LG 32LB5800 No Backlight

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  • tech2014
    Badcaps Veteran
    • Aug 2014
    • 807
    • Canada
    #1

    LG 32LB5800 No Backlight

    I have a 32" LG LED TV with no backlight. I see the video is present when the menu button is pressed. The backlight doesn't come on at all. I get all of my voltages. The connector from the LED panel to the power supply board, I get 144Volts on the far left pin, which is LED+. I get 0V on all the other pins.

    The filter caps in pic 1, Should I not get 165v in standby and about 360V in full on mode. I only get 165V both ways. If so, this would be a PFC circuit problem?



    Attached Files
    Last edited by tech2014; 12-28-2015, 02:55 PM.
    Tags: None
    • ReeceyBurger123
      Never Give Up !
      • May 2014
      • 7325
      • Britain
      #2
      Re: LG 32LB5800 No Backlight

      You have a open or shorted Led with in the Lcd module, tear it apart being very careful of the Lcd screen and get some images.
      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

        • tech2014
          Badcaps Veteran
          • Aug 2014
          • 807
          • Canada
          #3
          Re: LG 32LB5800 No Backlight

          Will do that, thanks!!!

            Comment

            • ReeceyBurger123
              Never Give Up !
              • May 2014
              • 7325
              • Britain
              #4
              Re: LG 32LB5800 No Backlight

              No worries buddy
              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

                • tech2014
                  Badcaps Veteran
                  • Aug 2014
                  • 807
                  • Canada
                  #5
                  Re: LG 32LB5800 No Backlight

                  I got everything removed and have access to the LED strips. I measured and there is 1 shorted LED on B LED string and 2 on the bottom A string. These things are expensive to replace. Is it worth fixing?



                  Attached Files
                  Last edited by tech2014; 12-28-2015, 04:06 PM.

                    Comment

                    • ReeceyBurger123
                      Never Give Up !
                      • May 2014
                      • 7325
                      • Britain
                      #6
                      Re: LG 32LB5800 No Backlight

                      Do you have any smashed Led Tvs ?
                      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

                        • ReeceyBurger123
                          Never Give Up !
                          • May 2014
                          • 7325
                          • Britain
                          #7
                          Re: LG 32LB5800 No Backlight

                          If so you can take the Leds off them and reuse them, if not you can substitute the leds with a zener diode or resistor.
                          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

                            • abdekader
                              Senior Member
                              • Jul 2014
                              • 73
                              • Turkey
                              #8
                              Re: LG 32LB5800 No Backlight

                              problem with backlight
                              Electronic Engineer from Syria,Aleppo

                                Comment

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