum/attach...5&d=1498750427

              BTW, make sure to go into on screen setup and turn down the Backlights level (not Brightness) as low as possible, that will extend the life of the LEDs.
              Last edited by budm; 06-29-2017, 09:46 AM.
              Never stop learning
              Basic LCD TV and Monitor troubleshooting guides.
              http://www.badcaps.net/forum/showthr...956#post305956

              Voltage Regulator (LDO) testing:
              http://www.badcaps.net/forum/showthr...999#post300999

              Inverter testing using old CFL:
              http://www.badcaps.net/forum/showthr...er+testing+cfl

              Tear down pictures : Hit the ">" Show Albums and stories" on the left side
              http://s807.photobucket.com/user/budm/library/

              TV Factory reset codes listing:
              http://www.badcaps.net/forum/showthread.php?t=24809

              Comment

              • chrle
                Senior Member
                • Sep 2013
                • 158
                • slovakia

                #8
                Re: LGLN575s-ZE backlight

                Originally posted by budm
                What are those small black ring on the LED's LENS?
                https://www.badcaps.net/forum/attach...5&d=1498750427

                BTW, make sure to go into on screen setup and turn down the Backlights level (not Brightness) as low as possible, that will extend the life of the LEDs.
                I changed plastic led lens from another LG tv.

                Comment

                • dskall
                  Badcaps Legend
                  • Oct 2016
                  • 2905
                  • usa

                  #9
                  Re: LGLN575s-ZE backlight

                  Those are not correct color. Also care must be taken to center lens over led
                  Last edited by dskall; 06-29-2017, 09:57 AM.
                  I assume no responsibility for any stupid suggestions I might post.

                  Comment

                  • chrle
                    Senior Member
                    • Sep 2013
                    • 158
                    • slovakia

                    #10
                    Re: LGLN575s-ZE backlight

                    this is now my big problem
                    Attached Files

                    Comment

                    • chrle
                      Senior Member
                      • Sep 2013
                      • 158
                      • slovakia

                      #11
                      Re: LGLN575s-ZE backlight

                      Originally posted by dskall
                      Those are not correct color. Also care must be taken to center lens over led
                      omg,yes now I need to take down lenses and center over led,and find what colour are original leds
                      Last edited by chrle; 06-29-2017, 10:07 AM.

                      Comment

                      • chrle
                        Senior Member
                        • Sep 2013
                        • 158
                        • slovakia

                        #12
                        Re: LGLN575s-ZE backlight

                        ok what to use to glue led lens?it is very difficult to center lens.

                        Comment

                        • dskall
                          Badcaps Legend
                          • Oct 2016
                          • 2905
                          • usa

                          #13
                          Re: LGLN575s-ZE backlight

                          I apply power to led. Makes it easy to center. Looking straight down no bright light coming out. I am still experimenting with glue
                          I assume no responsibility for any stupid suggestions I might post.

                          Comment

                          • zomi
                            Badcaps Veteran
                            • Nov 2011
                            • 505

                            #14
                            Re: LGLN575s-ZE backlight

                            try flexible superglue

                            Comment

                            • tvsteve2
                              Member
                              • Aug 2014
                              • 25
                              • usa

                              #15
                              Re: LGLN575s-ZE backlight

                              Locktite makes a supergel in a plastic bottle that you squeeze two blue side bars to dispense the glue. Also the old glue spots need scraped off smooth and the lenses put on level.

                              Comment

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