Acoustic solutions LCD26761HDF no backlight

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  • sienoki
    sienoki
    • Jan 2012
    • 314

    #21
    Re: Acoustic solutions LCD26761HDF no backlight

    Originally posted by sienoki
    Sorry for measuring white pin out not properly 1-27
    1--0v 2--0v
    3--0v 4--07.9
    5--0v 6--0v
    7--0v 8--0v
    9--0v 10--0v
    11--11.8v 12--11.8v
    13--0v 14--05.0v
    15--03.2v 16--03.2v
    17--05.0v 18--03.3v
    19--05.0v 20--03.2v
    21--0v 22--03.2v
    23--0v 24--0v
    25--24.3v 26--24.2v
    27--24.3v
    I missed 28 pin just realised doh..can retest if needed..too many paint fumes from decorating..what would be my next step..thx

    Comment

    • sienoki
      sienoki
      • Jan 2012
      • 314

      #22
      Re: Acoustic solutions LCD26761HDF no backlight

      Originally posted by sienoki
      I missed 28 pin just realised doh..can retest if needed..too many paint fumes from decorating..what would be my next step..thx
      Im still stumped for getting my hands on a decent camera for now..i came across another forum while googling this model faults & 1 suggestion was to replace C802 & C934 the 2 block reddish caps which markings are 105K 450MFF & IC802 which is underneath them 2 caps ic marking E131 FAN7529..can any1 shed any light on this..thx
      On the schematics ive attached that IC802 is a IRF7314 but i dont know owt about schematics..thx
      Last edited by sienoki; 03-02-2012, 05:55 PM.

      Comment

      • sienoki
        sienoki
        • Jan 2012
        • 314

        #23
        Re: Acoustic solutions LCD26761HDF no backlight

        Originally posted by sienoki
        Im still stumped for getting my hands on a decent camera for now..i came across another forum while googling this model faults & 1 suggestion was to replace C802 & C934 the 2 block reddish caps which markings are 105K 450MFF & IC802 which is underneath them 2 caps ic marking E131 FAN7529..can any1 shed any light on this..thx
        On the schematics ive attached that IC802 is a IRF7314 but i dont know owt about schematics..thx
        Are these pics better for tracing 24v line..thx
        My pics wont upload can i show them with another method..thx
        Last edited by sienoki; 03-03-2012, 02:44 PM.

        Comment

        • sienoki
          sienoki
          • Jan 2012
          • 314

          #24
          Re: Acoustic solutions LCD26761HDF no backlight

          Originally posted by sienoki
          Are these pics better for tracing 24v line..thx
          My pics wont upload can i show them with another method..thx
          http://i1068.photobucket.com/albums/...5/P1000810.jpg
          http://i1068.photobucket.com/albums/...P1000796-1.jpg
          hope its ok for now using this method..thx

          Comment

          • sienoki
            sienoki
            • Jan 2012
            • 314

            #25
            Re: Acoustic solutions LCD26761HDF no backlight

            Originally posted by sienoki
            http://i1068.photobucket.com/albums/...5/P1000811.jpg
            http://i1068.photobucket.com/albums/...5/P1000812.jpg
            http://i1068.photobucket.com/albums/...5/P1000813.jpg
            http://i1068.photobucket.com/albums/...5/P1000814.jpg
            http://i1068.photobucket.com/albums/...5/P1000816.jpg
            http://i1068.photobucket.com/albums/...5/P1000817.jpg
            http://i1068.photobucket.com/albums/...5/P1000820.jpg
            http://i1068.photobucket.com/albums/...5/P1000818.jpg
            http://i1068.photobucket.com/albums/...5/P1000819.jpg
            Any help plz to where i can start testing..thx

            Comment

            • tom66
              EVs Rule
              • Apr 2011
              • 32560
              • UK

              #26
              Re: Acoustic solutions LCD26761HDF no backlight

              What is the voltage across the big main cap in operation and when in standby?
              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

              • sienoki
                sienoki
                • Jan 2012
                • 314

                #27
                Re: Acoustic solutions LCD26761HDF no backlight

                Originally posted by tom66
                What is the voltage across the big main cap in operation and when in standby?
                Your wanting me to get blown up lol..how am i testing this safely..thx
                Am i black probe to ground screw and red to + leg of big cap..thx
                http://i1068.photobucket.com/albums/...5/P1000822.jpg
                heres my borrowed multimeter..thx
                Last edited by sienoki; 03-03-2012, 05:14 PM.

                Comment

                • tom66
                  EVs Rule
                  • Apr 2011
                  • 32560
                  • UK

                  #28
                  Re: Acoustic solutions LCD26761HDF no backlight

                  Originally posted by sienoki
                  Your wanting me to get blown up lol..how am i testing this safely..thx
                  Am i black probe to ground screw and red to + leg of big cap..thx
                  http://i1068.photobucket.com/albums/...5/P1000822.jpg
                  heres my borrowed multimeter..thx
                  Set meter to 1000V or closest range >=500V.

                  Red lead on one terminal black on the other.

                  Nothing touching ground and don't touch the cap yourself or you'll find out that it hurts a lot.
                  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

                  • selldoor
                    Slow Learner
                    • Dec 2010
                    • 7870

                    #29
                    Re: Acoustic solutions LCD26761HDF no backlight

                    Rubber gloves and wellies!!

                    Set your meter on 600volts DC - Red positive lead on positive leg of capacitor and black negative lead on negative leg of capacitor. Put the meter where you can easily see it without moving.

                    Just looked at your meter DC is the Flat bar with 3 dots under it and the V. Take care as I notice the
                    probes are broken and possibly cracked? For this voltage Id tape them up a bit.
                    Last edited by selldoor; 03-03-2012, 05:38 PM. Reason: meter
                    Please upload pictures using attachment function when ask for help on the repair
                    http://www.badcaps.net/forum/showthread.php?t=39740

                    Comment

                    • sienoki
                      sienoki
                      • Jan 2012
                      • 314

                      #30
                      Re: Acoustic solutions LCD26761HDF no backlight

                      Originally posted by selldoor
                      Rubber gloves and wellies!!

                      Set your meter on 600volts DC - Red positive lead on positive leg of capacitor and black negative lead on negative leg of capacitor. Put the meter where you can easily see it without moving.
                      That was scary but no permed hair lol
                      standby .946VDC
                      tv on 2.874VDC
                      .045 VAC &1.380 VAC from OL the readings werent steady they were up & down
                      Forgot i had this buried in cupboard..it read 400V in standny & tv on..thx
                      http://i1068.photobucket.com/albums/...5/P1000823.jpg
                      Should i recap all the psu caps with panasonics as they are all different named brands..or just hang on for now..thx
                      Last edited by sienoki; 03-03-2012, 06:22 PM.

                      Comment

                      • sienoki
                        sienoki
                        • Jan 2012
                        • 314

                        #31
                        Re: Acoustic solutions LCD26761HDF no backlight

                        Originally posted by sienoki
                        That was scary but no permed hair lol
                        standby .946VDC
                        tv on 2.874VDC
                        .045 VAC &1.380 VAC from OL the readings werent steady they were up & down
                        Forgot i had this buried in cupboard..it read 400V in standny & tv on..thx
                        http://i1068.photobucket.com/albums/...5/P1000823.jpg
                        Should i recap all the psu caps with panasonics as they are all different named brands..or just hang on for now..thx
                        Ive just hooked up dvd player as ived not heard sound as yet & sound is fine..so its just 24v not getting to the inverter..the fuse on inverter is fine..something is shorted or failing but no idea what that could be

                        Comment

                        • budm
                          Badcaps Legend
                          • Feb 2010
                          • 40746
                          • USA

                          #32
                          Re: Acoustic solutions LCD26761HDF no backlight

                          I am confused, what DC voltage do you get on that large cap when TV is plugged in but not turn on, what is it when the TV is 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

                          • sienoki
                            sienoki
                            • Jan 2012
                            • 314

                            #33
                            Re: Acoustic solutions LCD26761HDF no backlight

                            Originally posted by budm
                            I am confused, what DC voltage do you get on that large cap when TV is plugged in but not turn on, what is it when the TV is turn on?
                            Hi budm..im getting 342DC when just plugged in & same reading when power button pressed & blue led light on..thats with borrowed multimeter & 400V with my AC/DC voltmeter..thx
                            Getting 391DC when program button pressed as it must be on then & blue led is standby by..thx
                            So the cap is 450v is close to 400v enough?
                            Last edited by sienoki; 03-04-2012, 02:26 AM.

                            Comment

                            • tom66
                              EVs Rule
                              • Apr 2011
                              • 32560
                              • UK

                              #34
                              Re: Acoustic solutions LCD26761HDF no backlight

                              391V is okay, PFC is working.

                              Got a pic of the controller for the 24V (on the bottom of the board usually?)
                              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

                              • sienoki
                                sienoki
                                • Jan 2012
                                • 314

                                #35
                                Re: Acoustic solutions LCD26761HDF no backlight

                                Originally posted by tom66
                                391V is okay, PFC is working.

                                Got a pic of the controller for the 24V (on the bottom of the board usually?)
                                Hi tom..is the controller on any of the pics ive already posted..thx
                                When i mentioned about ariel in & having no signal display on screen..on the back cover of the tv next to the antenna it says 5vdc..am i right assuming that the antenna needs 5v if so thats not working aswell cos my ariel on my house roof is in perfect order with 100% signal on my nearly fixed lg 42"

                                Comment

                                • tom66
                                  EVs Rule
                                  • Apr 2011
                                  • 32560
                                  • UK

                                  #36
                                  Re: Acoustic solutions LCD26761HDF no backlight

                                  5VDC is probably for powered antennas... don't worry about it should be fine.

                                  Near the power MOSFET for the 24V there should be an IC what is the name/number on it and a photo would be helpful can't make out much from your pics.
                                  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

                                  • sienoki
                                    sienoki
                                    • Jan 2012
                                    • 314

                                    #37
                                    Re: Acoustic solutions LCD26761HDF no backlight

                                    Originally posted by sienoki
                                    Hi tom..is the controller on any of the pics ive already posted..thx
                                    When i mentioned about ariel in & having no signal display on screen..on the back cover of the tv next to the antenna it says 5vdc..am i right assuming that the antenna needs 5v if so thats not working aswell cos my ariel on my house roof is in perfect order with 100% signal on my nearly fixed lg 42"
                                    I dont know what controller im looking for..the pics i uploaded from photobucket are they clear enough to trace the 24v line?

                                    Comment

                                    • tom66
                                      EVs Rule
                                      • Apr 2011
                                      • 32560
                                      • UK

                                      #38
                                      Re: Acoustic solutions LCD26761HDF no backlight

                                      Originally posted by sienoki
                                      I dont know what controller im looking for..the pics i uploaded from photobucket are they clear enough to trace the 24v line?
                                      Not really.

                                      It will be a chip of some sort on the primary side.
                                      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

                                      • budm
                                        Badcaps Legend
                                        • Feb 2010
                                        • 40746
                                        • USA

                                        #39
                                        Re: Acoustic solutions LCD26761HDF no backlight

                                        Please look at the PDF, I need that P/N of the IC830 FOR THE 24VDC SMPS SECTION.
                                        At this point the PS_ON is OK, the power supply with PFC controlled will use the same signal to turn on the PFC circuits and the 24VDC power supply section at the same time.
                                        Attached Files
                                        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

                                        • sienoki
                                          sienoki
                                          • Jan 2012
                                          • 314

                                          #40
                                          Re: Acoustic solutions LCD26761HDF no backlight

                                          Originally posted by budm
                                          Please look at the PDF, I need that P/N of the IC830 FOR THE 24VDC SMPS SECTION.
                                          At this point the PS_ON is OK, the power supply with PFC controlled will use the same signal to turn on the PFC circuits and the 24VDC power supply section at the same time.
                                          Thx budm its been a very loooong day..the IC830 is FAN7711 VJ28..thx

                                          Comment

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