LG 47LS4500 backlight and sound, but no display

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  • godzfire
    Member
    • Dec 2017
    • 16
    • USA

    #1

    LG 47LS4500 backlight and sound, but no display

    Hello everyone. Looking to hopefully get some thoughts and guidance on my beloved LG 47LS4500 TV, purchased in Feb '13.

    One day I turned it on, and all I got was a slightly white backlight display. Thinking a cable was loose or something, I checked all connections and verified also it wasn't the wrong source being chosen. The sound works just fine, the LED power light is active and responds to all remote and on-tv commands, and when I plug in a video cord to my computer, the computer recognizes the display as being attached.

    I attempted to contact LG Repair who pointed me to a small local TV repair shop. When I called, they stated it would cost a fair amount just to look at the display.

    I'm just hoping the knowledgeable folks here might have some ideas what could be going on/issue might be, and if there's any chance it's worth bringing it in. I deal with bad anxiety which can make making decisions very difficult, especially when it deals with a large monetary item, so I really appreciate everyone's educated assistance in this matter. Thank you all in advance.


  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: LG 47LS4500 backlight and sound, but no display

    We need to pictures of the whole backside of the TV showing all the board.
    At this point you need to find out if you are getting the 12VDC at both end of the SMD fuse on the T-CON board or not.
    You do have meter and know how to use it, right?
    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

    • godzfire
      Member
      • Dec 2017
      • 16
      • USA

      #3
      Re: LG 47LS4500 backlight and sound, but no display

      Hello budm, thanks for the message. No, sorry I am not familiar with any of that. I wouldn't mind taking off the back panel and taking some pictures if that would help. One of my friends deal with electronics and might have that, what equipment specifically should I be looking for?

      Comment

      • budm
        Badcaps Legend
        • Feb 2010
        • 40746
        • USA

        #4
        Re: LG 47LS4500 backlight and sound, but no display

        You cannot do much without the meter, but still need to see the pictures to see if the T-CON is integrated with the LCD panel or not.
        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

        • godzfire
          Member
          • Dec 2017
          • 16
          • USA

          #5
          Re: LG 47LS4500 backlight and sound, but no display

          Here's some additional pictures. Let me know if you want any close up pictures on anything:











          Comment

          • JT Morgan
            New Member
            • Dec 2017
            • 1
            • US

            #6
            Re: LG 47LS4500 backlight and sound, but no display

            I have this exact same issue. Same manufacturer date and location as well. Think this is coincidental? Just happened.

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: LG 47LS4500 backlight and sound, but no display

              So did you get the meter yet?
              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

              • godzfire
                Member
                • Dec 2017
                • 16
                • USA

                #8
                Re: LG 47LS4500 backlight and sound, but no display

                Hey Bud, sorry for not responding back sooner, didn't get a notification you replied. I am still trying to track down someone who has a voltage meter. Is there anything you can see from the pictures or things I can check in terms of damage or what not?

                Comment

                • budm
                  Badcaps Legend
                  • Feb 2010
                  • 40746
                  • USA

                  #9
                  Re: LG 47LS4500 backlight and sound, but no display

                  Nope.
                  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

                  • godzfire
                    Member
                    • Dec 2017
                    • 16
                    • USA

                    #10
                    Re: LG 47LS4500 backlight and sound, but no display

                    Okay I have one of these guys to hopefully help me, if someone could tell me what I need to do/test:

                    Comment

                    • budm
                      Badcaps Legend
                      • Feb 2010
                      • 40746
                      • USA

                      #11
                      Re: LG 47LS4500 backlight and sound, but no display

                      http://en-us.fluke.com/products/elec...html#techspecs
                      http://en-us.fluke.com/products/elec...al-tester.html

                      Are you joking?
                      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

                      • godzfire
                        Member
                        • Dec 2017
                        • 16
                        • USA

                        #12
                        Re: LG 47LS4500 backlight and sound, but no display

                        I'm sorry like I said I am not familiar with any of this and reaching out for help. Can you show me a picture of what meter you are talking about and provide some links?

                        Comment

                        • freakaftr8
                          Badcaps Legend
                          • Oct 2012
                          • 3743
                          • USA

                          #13
                          Re: LG 47LS4500 backlight and sound, but no display

                          We need to see if your tcon is getting 12v or not. Also need to do some fuse checks. With your meter, what happens when you touch the 2 probes together ?
                          Did I leave the soldering iron on?

                          Comment

                          • godzfire
                            Member
                            • Dec 2017
                            • 16
                            • USA

                            #14
                            Re: LG 47LS4500 backlight and sound, but no display

                            Hello freak, thanks for replying. If you mean touching the red and black ends from the Fluke meter together it makes a continuous beep.

                            If you can tell me or highlight on my pictures where I need to put the testing ends on which parts I will do it.

                            Comment

                            • freakaftr8
                              Badcaps Legend
                              • Oct 2012
                              • 3743
                              • USA

                              #15
                              Re: LG 47LS4500 backlight and sound, but no display

                              You will have to remove that cover on the bottom middle board and look for a fuse labeled F something. Fuse will be located where the flat ribbon cable plugs into the tcon board. This will be the board that we're focusing on right now

                              Also I noticed the screen on your fluke meter has a pressure point does it still show a display?
                              Last edited by freakaftr8; 12-30-2017, 03:21 PM.
                              Did I leave the soldering iron on?

                              Comment

                              • godzfire
                                Member
                                • Dec 2017
                                • 16
                                • USA

                                #16
                                Re: LG 47LS4500 backlight and sound, but no display

                                Okay here's what I see:



                                EDIT: Yes the meter display does work and the meter itself functions fine. Tested it on some items at work.
                                Last edited by godzfire; 12-30-2017, 03:28 PM.

                                Comment

                                • budm
                                  Badcaps Legend
                                  • Feb 2010
                                  • 40746
                                  • USA

                                  #17
                                  Re: LG 47LS4500 backlight and sound, but no display

                                  Check the resistance of that white fuse right next to the left side of the top connector.
                                  NO POWER to the TV!
                                  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

                                  • freakaftr8
                                    Badcaps Legend
                                    • Oct 2012
                                    • 3743
                                    • USA

                                    #18
                                    Re: LG 47LS4500 backlight and sound, but no display

                                    Use your red and black probe on each side that fuse with the TV unplugged
                                    Did I leave the soldering iron on?

                                    Comment

                                    • godzfire
                                      Member
                                      • Dec 2017
                                      • 16
                                      • USA

                                      #19
                                      Re: LG 47LS4500 backlight and sound, but no display

                                      Okay can do, just need to know where to properly place the red and black probes to properly check.

                                      EDIT: Guessing you mean putting one on each of the gold ends. Did that, and no beep. However, if I place each of the probes on both sides of each of the single gold ends, it does beep.
                                      Last edited by godzfire; 12-30-2017, 03:36 PM.

                                      Comment

                                      • freakaftr8
                                        Badcaps Legend
                                        • Oct 2012
                                        • 3743
                                        • USA

                                        #20
                                        Re: LG 47LS4500 backlight and sound, but no display

                                        Ok...

                                        Well the fuse is bad. There's your problem. Either find a way to replace fuse Or replace the board by the part number on the board
                                        Did I leave the soldering iron on?

                                        Comment

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