Announcement

Collapse
No announcement yet.

Samsung LN32C540 won't turn on

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

    Samsung LN32C540 won't turn on

    I have picked up this TV last night, so I haven't measured much.
    It seems like it has a pretty common issue, but I'm not sure if it's a simple mainboard swap or there other things that I could do with it?
    Basically looks completely dead and if I unplug the cable between the PS and mainboard I have backlight. If I plug it back it the backlight turns off.
    Most likely the mainboard is not sending the PS_ON signal. I'm thinking of removing/cutting that wire and apply it from outside, to see what happens.
    It also could be a short on the mainboard.
    Any input would be appreciated.

    #2
    Re: Samsung LN32C540 won't turn on

    You are correct, the main board is not sending out the PS_ON to the power supply. The newer Samsung makes it easy to find out if the power supply is good or bad by disconnecting the cable between the main and the power supply board, if the backlights come on, the inverter and the power supply is working. Samsung uses pull up resistor on the power supply board to force on the power supply, the main board keep this line low when TV is off and let the PS_ON to go high when TV is on. Check the voltage regulators and voltages on the main board.
    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


      #3
      Re: Samsung LN32C540 won't turn on

      I have pulled out the PS_ON wire from the connector and all the voltages look good, on the connector and at the VDOs. With the wire connected, there are no voltages at the connector(I have checked only one row, since I couldn't get to the second row) or VDOs.
      The voltage at the PS_ON is 0.022 V only.

      Comment


        #4
        Re: Samsung LN32C540 won't turn on

        So when the PS_ON wire is disconnected, you should see 3V or so at the PS_ON pin of the power supply board. The PS_ON pin on the main board will about nothing.
        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


          #5
          Re: Samsung LN32C540 won't turn on

          Nothing happens even if I apply outside 3.3 V.
          Sorry, I didn't understand the last sentence.

          Comment


            #6
            Re: Samsung LN32C540 won't turn on

            OK, when the PS_ON is disconnected, do the backlights turn on?
            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: Samsung LN32C540 won't turn on

              No. It blinks when I plug in the power cord, or when I pull the cord.

              Comment


                #8
                Re: Samsung LN32C540 won't turn on

                So right now main board is bad since the PS_ON stuck LOW and more likely the same for the BL_0N, the BL_0N pin on the power supply also has built-in pull up resistor, if you remove the BL_ON pin, the backlights should then turn on and stay on. If the Dimming control is PWM type, that line will have to be removed also.
                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


                  #9
                  Re: Samsung LN32C540 won't turn on

                  Thanks. I will try both of them.
                  The problem is, that I can't find another board.
                  I read in another post that it's possible to use othe mainboards, even upgrade to a 550 model.

                  Comment


                    #10
                    Re: Samsung LN32C540 won't turn on

                    I ended up replacing the mainboard which I could not find.
                    I have used shopjimmy compatibility list, and I had only one match from a long list.
                    The original part number(sticker) it was BN96-14763A V1007.0 and the "new" one is BN96-14917A V1003.1.
                    It worked right away, but I have flashed it with the latest firmware and it's all good.
                    The problem is that I have spent to much on this one and won't make much money on it.

                    Comment


                      #11
                      Re: Samsung LN32C540 won't turn on

                      Thanks for the good news, at least you got it working and learn to figure out how to narrow down the problem to the bad board.
                      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


                        #12
                        Re: Samsung LN32C540 won't turn on

                        Lately, it's so slow the TV business and it seems that the competition is getting bigger. I have to pay more for a TV, just to be sure that I'll get them.
                        Need the money to change my car to a CUV, for TVs and my bad back.
                        I'm thinking 2014 Mazda CX-5. I have a 2008 VW Golf/Rabbit.

                        Comment


                          #13
                          Re: Samsung LN32C540 won't turn on

                          I no longer pick up new Samsung under 40" which have obvious main board faults (like standby LED but not turning on.) Too much chance it is the main 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


                            #14
                            Re: Samsung LN32C540 won't turn on

                            Usually I wouldn't pick up anything below 40", but when there is nothing out there, I don't have a choice.

                            Comment

                            Working...
                            X