Sanyo DP40142 No backlight

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  • keithdisco
    New Member
    • Apr 2012
    • 2
    • uk

    #41
    Re: Sanyo DP40142 No backlight

    i know its an old post but i totally agree very bad design i would never buy one of these pos tvs

    i found exact same issue as above blown resistor
    with burnt connections between led strips
    new name is toss-shita

    Comment

    • RAMSELECTRONICS
      ATARI boy
      • Jul 2015
      • 48
      • USA

      #42
      Re: Sanyo DP40142 No backlight

      Hello all, I think it is new post for now, I am talking about the power supply from DP40142. I checked the voltage the 5V is working fine, I see the 12V and 24V are group and does not give output. I replaced the chip SSC9512S and no luck.

      I tested with 2 of MOSFET are fine.

      Any one know about this? please help. THANK YOU!

      Comment

      • RAMSELECTRONICS
        ATARI boy
        • Jul 2015
        • 48
        • USA

        #43
        Re: Sanyo DP40142 No backlight

        Originally posted by RAMSELECTRONICS
        Hello all, I think it is new post for now, I am talking about the power supply from DP40142. I checked the voltage the 5V is working fine, I see the 12V and 24V are group and does not give output. I replaced the chip SSC9512S and no luck.

        I tested with 2 of MOSFET are fine.

        Any one know about this? please help. THANK YOU!
        I forgot to add this, the power supply is FSP140-4F01

        Comment

        • Shane711
          Badcaps Veteran
          • Dec 2014
          • 493
          • USA

          #44
          Re: Sanyo DP40142 No backlight

          I am surprised to see Herbssat's picture of the LED driver board inside the panel. I have never seen a circuit board inside the panel like that before. I have this TV, it seems to be turning on but no back light. I will have to disassemble the screen to see if I have this same problem.

          Comment

          • budm
            Badcaps Legend
            • Feb 2010
            • 40746
            • USA

            #45
            Re: Sanyo DP40142 No backlight

            https://www.badcaps.net/forum/showpo...4&postcount=18
            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

            • Shane711
              Badcaps Veteran
              • Dec 2014
              • 493
              • USA

              #46
              Re: Sanyo DP40142 No backlight

              Thanks budm, that is a very good picture. I found the LED driver board. This is the first time I have seen it in this location.

              Seems my LED driver board is good because I only have 2 LED strips working. Got to leave for a while and when I get back I will remove the bad LEDs and replace them with good ones.

              Comment

              • Shane711
                Badcaps Veteran
                • Dec 2014
                • 493
                • USA

                #47
                Re: Sanyo DP40142 No backlight

                This Sanyo DP40142 is a piece of junk, man they don't make them like they used to. It looks like I am going to have to replace 80% of all the LEDs, I would say then that they are all bad. Looks like I have no choice but before I do all this work I am going to turn the TV on again with a light behind the screen just to make sure the LCD screen is good. No point doing all this work for nothing.

                Comment

                • Shane711
                  Badcaps Veteran
                  • Dec 2014
                  • 493
                  • USA

                  #48
                  Re: Sanyo DP40142 No backlight

                  Well, good news. The TV is fixed. I had to replace 2 LEDs but I thought I was going to have to replace all of them because 2 strips were bright and the other 3 were very dim. But I put it back together without the screen and the LEDs were very bright. So then I put the TV all back together and it seems to be working good. Time will tell. I have included a picture.

                  Once again this web site has helped me fix a TV because I thought for sure it was the main board. I best keep reminding myself these LEDs love to burn out.
                  Attached Files

                  Comment

                  • budm
                    Badcaps Legend
                    • Feb 2010
                    • 40746
                    • USA

                    #49
                    Re: Sanyo DP40142 No backlight

                    Thanks for the follow-up on the repair.
                    What LEDs did you use for the repair?
                    So far to me the TVs with LED backlights seem to have 90% failure due to failed LEDs.
                    Last edited by budm; 05-05-2016, 10:35 AM.
                    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

                    • Shane711
                      Badcaps Veteran
                      • Dec 2014
                      • 493
                      • USA

                      #50
                      Re: Sanyo DP40142 No backlight

                      I have a bunch laying around that I removed from TVs with bad panels. So I had some that looked almost exactly the same. I used my small heat gun work station to remove them. I then touched up the solder on the TV strip and replaced 2 LEDs on the strip next to the LED driver board.

                      It pays to keep parts laying around. I do my best to keep the parts organized but it's not easy.
                      Attached Files

                      Comment

                      • Hartman
                        New Member
                        • Oct 2014
                        • 1
                        • The Netherlands

                        #51
                        Re: Sanyo DP40142 No backlight

                        R053 is not 85 ohms but the smd code is 05B which is 1k1 ohm (1100 ohms)
                        I just repaired my Philips 40pfl3208 which uses the same panel.
                        In my case no backlight and R053 was 7kohm instead of 1k1
                        I also saw that the connecors between the ledstrips made very poor contact.
                        You will have to bypass all of these in order to repair it, so that it is reliable.
                        The led driver passes its power onto a green strip, that transfer it to the horizontal positioned led strips.
                        I also bypassed these connectors in order to make it reliable.
                        Greetings
                        Jeroen Hartman
                        Cctv technician
                        Netherlands

                        Comment

                        • Shane711
                          Badcaps Veteran
                          • Dec 2014
                          • 493
                          • USA

                          #52
                          Re: Sanyo DP40142 No backlight

                          Same exact TV as in post #47 & #48. The TV again burnt out some LEDs but this time I noticed burnt contacts on the strips and maybe this short was causing the LEDs to burn out. Seems to only happen on this one strip. So I soldered on some jumper wires to bypass the connectors and the TV lives once again. So far no problems with the LED driver board.

                          Comment

                          • EGM
                            New Member
                            • Sep 2017
                            • 6
                            • USA

                            #53
                            Re: Sanyo DP40142 No backlight

                            Newbie here. I've got a similar problem on a Sanyo DP40142 TV. Backlight driver board SSL400_0D5A REV:1.0 I'm not having any luck on tracking schematics for this TV or board. It has a burnt resistor on R005 and as normal, I cant read the value. Can anyone lend me a hand trying to figure this one out or is there a way I can figure out the resistance? I've tested the leds and the only thing looking bad at this time is that resistor. Something burned it up and I'd like to track it down but need some help.

                            Comment

                            • EGM
                              New Member
                              • Sep 2017
                              • 6
                              • USA

                              #54
                              Re: Sanyo DP40142 No backlight

                              Shane771 You wouldn't happen to have this BLD board laying around?
                              Sanyo DP40142 TV. Backlight driver board SSL400_0D5A REV:1.0
                              If you do, can you tell me the resistor number on R005?
                              Thanks for your time.

                              Comment

                              • Shane711
                                Badcaps Veteran
                                • Dec 2014
                                • 493
                                • USA

                                #55
                                Re: Sanyo DP40142 No backlight

                                Yes, I have the board and I will get it open sometime soon because I have to repair the LEDs AGAIN! I will get the number for you. The same TV has burnt out LEDs for the third time. The same TV that I fixed in post #47, #48, & #52.

                                Does anyone have any ideas on how I can prevent the LEDs from burning out?

                                Comment

                                • budm
                                  Badcaps Legend
                                  • Feb 2010
                                  • 40746
                                  • USA

                                  #56
                                  Re: Sanyo DP40142 No backlight

                                  Did you turn down the Backlights level for all input modes?
                                  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

                                  • Shane711
                                    Badcaps Veteran
                                    • Dec 2014
                                    • 493
                                    • USA

                                    #57
                                    Re: Sanyo DP40142 No backlight

                                    Yep, I did. Could it be power surges?

                                    Comment

                                    • budm
                                      Badcaps Legend
                                      • Feb 2010
                                      • 40746
                                      • USA

                                      #58
                                      Re: Sanyo DP40142 No backlight

                                      May be checking the LED flowing through the LED string to see what you get. The replacement LED rated at about 400 mA or so?
                                      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

                                      • Shane711
                                        Badcaps Veteran
                                        • Dec 2014
                                        • 493
                                        • USA

                                        #59
                                        Re: Sanyo DP40142 No backlight

                                        budm, I really need to understand this, I just got another TV that was out by the trash, Very nice clean and brand new looking Samsung 46" and so I will start a new thread on that. 50% of the LEDs are burnt out.
                                        If I fix it with the same LEDs then it will only go bad again.

                                        So if I use LEDs with a higher amperage will that mean they will require more power? If they will have the same brightness but could handle higher work loads that would be the thing to do.

                                        And then I will have to figure out where to buy them.

                                        Comment

                                        • budm
                                          Badcaps Legend
                                          • Feb 2010
                                          • 40746
                                          • USA

                                          #60
                                          Re: Sanyo DP40142 No backlight

                                          Do you have the specification of the replacement you are using?
                                          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

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