Count of Leds burnt in backlight POLL !?

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  • web5
    Member
    • Apr 2017
    • 21
    • US

    #1

    Count of Leds burnt in backlight POLL !?

    How many Leds you discovered Burnt when you openned TV ?

    I have TV with backlight stopped working, and
    before i start to tear down it, i would like to
    narrow down to the number of possible burnt Leds.
    ( Tested power supply - power does not go to led strips)
    12
    1-2
    0%
    3
    3-5
    0%
    6
    6-10
    0%
    1
    11-All
    0%
    2
  • chrismurphy
    Badcaps Veteran
    • May 2014
    • 251
    • australia

    #2
    Re: Count of Leds burnt in backlight POLL !?

    I think this is rather useless as every tv and tv's same model differs
    It wont help at all , what would be better is the working voltage of the strings for various models would be helpful , better still the running voltage using LED tester would help narrow the fault to LED panel or power supply driver

    Comment

    • web5
      Member
      • Apr 2017
      • 21
      • US

      #3
      Re: Count of Leds burnt in backlight POLL !?

      Originally posted by chrismurphy
      I think this is rather useless as every tv and tv's same model differs
      It wont help at all , what would be better is the working voltage of the strings for various models would be helpful , better still the running voltage using LED tester would help narrow the fault to LED panel or power supply driver
      Before i tear down tv for repair i would like to order some quantity of led
      replacements, and how many is more likely be enough.
      Tested yesterday, my 50" TV led supply puts 124.5 VDC.

      Comment

      • ReeceyBurger123
        Never Give Up !
        • May 2014
        • 7325
        • Britain

        #4
        Re: Count of Leds burnt in backlight POLL !?

        Ive had 18 out before in Lg 50"
        Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

        https://www.facebook.com/Telford-Tel...7894576335359/

        Comment

        • web5
          Member
          • Apr 2017
          • 21
          • US

          #5
          Re: Count of Leds burnt in backlight POLL !?

          Originally posted by ReeceyBurger123
          Ive had 18 out before in Lg 50"
          Wow, didn't expected that number !
          On Tube i see from 2 to 4 leds blown.

          Comment

          • freakaftr8
            Badcaps Legend
            • Oct 2012
            • 3743
            • USA

            #6
            Re: Count of Leds burnt in backlight POLL !?

            Originally posted by ReeceyBurger123
            Ive had 18 out before in Lg 50"
            Good god man that's a tv that doesn't want to be resurrected fro. The dead!!
            Did I leave the soldering iron on?

            Comment

            • dskall
              Badcaps Legend
              • Oct 2016
              • 2905
              • usa

              #7
              Re: Count of Leds burnt in backlight POLL !?

              Originally posted by web5
              Before i tear down tv for repair i would like to order some quantity of led
              replacements, and how many is more likely be enough.
              Tested yesterday, my 50" TV led supply puts 124.5 VDC.
              15 should be enough
              I assume no responsibility for any stupid suggestions I might post.

              Comment

              • web5
                Member
                • Apr 2017
                • 21
                • US

                #8
                Re: Count of Leds burnt in backlight POLL !?

                Originally posted by dskall
                15 should be enough
                1/5 of all leds in my tv, i think you are right.

                Comment

                • ReeceyBurger123
                  Never Give Up !
                  • May 2014
                  • 7325
                  • Britain

                  #9
                  Re: Count of Leds burnt in backlight POLL !?

                  Originally posted by freakaftr8
                  Good god man that's a tv that doesn't want to be resurrected fro. The dead!!
                  Tbh I dont know what happened as 6 were open and 12 shorted LG LN series always seem to fail badly
                  Please Do Not PM My Page Asking For Help Badcaps Is The Place For Advise, Page Linked For Business Reasons Only. Anyone Doing So Will Be Banned Instantly !

                  https://www.facebook.com/Telford-Tel...7894576335359/

                  Comment

                  • budm
                    Badcaps Legend
                    • Feb 2010
                    • 40746
                    • USA

                    #10
                    Re: Count of Leds burnt in backlight POLL !?

                    12 on SAMSUNG, 9 open, 3 shorted.
                    I would stock 50 of them (I order 100 at a time. How much is the price difference between 15 and 25 or 50?
                    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

                    • goontron
                      5000!
                      • Dec 2011
                      • 4108
                      • US

                      #11
                      Re: Count of Leds burnt in backlight POLL !?

                      The only LED TV i've worked on -- Vizio, 50" IIRC. struck by lightning. All LEDs open.
                      Things I've fixed: anything from semis to crappy Chinese $2 radios, and now an IoT Dildo....

                      "Dude, this is Wyoming, i hopped on and sent 'er. No fucking around." -- Me

                      Excuse me while i do something dangerous


                      You must have a sad, sad boring life if you hate on people harmlessly enjoying life with an animal costume.

                      Sometimes you need to break shit to fix it.... Thats why my lawnmower doesn't have a deadman switch or engine brake anymore

                      Follow the white rabbit.

                      Comment

                      • whiz62
                        whiz62
                        • Dec 2013
                        • 242
                        • usa

                        #12
                        Re: Count of Leds burnt in backlight POLL !?

                        Vizio 47", 4 LEDS open out of 54.

                        Comment

                        • augiedoggy
                          Senior Member
                          • Aug 2016
                          • 62
                          • united states

                          #13
                          Re: Count of Leds burnt in backlight POLL !?

                          I have found that about 30-40% of the tvs I just replace the burnt leds instead of the strips end up having another led failure shortly after. I think one of the reasons being is if an led shorts closed the voltage increases to all the other leds and stresses them. some tvs only have one shorted open led and thats all it sometimes takes to make the whole tv go dark and on other sets Ive had to replace as much as 5 bad leds. By far the most unreliable LEDS are the ones LG uses in their economy sets as well as many of the vizios they make. (I have an LG 47" set sitting here now I have to repair AGAIN after replacing the bad leds and having another fail 2 weeks later.)
                          Last edited by augiedoggy; 04-23-2017, 09:48 AM.

                          Comment

                          • dskall
                            Badcaps Legend
                            • Oct 2016
                            • 2905
                            • usa

                            #14
                            Re: Count of Leds burnt in backlight POLL !?

                            I am modifying the current supplies to the leds on vizio and LG. They run there current at 400ma+ on leds only rated for about 350ma. I want to set them below 350ma. Funny thing is I reduced max. current over 100ma with little noticeable change in brightness. Makes you wonder if it's calculated to kill the tv after warrantee the same as the failing bad caps did.
                            I assume no responsibility for any stupid suggestions I might post.

                            Comment

                            • augiedoggy
                              Senior Member
                              • Aug 2016
                              • 62
                              • united states

                              #15
                              Re: Count of Leds burnt in backlight POLL !?

                              Originally posted by dskall
                              I am modifying the current supplies to the leds on vizio and LG. They run there current at 400ma+ on leds only rated for about 350ma. I want to set them below 350ma. Funny thing is I reduced max. current over 100ma with little noticeable change in brightness. Makes you wonder if it's calculated to kill the tv after warrantee the same as the failing bad caps did.
                              Curious, Will you share how are you modifying them?

                              Comment

                              • dskall
                                Badcaps Legend
                                • Oct 2016
                                • 2905
                                • usa

                                #16
                                Re: Count of Leds burnt in backlight POLL !?

                                Just learning this stuff. Need to modify led controller current sense resistors.
                                https://www.badcaps.net/forum/showthread.php?t=61722
                                I assume no responsibility for any stupid suggestions I might post.

                                Comment

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