LG 42LG30 - Another backlight question, but I've read the others :)

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  • DLinkOZ
    Badcaps Veteran
    • May 2013
    • 238
    • USA
    #1

    LG 42LG30 - Another backlight question, but I've read the others :)

    Grabbed this as a cheap TV for the game room. My symptoms are very similar to this thread:

    https://www.badcaps.net/forum/showthread.php?t=20203

    I have the same transformer readings, and my fets all seem good. Additionally, if I unplug the output cable from either inverter (disconnect from the ccfls) the TV will power on and stay on, but with no backlight (obviously). If I leave them connected, it power cycles.

    It *seems* as though the inverters are good, and I need to inspect the ccfls themselves. Is there a service manual or nugget of wisdom for the easiest path to them? Normally a full tear down would be easy enough, however the TV needs to power on with the lamps exposed to give a proper visual.

    Input is greatly appreciated!
    Tags: None
    • nomoresonys
      Badcaps Legend
      • Jan 2013
      • 12206
      • U.S.
      #2
      Re: LG 42LG30 - Another backlight question, but I've read the others

      not sure, maybe a fault coming from inverter/s is causing it to go into protection mode.
      Quit because THIS SITE LETS A ROGUE MEMBER TYPE ANY GARBAGE HE PLEASES AND THE POWERS THAT BE NEVER DO ANYTHING ABOUT IT SO HE NEVER QUITS. THEN YOU GET A PENALTY FOR RESPONDING TO HIS ATTACKS. BEEN GOING ON FOR WAY TOO LONG. DONE SUPPORTING A SITE THAT ALLOWS THIS BS.

        Comment

        • DLinkOZ
          Badcaps Veteran
          • May 2013
          • 238
          • USA
          #3
          Re: LG 42LG30 - Another backlight question, but I've read the others

          I was originally expecting that, but I can unplug either the master or the slave from the ccfl plug and get it stay on. I may be misreading the result, that to me points towards the bulbs.

          **EDIT**
          To clarify, when I unplug the output to the bulbs I leave both inverters connected and powered on. And I only have to unplug *one* of the outputs - either the master or the slave, either one alone will allow it to stay on.
          Last edited by DLinkOZ; 01-16-2015, 03:42 PM. Reason: clarification

            Comment

            • DLinkOZ
              Badcaps Veteran
              • May 2013
              • 238
              • USA
              #4
              Re: LG 42LG30 - Another backlight question, but I've read the others

              I got a quick peek under the panel, and I can't see any dark spots. The bulbs look good. so it may be as simple as a set of inverters (for the price, I might as well grab both).
              Attached Files

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                • nomoresonys
                  Badcaps Legend
                  • Jan 2013
                  • 12206
                  • U.S.
                  #5
                  Re: LG 42LG30 - Another backlight question, but I've read the others

                  Originally posted by DLinkOZ
                  I got a quick peek under the panel, and I can't see any dark spots. The bulbs look good. so it may be as simple as a set of inverters (for the price, I might as well grab both).
                  well if you get some in working order, at least that should rule them out as the problem, please keep us updated.
                  Quit because THIS SITE LETS A ROGUE MEMBER TYPE ANY GARBAGE HE PLEASES AND THE POWERS THAT BE NEVER DO ANYTHING ABOUT IT SO HE NEVER QUITS. THEN YOU GET A PENALTY FOR RESPONDING TO HIS ATTACKS. BEEN GOING ON FOR WAY TOO LONG. DONE SUPPORTING A SITE THAT ALLOWS THIS BS.

                    Comment

                    • DLinkOZ
                      Badcaps Veteran
                      • May 2013
                      • 238
                      • USA
                      #6
                      Re: LG 42LG30 - Another backlight question, but I've read the others

                      Replacement inverters did the trick. This is going with another 42" I have in my game room. Opposite corners connected to an xbox 360 kiosk. My game room is also my arcade

                        Comment

                        • budm
                          Badcaps Legend
                          • Feb 2010
                          • 40746
                          • USA
                          #7
                          Re: LG 42LG30 - Another backlight question, but I've read the others

                          Thanks for the follow-up.
                          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

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