lg 47le5400 powers up, black screen, no sound

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #21
    Re: lg 47le5400 powers up, black screen, no sound

    You count the pins wrong, please upload good clear pictures of the connector and the pin labels as printed on the board, it helps to show pictures of your power supply board since there are more than one version of the boards used in this TV model.
    https://www.shopjimmy.com/catalogsea...?q=lg+47le5400
    The connector has odd column number pins and even column number pins.
    Last edited by budm; 12-28-2018, 03:07 AM.
    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

    • maxim22
      New Member
      • Oct 2013
      • 5
      • Canada

      #22
      Re: lg 47le5400 powers up, black screen, no sound

      Originally posted by maxim22
      In PowerOn mode all voltages seem to be OK except PowerOn voltage (pin 1) which is 3.23V instead of 20V (as written on the board).
      In StandBy mode there is only 3.4 V on 2 pins (pin5,6), all others are 0V.
      I got a light on the screen by 2 jumpers from 3.4 V pins to Drv ON and Power On pins. Previously disconnected power connector on the main board as visible on the picture.
      Another picture shows voltages on the connector.
      Attached Files
      Last edited by maxim22; 12-28-2018, 01:56 PM.

      Comment

      • maxim22
        New Member
        • Oct 2013
        • 5
        • Canada

        #23
        Re: lg 47le5400 powers up, black screen, no sound

        There is also 12.5 V on pins 2,3,4 in the 2nd row from top.

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #24
          Re: lg 47le5400 powers up, black screen, no sound

          The exposed pins you see on the top side of the board are the odd number pins, pin 1 is marked with black arrow, the even number pins you you have to probe from the bottom side of the board or from the backside of the female connector.
          So if you have all connector in place but you do not have DRV-ON which is from the main board then you need to troubleshoot the main board next.
          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

          • maxim22
            New Member
            • Oct 2013
            • 5
            • Canada

            #25
            Re: lg 47le5400 powers up, black screen, no sound

            Originally posted by budm
            The exposed pins you see on the top side of the board are the odd number pins, pin 1 is marked with black arrow, the even number pins you you have to probe from the bottom side of the board or from the backside of the female connector.
            So if you have all connector in place but you do not have DRV-ON which is from the main board then you need to troubleshoot the main board next.
            The picture with voltages is actually the bottom of the connector. Do you have any tips for the main board? I tried heating the board at 385F in the oven but no luck.
            Last edited by maxim22; 12-28-2018, 04:50 PM.

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #26
              Re: lg 47le5400 powers up, black screen, no sound

              What you can do to see if other function of the main board, T-CON board, LCD panel are OK or not is to put all the connectors back in place then disconnect the DRV wire going back to the main board and then force on the backlights and see if you will get pictures on the screen, sound, and all the function or not, if not then you have more than just bad DRV control signal.
              More likely the MCU needs to be reballed, baking in the oven may or may not work and it is usually go bad again.
              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

              • diif
                Badcaps Legend
                • Feb 2014
                • 6978
                • England

                #27
                Re: lg 47le5400 powers up, black screen, no sound

                Originally posted by Jov4e@lazarev
                Hi I HAVE THE SAME PROBLEM TV TURNS ON BUT NO BACKLIGHT NO PICTURE NO SOUND.I BAKING THE MAIN BOARD IN THE OVEN 200C ON 10 MINUTES BUT NO RESULTS.TV MODEL LG 42LE5500
                It's not a cake, there is no baking involved, you are trying to get the solder balls under the processor to remelt and remake any broken solder connections.
                Lead free solder melts at around 220c.

                Comment

                • tvtimmy
                  Badcaps Legend
                  • Mar 2015
                  • 1160
                  • usa

                  #28
                  Re: lg 47le5400 powers up, black screen, no sound

                  That around 428° farenheit. That temp will melt every plastic piece and cause most capacitors to explode.

                  Comment

                  • diif
                    Badcaps Legend
                    • Feb 2014
                    • 6978
                    • England

                    #29
                    Re: lg 47le5400 powers up, black screen, no sound

                    Originally posted by tvtimmy
                    That around 428° farenheit. That temp will melt every plastic piece and cause most capacitors to explode.
                    Probably, I wouldn't know having a BGA rework machine and only knowing centigrade.
                    The point I was trying to make is that baking at 200c/385f is kinda pointless.

                    Comment

                    • nomoresonys
                      Badcaps Legend
                      • Jan 2013
                      • 12074
                      • U.S.

                      #30
                      Re: lg 47le5400 powers up, black screen, no sound

                      Only a temporary fix if successful, trick is to melt the solder under the chip, OVERHEATING can kill the chip, lots of videos on youtube, one guy uses an old repurposed halogen floor lamp.
                      Last edited by nomoresonys; 06-07-2019, 07:43 AM.

                      Comment

                      • diif
                        Badcaps Legend
                        • Feb 2014
                        • 6978
                        • England

                        #31
                        Re: lg 47le5400 powers up, black screen, no sound

                        Originally posted by Jov4e@lazarev
                        I watch some videos on YouTube they put the motherboard in the oven because Im not professionalI think that will help but nothing can I try with with hair dryer I dont have heat gun
                        If it gets hot enough yes a hair dryer can be used. I have also seen examples where a tea light candle was used.

                        https://www.geektechnique.org/projec...rd-repair.html
                        https://www.overclock.net/forum/69-n...-tealight.html

                        Probably safer than heating the whole board in the oven to 220c.

                        Perhaps it would be worth investing in a cheap thermometer/thermocouple so you know the correct temperature has been reached. Also don't forget flux.

                        Comment

                        Related Topics

                        Collapse

                        • Mgiffune
                          Samsung UN60EH6000F Black Screen, Backlight and Sound Good. Power Cycle Returns Picture
                          by Mgiffune
                          I have a 60 inch Samsung UN60EH6000F flatscreen TV. The screen went black a few months ago Sound is good, backlight is good, no menu. I replaced the TCon board with a used board purchased from Ebay. It worked fine for a 3-4 months, then the screen started ‘fading' back. Once again, sound is good, backlight is good, no menu. However, this time the picture looks fine for about 10-15 minutes, then fades back. If I power cycle the TV, the display reappears, for another 10-15 minutes, then fades black again. Repeatable ever time.

                          I ordered a supposedly ‘new' Tcon board this time, and
                          ...
                          06-09-2024, 10:28 AM
                        • Audeze
                          Sony XBR-75X950G seems dead with a black screen but backlight and sound is working and no blinking red lights
                          by Audeze
                          I have a 2019 75" x950g, and while playing a movie, the screen suddenly went dark in a weird way, where it faded towards one corner into being fully black. Now the TV turns on, and the backlight comes on, but there is nothing displayed except black. Sound still comes through the TV speakers, and i have tried doing a hard reset using the volume - and power buttons while plugging the display back in, but it did not fix it. I can confirm that pressing buttons on my remote is still doing "something" because I'm hearing sound still, even though the screen is black.

                          Does...
                          10-06-2024, 08:54 PM
                        • HTR-Informatique
                          Dell G3 15 3500 - Battery bug (black screen and flashing keyboard backlight)
                          by HTR-Informatique
                          Hello,

                          YouTube video of the problem encountered: https://youtube.com/shorts/q7TLNv36LUo

                          I am a pro and I have a problem that I have never seen despite my 7.5 years of experience on my own and my thousands of repairs, on a customer's Dell G3 15 3500.

                          On this PC I have already changed the complete palmrest because the keyboard was no longer working properly.

                          I also changed the screen because the PC fell and the screen was broken.

                          I changed the battery with a new and original battery.

                          I also had corrosion/oxidation on the...
                          02-09-2025, 06:51 AM
                        • totof
                          LG 43UF640V backlight good but black screen and no sound
                          by totof
                          Good morning.
                          I have a problem with my LG Smart 43UF640V TV. It starts, the backlight comes on but nothing is displayed on the screen and there is no sound.
                          I thought it was a TCon problem and ran various tests. If I disconnect one or the other of the cables from the tcon to the panel then the screen is white on the side where the cable is disconnected and black on the other side. If the two cables are disconnected the screen is completely black.
                          In the 4 configurations I measure exactly the same voltages on the tcon card (model V15 43UHD TM120 Ver0.4) :

                          HVDD : 7,28...
                          04-13-2024, 11:37 PM
                        • Rozp
                          70LE660U dark cloud or black screen with sound.
                          by Rozp
                          Hello Everyone,

                          This is my first post so I will try to be as precise as possible without making this post too long winded. Unfortunately I don't have pictures of the original problem but I included images of the TV internals.

                          I have a Sharp 70LE660U. The problem started a few months ago with the bottom row looking out of sync and was dark on the left side and then fading to transparent on the right side. Shortly after, a dark cloud appeared in the center of the screen. The dark cloud started small and shaded but the image was visible. It also affected the menu area....
                          08-29-2023, 05:25 PM
                        • Loading...
                        • No more items.
                        Working...