Announcement

Collapse
No announcement yet.

Samsung PS50B455B1WXXE Plasma died

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

    Samsung PS50B455B1WXXE Plasma died

    Hi there

    I have a Samsung PS50B455B1WXXE Plasma bought in 2009, last few months it have had brightnes flickering when cold, mainly when showing dark sceens, like its been flipping between energysaving and standrad mode very fast, 10 minutes of watching and it have worked normaly.

    A few days ago it started as usualy, a few minutes after startup it just shut of completely, and restarted and shut, on/off/on/off, if I press buttons on remote the red led blinks as a sign of recieveing but it wont react and its stuck in its endless loop.

    as soon as I connect the power it goes exactly like this:

    click (relay) - tick tick tick tick tick (soft ticks) - click (relay) - short pause - click - tick....... and so on.

    I have inspected all boards for bad caps and see no usual signs off bad caps, psu board have no sign of bad soldering.

    the boards have the folowing modelnumbers:

    psu: P08540A BN44-00274B Rev 1.0
    Mainboard? (small one under psu): LJ41-05903A Rev R1.2
    board with tuner (lower right): BN41-01180A
    Y-M? (left big thingy): LJ41-05905A Rev 1.15
    X-M? (Right not so big thing on top of tunerboard) :LJ41-05904A Rev 1.13

    I hav tried to disconnect Y-M from psu, that will stop the restarting, Va and Vs gains correct values (55v/210V) and i can hear i soft buzzing from the X-M board. but connected they will never show any voltage.

    If i disconnect the x-m and leave y-m connected it will keep restarting.

    I have tried to disconnect the button panel.

    If i disconnect mainboard? (small one under psu) Psu boots up and i can measure a correct 5,3 volts, if i connect the 5,3v and ground from psu to main i can hear soft bussing from Y-M but no voltage from va/vs.

    Please help!

    Best regards / Markus

    #2
    Re: Samsung PS50B455B1WXXE Plasma died

    the soft ticking comes from the psu btw.

    Comment


      #3
      Re: Samsung PS50B455B1WXXE Plasma died

      Bad caps dare I say?

      Not enough power through transformer can cause the buzzing... Ticking is probably PSU shutting down and restarting but stuck in loop as its picking up a fault.

      Comment


        #4
        Re: Samsung PS50B455B1WXXE Plasma died

        Pics of boards and chassis?

        Comment


          #5
          Re: Samsung PS50B455B1WXXE Plasma died

          The clicking is the psu starting and shuting down, the ticking is from the psu between the start and stop.

          I measured the resistance between ground and VS on y-m and got 0 (2000 ohm scale) seems like my Ymain is shut but Im not a pro, any comments?
          Attached Files

          Comment


            #6
            Re: Samsung PS50B455B1WXXE Plasma died

            Pic of the psu is very out of focus, can you reshoot it

            Comment


              #7
              Re: Samsung PS50B455B1WXXE Plasma died

              Here we go
              Attached Files

              Comment


                #8
                Re: Samsung PS50B455B1WXXE Plasma died

                I have removed the y-m board and ohm measured around the vs path, its mainly 5 capacitors and when i measure over them i get 0 ohms, should i remove them and measure them individualy?
                Attached Files

                Comment


                  #9
                  Re: Samsung PS50B455B1WXXE Plasma died

                  Some of those caps on the psu don't look too flat from that pic, are any of them even slightly bulging?

                  ESR test them to be sure

                  Comment


                    #10
                    Re: Samsung PS50B455B1WXXE Plasma died

                    Nope, not even slightly bulged, they are straiter than a homofobic texas republican! :p

                    Does anyone know if vs on y-main is suposed to measure 0 ohm to ground?

                    Comment


                      #11
                      Re: Samsung PS50B455B1WXXE Plasma died

                      Originally posted by noki View Post
                      Does anyone know if vs on y-main is suposed to measure 0 ohm to ground?
                      Definitely bad... It should measure in the tens to hundreds of kilohms when good.
                      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


                        #12
                        Re: Samsung PS50B455B1WXXE Plasma died

                        Could it be the caps (no visual problems) on the ymain, marked on pic.

                        Have had problems with unstable brightnes for a few months...

                        Comment


                          #13
                          Re: Samsung PS50B455B1WXXE Plasma died

                          No, likely a shorted FET somewhere. Bad firmware on the control board puts more stress on sustain boards, which can lead to premature failure. After you replace or repair the Y-main you MUST apply the firmware update to prevent future failures.
                          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 PS50B455B1WXXE Plasma died

                            The firmware update is crap fram a user view, it forgets chanels and some functions are missbehaving, but ofcourse, its better with a missbehaving tv than a dead one...

                            Comment


                              #15
                              Re: Samsung PS50B455B1WXXE Plasma died

                              Well, that's Samsung for you...
                              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


                                #16
                                Re: Samsung PS50B455B1WXXE Plasma died

                                I have bought a 60" LG now, hope it will work better.

                                The samsung have gave us 4 years with a lot of hours so its not there worst model, but a few years back one expected 15 years from a tv...

                                Will try to fix the ymain, updates will folow.

                                Comment

                                Working...
                                X