Announcement

Collapse
No announcement yet.

LG 55LW5600 No Video No Sound

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    #21
    Re: LG 55LW5600 No Video No Sound

    Originally posted by budm View Post
    Is it 12 Ohms readings in both directions of the probes?
    When I just read it my meter showed 13.0 with the black probe on pin 1 and 13.6 with the black probe on pin 8.

    Comment


      #22
      Re: LG 55LW5600 No Video No Sound

      Black probe on pin 1, red probe on pin 8 = ?? Ohms.
      Red probe on pin 1, black probe on pin 8 = ?? Ohms
      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


        #23
        Re: LG 55LW5600 No Video No Sound

        Originally posted by budm View Post
        Black probe on pin 1, red probe on pin 8 = 13.0 Ohms.
        Red probe on pin 1, black probe on pin 8 = 13.6 Ohms
        Added the numbers in the quote.

        Comment


          #24
          Re: LG 55LW5600 No Video No Sound

          That is not normal to me, it should be in 100's or 1000's Ohms range.
          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


            #25
            Re: LG 55LW5600 No Video No Sound

            That's with the TV unplugged. It was higher when it was plugged in (but off).

            Comment


              #26
              Re: LG 55LW5600 No Video No Sound

              Is it safe to say the main board is the problem? I'd be willing to replace that (if I can find one) to get this back up and running.

              Comment


                #27
                Re: LG 55LW5600 No Video No Sound

                Being able to turn the TV on and off but with no picture, no sound, and no backlight is a very common issue we see from these TVs and it is caused by a bad main board. The BGA chip which is located underneath the large heatsing, is no communicating with the board properly. Generally performing a reflow or reball of this module will take care of your failure.
                You most likely won't find a board for sale as these are discontinued and no longer in stock.
                You will however find that a few different companies do offer mail in repair services on such modules. Be careful of eBay repair services however as you may notice all of them have no warranties on the repairs or only a 30-60 day warranty. Most eBay sellers with such short warranty periods are set up that way due to the fact that they do not perform a proper repair and usually repeat failures will occur within 6 months of the repair. If you do send in your module, make sure to find a service that offers an extended warranty such as a full 1 year warranty.
                A link to a service listing is below:

                http://www.nickstvs.com/store/p1425/EBT61398005

                good luck

                Comment


                  #28
                  Re: LG 55LW5600 No Video No Sound

                  Could you post a picture of IC505 and the area around it. As well focussed as possible.
                  Willing to help but I'm no expert.

                  Comment


                    #29
                    Re: LG 55LW5600 No Video No Sound

                    The AOZ1024D can supply an output current of 4 Amp continuous according to the data sheet. If the resistance at pin 8 is 13 ohms then at 3.3v out would be a current flowing of 253mA.
                    The AOZ1021 can provide a continuous output current of 3 Amps. I think the IC or the components around the IC is faulty.
                    Attached Files
                    Last edited by dick_barton; 07-31-2018, 04:37 AM.
                    Willing to help but I'm no expert.

                    Comment


                      #30
                      Re: LG 55LW5600 No Video No Sound

                      Try to reflow or reball the main procecor in the mainboard.

                      Comment


                        #31
                        Re: LG 55LW5600 No Video No Sound

                        Originally posted by DIMITRIO View Post
                        Try to reflow or reball the main procecor in the mainboard.
                        As mentioned in the original post, I did the heatgun method and oven method to try and reflow the board initially with no success. What is the best method to do this? I followed advice from a few different sources I found around on the interwebz. Like for the oven - what temp and for how long? The heatgun really made me kind of nervous.

                        Comment


                          #32
                          Re: LG 55LW5600 No Video No Sound

                          Originally posted by dick_barton View Post
                          The AOZ1024D can supply an output current of 4 Amp continuous according to the data sheet. If the resistance at pin 8 is 13 ohms then at 3.3v out would be a current flowing of 253mA.
                          The AOZ1021 can provide a continuous output current of 3 Amps. I think the IC or the components around the IC is faulty.
                          I verified the number. It is correct. Both of those numbers are printed on the top of IC505 (one above the other). Z1024DI/ZA1012. I'll try and get a pic when my wife gets home. I don't think I have a camera that will get a very close and detailed pic.
                          Last edited by mtskibum16; 07-31-2018, 06:50 PM.

                          Comment


                            #33
                            Re: LG 55LW5600 No Video No Sound

                            Originally posted by dick_barton View Post
                            Could you post a picture of IC505 and the area around it. As well focussed as possible.
                            This is the best I could do. Do you need more of the area or is that good? FYI pin1 looks more like pin 8 than the picture shows. I think that's mainly light pollution making pin 1 look blown out.
                            Attached Files
                            Last edited by mtskibum16; 07-31-2018, 10:44 PM.

                            Comment


                              #34
                              Re: LG 55LW5600 No Video No Sound

                              Pin 7 & 8 connect to the coil. Does the other side of the coil connect to a ceramic capacitor?
                              Willing to help but I'm no expert.

                              Comment


                                #35
                                Re: LG 55LW5600 No Video No Sound

                                Originally posted by dick_barton View Post
                                Pin 7 & 8 connect to the coil. Does the other side of the coil connect to a ceramic capacitor?
                                Here's a pic.
                                Attached Files

                                Comment


                                  #36
                                  Re: LG 55LW5600 No Video No Sound

                                  Might wanna check the power supply because I have seen them fail in these models. Check the secondary fuse, the mosfets and also inspect the blue ceramic capacitor near the mosfets.

                                  Comment


                                    #37
                                    Re: LG 55LW5600 No Video No Sound

                                    I think that IC505 is faulty. It creates the 3.3V_Normal supply from the 12V input to run so many other parts of the set as shown on page 104.
                                    Last edited by dick_barton; 08-02-2018, 03:52 AM.
                                    Willing to help but I'm no expert.

                                    Comment


                                      #38
                                      Re: LG 55LW5600 No Video No Sound

                                      i have same tv...no picture using flashlight test

                                      ..i have no voltage at the fuse on the tcon

                                      all voltages from ps seem good 3.3v 12v 24v
                                      all voltages to leds seem good 56v and 56v

                                      any ideas?

                                      Comment


                                        #39
                                        Re: LG 55LW5600 No Video No Sound

                                        Late to join this discussion, but my TV just failed. This case is almost identical in part to mine. I also measure ~13 ohms from 0.9_core rail to ground. I also measure the same ~12-13 ohms from 3.3V_norm rail to ground. Replaced IC505 no luck.
                                        All connections between the two are through at least two resistors. Another common point is the main controller. Any other ideas? Thanks you

                                        Comment


                                          #40
                                          Re: LG 55LW5600 No Video No Sound

                                          55LW5600
                                          seems to be common main board GPU issue
                                          if you use a heat gun to heat up the GPU it may get tv to power on ok

                                          i did it and it worked

                                          obviously this may or may not be a perm fix

                                          it is a main board issue and since the main board for this tv is so costly its not worth replacing

                                          Comment

                                          Working...
                                          X