LG 42PQ20 No Standby Voltage

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  • kmoonen
    Senior Member
    • Dec 2011
    • 61

    #1

    LG 42PQ20 No Standby Voltage

    Hi Everyone

    I have a LG 42PQ20 with no standby voltage, obviously a power supply problem, but i am having trouble narrowing it down , anyone have a similar issue with the power supply (3PAGC00001A-R)

    Ken
  • newtothis
    Badcaps Legend
    • Mar 2013
    • 1556
    • england

    #2
    Re: LG 42PQ20 No Standby Voltage

    Voltage at primary filter cap?

    Comment

    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK

      #3
      Re: LG 42PQ20 No Standby Voltage

      Input fuse good? Pictures of board?
      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

      • kmoonen
        Senior Member
        • Dec 2011
        • 61

        #4
        Re: LG 42PQ20 No Standby Voltage

        Both fuses are ok.. here is a picture

        Attached Files

        Comment

        • newtothis
          Badcaps Legend
          • Mar 2013
          • 1556
          • england

          #5
          Re: LG 42PQ20 No Standby Voltage

          Whats the voltage at primary cap?

          Comment

          • tom66
            EVs Rule
            • Apr 2011
            • 32560
            • UK

            #6
            Re: LG 42PQ20 No Standby Voltage

            Pretty common fault with these is IC301.
            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

            • kmoonen
              Senior Member
              • Dec 2011
              • 61

              #7
              Re: LG 42PQ20 No Standby Voltage

              Ok, im not seeing IC301 on the board

              Comment

              • newtothis
                Badcaps Legend
                • Mar 2013
                • 1556
                • england

                #8
                Re: LG 42PQ20 No Standby Voltage

                Check on the heatsinks

                Comment

                • kmoonen
                  Senior Member
                  • Dec 2011
                  • 61

                  #9
                  Re: LG 42PQ20 No Standby Voltage

                  Found it, Checked it and it is bad

                  any sources online to purchase?.

                  Comment

                  • kmoonen
                    Senior Member
                    • Dec 2011
                    • 61

                    #10
                    Re: LG 42PQ20 No Standby Voltage

                    Does anyone know where i can purchase one of these ?

                    Comment

                    • kmoonen
                      Senior Member
                      • Dec 2011
                      • 61

                      #11
                      Re: LG 42PQ20 No Standby Voltage

                      Ok I have replaced IC301 - STR-W6252. I have 2 more components that are short, R305, and ZD303, does anyone know the values of these 2 components

                      Comment

                      • kmoonen
                        Senior Member
                        • Dec 2011
                        • 61

                        #12
                        Re: LG 42PQ20 No Standby Voltage

                        Resolved.

                        Replaced IC301, R305, ZD303, D305, C307.

                        Comment

                        • TomasNM
                          New Member
                          • Jan 2015
                          • 1
                          • Slovakia

                          #13
                          Re: LG 42PQ20 No Standby Voltage

                          Hello.
                          I have the same problem.
                          Can you please provide the values of additional components,those you've replaced?
                          Thank you,Tomas.

                          Comment

                          • abdekader
                            Senior Member
                            • Jul 2014
                            • 73
                            • Turkey

                            #14
                            Re: LG 42PQ20 No Standby Voltage

                            check these components

                            F301
                            F302
                            IC301
                            R305
                            ZD303
                            D305
                            C307 (33u or 100 u)
                            Electronic Engineer from Syria,Aleppo

                            Comment

                            • Flubbah
                              New Member
                              • Jun 2015
                              • 1
                              • Canada

                              #15
                              Re: LG 42PQ20 No Standby Voltage

                              I have the same problem with the same parts needing replacement.

                              I am not abale to track down a parts list of the components that I need to order.

                              Can anyone help me out ?

                              Comment

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