LG 42LG3000 Backlight for 2 sec

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  • Parre
    New Member
    • Feb 2013
    • 1
    • Sweden
    #1

    LG 42LG3000 Backlight for 2 sec

    Hi.

    I have been reading a whole bunch of thread here on Badcaps.com about tv repairs but i just can't find the fault on my LG.
    When i turn the tv on it starts as expected by showing the channel number in the upper right corner but about 1 or 2 seconds later the backlight fades and it turns black. By pointing a flashlight at the screen i can still see the channel number.

    I have desoldered every single capacitor and meassured capacitance but not the ESR as i do not have the right equipment. The caps seems to be fine though with the right capacitance and no visual error.

    I have resoldered some bad solder points on the blacklight inverters as well with no success.

    I may try to buy new caps and replace them all but i am hoping that you might have some tips on how to solve this.

    I attached a few pictures to show the boards and a video to show how the tv behaves. http://youtu.be/buCtI47IUzc




    Tags: None
    • Alessio
      New Member
      • Mar 2013
      • 6
      • iTALIA
      #2
      Re: LG 42LG3000 Backlight for 2 sec

      Same here

        Comment

        • richpart
          Member
          • May 2012
          • 42
          • USA
          #3
          Re: LG 42LG3000 Backlight for 2 sec

          I have a stupid question? Did you try to update the firmware yet? (Version_03.55.01)

          Available here http://www.lg.com/ie/support/product...initialTab=faq

          Service manual trouble shooting section states as follows:
          This board has big problem because
          Main IC(IC100) have some troubles.
          After checking thoroughly all path once
          again, You should decide to replace
          Main Board or not.

            Comment

            • tom66
              EVs Rule
              • Apr 2011
              • 32560
              • UK
              #4
              Re: LG 42LG3000 Backlight for 2 sec

              This is probably 2 seconds to black, so check the BLON signal on mainboard to see if it is main board or inverter/PSU/bulbs.
              Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
              For service manual, schematic, boardview (board view), datasheet, cad - use our search.

                Comment

                • apocalip
                  New Member
                  • Sep 2013
                  • 2
                  • Germany
                  #5
                  Re: LG 42LG3000 Backlight for 2 sec

                  tom66: could you please describe how to check the BLON?

                    Comment

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