LG 60PB5600 - No picture

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • mtb604
    Member
    • Jun 2016
    • 39
    • USA

    #41
    Re: LG 60PB5600 - No picture

    So should I just replace those four IGBTs and then reinstall the board and see if it works?

    Comment

    • Hamie
      Badcaps Legend
      • Apr 2014
      • 1383
      • UK

      #42
      Re: LG 60PB5600 - No picture

      Id check to make sure that the short between vs input and ground is gone.

      Comment

      • mtb604
        Member
        • Jun 2016
        • 39
        • USA

        #43
        Re: LG 60PB5600 - No picture

        I tested them off board and on board- no short.
        I installed the board and plugged in the TV and the IGBTs shorted immediately.
        What did I miss?

        Comment

        • mtb604
          Member
          • Jun 2016
          • 39
          • USA

          #44
          Re: LG 60PB5600 - No picture

          Is this a lost cause or should I keep trying to find the fault?
          What do you recommend I try next?

          Comment

          • mtb604
            Member
            • Jun 2016
            • 39
            • USA

            #45
            Re: LG 60PB5600 - No picture

            Might the buffers be shorting out the y-sus board?

            Comment

            • mtb604
              Member
              • Jun 2016
              • 39
              • USA

              #46
              Re: LG 60PB5600 - No picture

              Should I replace the buffers and then replace the IGBTs again?

              Comment

              • Hamie
                Badcaps Legend
                • Apr 2014
                • 1383
                • UK

                #47
                Re: LG 60PB5600 - No picture

                OK let's try again, but this time please don't rush ahead and install boards before its been tested.

                To answer your question this TV does suffer form faulty buffers so it's very possible that the buffers are taking out the sustain board.

                Firstly take a picture of the top side of the y-sustain.

                Comment

                • mtb604
                  Member
                  • Jun 2016
                  • 39
                  • USA

                  #48
                  Re: LG 60PB5600 - No picture

                  Thanks for sticking with me!
                  Here is the top of the Y-Sus board.
                  Attached Files

                  Comment

                  • Hamie
                    Badcaps Legend
                    • Apr 2014
                    • 1383
                    • UK

                    #49
                    Re: LG 60PB5600 - No picture

                    So put your meter in ohm range.

                    And check the resistance between the pins vs and gnd.
                    On this connector here.

                    Black probe ground, Red probe either of the vs pins.

                    Post back your reading.

                    Comment

                    • Hamie
                      Badcaps Legend
                      • Apr 2014
                      • 1383
                      • UK

                      #50
                      Re: LG 60PB5600 - No picture

                      Pic
                      Attached Files

                      Comment

                      • mtb604
                        Member
                        • Jun 2016
                        • 39
                        • USA

                        #51
                        Re: LG 60PB5600 - No picture

                        I got 9 K-ohms across VS and ground at the P130 connector

                        Comment

                        • Hamie
                          Badcaps Legend
                          • Apr 2014
                          • 1383
                          • UK

                          #52
                          Re: LG 60PB5600 - No picture

                          That seems about right.
                          Try running the tv with both the buffers disconnected.

                          Does it stay on?

                          Comment

                          • mtb604
                            Member
                            • Jun 2016
                            • 39
                            • USA

                            #53
                            Re: LG 60PB5600 - No picture

                            No. The four IGBTs I replaced are all shorted so the TV will not stay on with the Y-Sus board connected.

                            Comment

                            • Hamie
                              Badcaps Legend
                              • Apr 2014
                              • 1383
                              • UK

                              #54
                              Re: LG 60PB5600 - No picture

                              in my experience if any of those IGBTs are shorted you shouldnt get anything like 9k ohms between vs and ground. it would be far lower.

                              Comment

                              • mtb604
                                Member
                                • Jun 2016
                                • 39
                                • USA

                                #55
                                Re: LG 60PB5600 - No picture

                                Well, crap. I connected the y-sus board to the P130 connector and the P100 ribbon cable. There were pops and flashes in the vicinity of the IGBTs and smoke from the vicinity of the logic board.

                                After I disconnected the power and waited for the caps to discharge, I measured the resistance across VS and ground at the P130 connector and now I get 0 ohms.

                                Comment

                                • mtb604
                                  Member
                                  • Jun 2016
                                  • 39
                                  • USA

                                  #56
                                  Re: LG 60PB5600 - No picture

                                  Is it beyond repair now?

                                  Comment

                                  • civiliandave
                                    New Member
                                    • Jul 2016
                                    • 3
                                    • United States

                                    #57
                                    Re: LG 60PB5600 - No picture

                                    Not trying to jack your thread, I just have the exact same TV that is power cycling and I'm interested to see how you do. Or maybe one of us will have some parts for the other...

                                    Comment

                                    • mtb604
                                      Member
                                      • Jun 2016
                                      • 39
                                      • USA

                                      #58
                                      Re: LG 60PB5600 - No picture

                                      Hi Civilandave- check the youtube videos on ShopJimmy.com. I seem to remember that issue was addressed in one of their repair videos. If the problem turns out to be a bad y-sus board, I have not been able to find any replacement boards, but ShopJimmy has a repair kit to replace the transistors and resistors if you are comfortable soldering the components.

                                      Comment

                                      • mtb604
                                        Member
                                        • Jun 2016
                                        • 39
                                        • USA

                                        #59
                                        Re: LG 60PB5600 - No picture

                                        So is this still repairable or did I completely fry it this time?

                                        Comment

                                        • mtb604
                                          Member
                                          • Jun 2016
                                          • 39
                                          • USA

                                          #60
                                          Re: LG 60PB5600 - No picture

                                          Is there any way to check the logic board?

                                          Comment

                                          Related Topics

                                          Collapse

                                          Working...