ps50c77hdx/xec

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  • Jimmy1979
    Senior Member
    • Apr 2015
    • 120
    • holland

    #21
    Re: ps50c77hdx/xec

    Yes ps-on collapse to 0,2v

    Comment

    • Jimmy1979
      Senior Member
      • Apr 2015
      • 120
      • holland

      #22
      Re: ps50c77hdx/xec

      Yes ps-on collapse to 0,2v

      Comment

      • Jimmy1979
        Senior Member
        • Apr 2015
        • 120
        • holland

        #23
        Re: ps50c77hdx/xec

        Originally posted by ReeceyBurger123
        Ok when it shuts down does Pson collapse ?
        Maybe other idea?

        Comment

        • Alastair E
          Chief Womble
          • Mar 2013
          • 1963
          • U.K.

          #24
          Re: ps50c77hdx/xec

          You'll need to bulb the psu--see if it will run ok without the set...

          disconnect every plug except mains in from the psu, short ps/on to std 5v and vs on to gnd. Attach 100-150W std lightbulb--not energy-saver--to vs and gnd.

          Apply power to mains input. bulb should light and all other supplies should test as noted on the sockets.
          TELEFIX

          How PLASMA SCREENS WORK, X-SUS and Y-SUS what they do--
          http://www.irf.com/technical-info/appnotes/an-1088.pdf
          PLEASE DO NOT EMAIL ME PRIVATELY FOR REPAIR ADVICE. QUESTIONS BELONG ON THE FORUM!

          Comment

          • Jimmy1979
            Senior Member
            • Apr 2015
            • 120
            • holland

            #25
            Re: ps50c77hdx/xec

            Originally posted by Alastair E
            You'll need to bulb the psu--see if it will run ok without the set...

            disconnect every plug except mains in from the psu, short ps/on to std 5v and vs on to gnd. Attach 100-150W std lightbulb--not energy-saver--to vs and gnd.

            Apply power to mains input. bulb should light and all other supplies should test as noted on the sockets.
            Oke i will try this and see if it runs oke.
            Thanx

            Comment

            • flocko
              Badcaps Legend
              • Nov 2012
              • 1121
              • uk

              #26
              Re: ps50c77hdx/xec

              Check for 5v stby. then Ps/on should be grounded( made low). this will bring the relays in (all low voltages will now show ) . Vs/on needs a 470-1000 ohm resister jumper between it and 5v stby( made high) to bring the board to life (high voltages Va/Vs will now show if working) test and report

              Comment

              • Jimmy1979
                Senior Member
                • Apr 2015
                • 120
                • holland

                #27
                Re: ps50c77hdx/xec

                Originally posted by flocko
                Check for 5v stby. then Ps/on should be grounded( made low). this will bring the relays in (all low voltages will now show ) . Vs/on needs a 470-1000 ohm resister jumper between it and 5v stby( made high) to bring the board to life (high voltages Va/Vs will now show if working) test and report
                ThanxπŸ‘πŸ»

                I have grounded ps/on but the relay doesn't start click voltage 4,0v
                Standby 5v
                I have changed the relay to make sure that isn't the problem but still the same.
                Any idea why?

                Comment

                • flocko
                  Badcaps Legend
                  • Nov 2012
                  • 1121
                  • uk

                  #28
                  Re: ps50c77hdx/xec

                  So you have Stby 5v / just the relays not coming in? start checking ICQ805 check the in and out voltages when grounding Ps on .dont forget use hot ground - leg main cap when testing , CQ802/807and 815 can cause this loss as well

                  Comment

                  • Jimmy1979
                    Senior Member
                    • Apr 2015
                    • 120
                    • holland

                    #29
                    Re: ps50c77hdx/xec

                    Originally posted by flocko
                    So you have Stby 5v / just the relays not coming in? start checking ICQ805 check the in and out voltages when grounding Ps on .dont forget use hot ground - leg main cap when testing , CQ802/807and 815 can cause this loss as well
                    Oke i will check this thanx for your help mateπŸ‘πŸ»

                    Comment

                    • Jimmy1979
                      Senior Member
                      • Apr 2015
                      • 120
                      • holland

                      #30
                      Re: ps50c77hdx/xec

                      Originally posted by flocko
                      So you have Stby 5v / just the relays not coming in? start checking ICQ805 check the in and out voltages when grounding Ps on .dont forget use hot ground - leg main cap when testing , CQ802/807and 815 can cause this loss as well
                      I have checked icq805 and voltage in pulsate between 4v and 6v and out 4v.
                      Cq802/807 and 815 i changed them for new caps.

                      Comment

                      • flocko
                        Badcaps Legend
                        • Nov 2012
                        • 1121
                        • uk

                        #31
                        Re: ps50c77hdx/xec

                        Can you check the 5v Stby when you put Ps on to ground is it still holding 5v?

                        Comment

                        • Jimmy1979
                          Senior Member
                          • Apr 2015
                          • 120
                          • holland

                          #32
                          Re: ps50c77hdx/xec

                          Originally posted by flocko
                          Can you check the 5v Stby when you put Ps on to ground is it still holding 5v?
                          Yes 5v still there

                          Comment

                          • flocko
                            Badcaps Legend
                            • Nov 2012
                            • 1121
                            • uk

                            #33
                            Re: ps50c77hdx/xec

                            And ICQ 805 in and out voltage when Ps on is grounded on and off no change, you are using neg leg of main cap (hot ground) as ground for testing ICQ805?

                            Comment

                            • Jimmy1979
                              Senior Member
                              • Apr 2015
                              • 120
                              • holland

                              #34
                              Re: ps50c77hdx/xec

                              Originally posted by flocko
                              And ICQ 805 in and out voltage when Ps on is grounded on and off no change, you are using neg leg of main cap (hot ground) as ground for testing ICQ805?
                              Oke i will check this and let jou know.

                              Comment

                              • Jimmy1979
                                Senior Member
                                • Apr 2015
                                • 120
                                • holland

                                #35
                                Re: ps50c77hdx/xec

                                Originally posted by flocko
                                And ICQ 805 in and out voltage when Ps on is grounded on and off no change, you are using neg leg of main cap (hot ground) as ground for testing ICQ805?
                                When i'm using hot ground and test icq805 with ps-on grounded 0v in and out.
                                And when ps-on not grounded the same.

                                Comment

                                • flocko
                                  Badcaps Legend
                                  • Nov 2012
                                  • 1121
                                  • uk

                                  #36
                                  Re: ps50c77hdx/xec

                                  Do you have the schematic for BN44-00161. you can find it at Toms service manuals in the tv repair library. You need to back track from ICQ805 to try and find were your problem is. the viper is working as you would not have 5v stby. start by checking diode DB807 if this is open you would get Ov to ICQ805. if you get the schematic this will help to back track.update and if you get stuck we are here

                                  Comment

                                  • Jimmy1979
                                    Senior Member
                                    • Apr 2015
                                    • 120
                                    • holland

                                    #37
                                    Re: ps50c77hdx/xec

                                    Originally posted by flocko
                                    Do you have the schematic for BN44-00161. you can find it at Toms service manuals in the tv repair library. You need to back track from ICQ805 to try and find were your problem is. the viper is working as you would not have 5v stby. start by checking diode DB807 if this is open you would get Ov to ICQ805. if you get the schematic this will help to back track.update and if you get stuck we are here
                                    Oke thanxπŸ‘πŸ»

                                    Comment

                                    • lamouche1
                                      Member
                                      • Feb 2011
                                      • 12
                                      • Canada

                                      #38
                                      Re: ps50c77hdx/xec

                                      i have nearly the exact problem with a bn44-00162 i have no 15V at icq805 output and nothing at the input i'ved track the voltage down to the qc803 pnp transistor it got around 20v at the emitter coming from the tb801/ viper22 area
                                      the transistor test good the base of the transistor seems to come from pcq802 opto. i'm stuck there for the moment. should i check on the cold side of the opto or stay on hot side?

                                      for the ps_on i'm using a resistor under 1k
                                      i got my 5v standby and it's stable.
                                      i replace the cb816 22uf 450v
                                      checked cq802 cq807 and cq815. the all are ok
                                      all four fets are ok


                                      the guy who gave me the tv set is not sure if the tv quit during a thunder storm

                                      Comment

                                      • budm
                                        Badcaps Legend
                                        • Feb 2010
                                        • 40746
                                        • USA

                                        #39
                                        Re: ps50c77hdx/xec

                                        If I remember this BN44-00162A correctly, when PS-ON is LOW, it is = Power supply ON. it is opposite from most other power supplies.
                                        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

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                                        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

                                        • lamouche1
                                          Member
                                          • Feb 2011
                                          • 12
                                          • Canada

                                          #40
                                          Re: ps50c77hdx/xec

                                          ps_on is at ground via a 1k resistor

                                          Comment

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