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KDL-46v3000 Sony Bravia LCD issues

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    KDL-46v3000 Sony Bravia LCD issues

    Alright I will try to make this quick. First I would like to say that I am new and have read tons of very informative information on the forums here. A ton of great minds here so I am hoping we can all troubleshoot and fix the issues I am having.

    Model: KDL-46v3000 Sony Bravia LCD
    Issues: Black vertical bars mid screen full screen height

    Background: A friend picked this tv up from a local woman he did some work for. He was instructed to take it to the dump. He instead brought it to me in hopes that I could fix it.

    Upon getting the unit I powered it up to see that it was giving me a red blinking led code. 6 blinks which I researched to find was a back light issue. I looked around online and found the service and training manual for this set. After following some voltage checks I was able to determine the issue was with the G1 (power supply) board. I pulled the G1 and to my dismay the board had a rather large crack along the top of the board where the two 450v capacitors fed the H2 and H3 boards (ballancer boards in this unit, normally called an inverters I suppose). Anyhow I cleaned the board up glued it exposed the broken traces, soldered some bridges, and ultimately made some rather extensive jumpers. I then put the power supply back in and was happy to see that I had a working picture. Well kind of. I guess the original issue the set was having was that it was displaying double images and darkness so the owners resulted to hitting the unit in order to "fix" the issue. The issue was still present after fixing the ps G1 board although after heating up for a few minutes the issue seemed to resolve itself. I followed some information found online and decided to troubleshoot the tcon board. It seemed to me that if I powered the unit on cold the issue would occur, however if i pulled one of the two ribbon cables connecting to the lcd boards that the issue would disappear.

    It was during one of these disconnects that some vertical white lines, probably 2-4 pixels wides appeared around 5 pixels to the right of a few of the tabs on the left side of the screen. They were all uniform as in respect to the distance from each tab. I shut the unit down to do some more research and the next time I powered the set up I had a new issue. A HUGE black panel several pixels wide was now running vertically under one of the tabs. That tab is HOT HOT HOT to touch and i believe caused the tcon board to blow the 3a fuse. At this time I have replaced the fuse and found no other issues with the tcon and am hoping to find some direction as to what could be wrong with the culprit tab and if it is able to be repaired.

    How to troubleshoot an ic in a tab? what would make it hot as hell? could there be a short in the bond?

    thanks in advance! this is an awesome place!

    #2
    Re: KDL-46v3000 Sony Bravia LCD issues

    I have had this happen before, and sadly, it means the panel is wrecked. The ICs have tab bond failures due to running so damn hot, but they can also fail on their own -- an internal short can develop on any one of the ~384 output lines which drives the panel. No way to replace that IC on the bond when it's attached to the panel like that.
    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


      #3
      Re: KDL-46v3000 Sony Bravia LCD issues

      so your verdict is that the tab bond has failed or that the ic itself is shot?

      is there a chance that there is a short in the cable from the tcon to the lcd is shorted?

      Comment


        #4
        Re: KDL-46v3000 Sony Bravia LCD issues

        Alright well I believe I found my issue. Sadly it is pretty scary and probably not able to be repaired. One of the tabs running of the lcd board running to the lcd has several bridged exposed contacts. Not sure how the hell it happened but none-the-less it did. I attempted to take a few photos through my microscope to show you all the damage.

        The brown colored ribbon photos are taken from what would be the outside or topside of the ribbon and the green colored ribbon photos are taken from what would be the inside or underside of the ribbon.

        I think I am going to attempt to repair using a conductive pen and an xacto blade.
        Attached Files

        Comment


          #5
          Re: KDL-46v3000 Sony Bravia LCD issues

          My guess would be the ic or the panel shorted over heating the trace.

          Comment


            #6
            Re: KDL-46v3000 Sony Bravia LCD issues

            It does look like burnt traces.
            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


              #7
              Re: KDL-46v3000 Sony Bravia LCD issues

              Okay I have since completely removed the LCD panel and moved it to my work station. After another close inspection with the microscope I have found a grouping of thirteen traces running from the LCD ic to the LCD pcb. Mind you there are probably a 70 or so in total off the IC but the column where my problem is only contains thirteen. Of the thirteen only eleven actually are in use and the other two just run a ways and stop connecting to nothing. Sadly not the traces I have issues with.

              Now the good news. Well kind of. Lol. I currently have six or seven exposed traces however only one is broke and lifted. The others seem to be okay and not shorted to a neighboring trace. My plan is to somehow cover the exposed traces then reconnect the lifted trace and cover it as well.

              I read an interesting post a few days ago at another site avs something rather entitled universal tab repair. In it the poster discussed ways of rebonding panel tabs. My issue isn't where the tab connects to the pcb though as I have now found a few traces in the "tape" that have lifted from the ic or at least appear that way. I can't really ohm them out due to the ic being glued with a silicone of some sort not to mention my fluke doesn't have tips fine enough to touch single pads on a chip that size. Having nothing to loose and everything to gain I decided to use a tunnel type tip on my soldering iron and proceeded to apply a little pressure to the affected area. This does not seem to be doing anything and I have decided the tape that is used to enclose the traces is apparently GMO made from superman's DNA.

              Comment


                #8
                Re: KDL-46v3000 Sony Bravia LCD issues

                well what happened????

                Comment


                  #9
                  Re: KDL-46v3000 Sony Bravia LCD issues

                  Well I believe what happened is that I most probably got the tabs to rejoin however I think the ic itself is shorted somewhere as it instantly would heat to a few hundred degrees. At this point in the game I have sat the unit to the side and plan to sell it off as parts as I know the rest of the parts are tested and working well. I still plan to play with the tab bonds and try to find reasonable repair ideas for them.

                  Comment

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