Need Help Troubleshooting a Sanyo DP50740

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • gogettemguy
    New Member
    • Jun 2011
    • 9

    #1

    Need Help Troubleshooting a Sanyo DP50740

    So i picked up the Television from a friend of mine who had the TV since day 1, no problems with it at all... then one day, poof... and it sat in a closet for a few months till i got my hands on it.

    All signs were pointing towards a dead PSU, plug it in, and turn it on, relays fire, and a few seconds later, the On LED goes out, you can press the Power button a total of 3 times, afterwards the LED will not respond.

    I had replaced the PSU on a whim of that being an issue even ordered it before i dragged the TV out of the closet. (new PSU was from a damaged display, stated that it did light up) but i guess i have bigger issues on my hands)
    All capacitors seem to be in good shape,
    so far i've disconnected each lead going around the circuit boards individually in hopes for a change, yet nothing... i get 15v coming out of the PSU but immediately drops to 0v.

    Attached are photos of the Television, im wondering what my next step should be...
    Attached Files
  • PlainBill
    Badcaps Legend
    • Feb 2009
    • 7034
    • USA

    #2
    Re: Need Help Troubleshooting a Sanyo DP50740

    Originally posted by gogettemguy
    So i picked up the Television from a friend of mine who had the TV since day 1, no problems with it at all... then one day, poof... and it sat in a closet for a few months till i got my hands on it.

    All signs were pointing towards a dead PSU, plug it in, and turn it on, relays fire, and a few seconds later, the On LED goes out, you can press the Power button a total of 3 times, afterwards the LED will not respond.

    I had replaced the PSU on a whim of that being an issue even ordered it before i dragged the TV out of the closet. (new PSU was from a damaged display, stated that it did light up) but i guess i have bigger issues on my hands)
    All capacitors seem to be in good shape,
    so far i've disconnected each lead going around the circuit boards individually in hopes for a change, yet nothing... i get 15v coming out of the PSU but immediately drops to 0v.

    Attached are photos of the Television, im wondering what my next step should be...
    A close up of the power supply might be helpful. Also, pictures of the two labels on the back of the plasma panel might help.

    PlainBill
    For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

    Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

    Comment

    • Sleblanc
      New Member
      • Sep 2011
      • 2

      #3
      Re: Need Help Troubleshooting a Sanyo DP50740

      Hi there,

      I too have the same problem as described in the original post. We've changed the PSU, but we get the same problem.

      Since the original poster did not reply with the pictures asked for, I will provide those I have taken from the PSU itself and the two stickers at the back of the panel.

      I will provide a link to the images, because they are too large to include directly in this post.

      http://www.atelierinfo.net/SANYO1.JPG
      http://www.atelierinfo.net/SANYO2.JPG
      http://www.atelierinfo.net/SANYO3.JPG

      Any help would be greatly appreciated. Thanks.

      Comment

      • PlainBill
        Badcaps Legend
        • Feb 2009
        • 7034
        • USA

        #4
        Re: Need Help Troubleshooting a Sanyo DP50740

        Originally posted by Sleblanc
        Hi there,

        I too have the same problem as described in the original post. We've changed the PSU, but we get the same problem.

        Since the original poster did not reply with the pictures asked for, I will provide those I have taken from the PSU itself and the two stickers at the back of the panel.

        I will provide a link to the images, because they are too large to include directly in this post.

        http://www.atelierinfo.net/SANYO1.JPG
        http://www.atelierinfo.net/SANYO2.JPG
        http://www.atelierinfo.net/SANYO3.JPG

        Any help would be greatly appreciated. Thanks.
        Due to what might be an excess of caution, I won't access pictures hosted offsite. My favorite picture viewer and resizer is Vueprint. It's small, fast, and best of all, free; note the serial number posted on the page. Also, you MIGHT be able to attach them directly by using the URLs you used above.

        PlainBill
        For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

        Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

        Comment

        • KTMLew
          Member
          • Sep 2011
          • 37

          #5
          Re: Need Help Troubleshooting a Sanyo DP50740

          Let me try this again...his links were safe.
          Attached Files

          Comment

          • PlainBill
            Badcaps Legend
            • Feb 2009
            • 7034
            • USA

            #6
            Re: Need Help Troubleshooting a Sanyo DP50740

            Standard first step: With all cables hooked up, check the output voltages of the power supply to see if any fail to come up. Start with the cables running from the power supply to the sustain boards. If a power rail going to a sustain fails to come up, try disconnecting the cable and rechecking. Next step - check any fuses on the sustain boards.

            PlainBill
            Last edited by PlainBill; 09-20-2011, 05:14 PM.
            For a number of reasons, both health and personal, I will no longer be active on this board. Any PMs asking for assistance will be ignored.

            Never be afraid to try something new. Remember, amateurs built the ark. Professionals built the Titanic.

            Comment

            • Sleblanc
              New Member
              • Sep 2011
              • 2

              #7
              Re: Need Help Troubleshooting a Sanyo DP50740

              Thanks for the answers.

              There's been a couple of developments in this. I've unplugged everything except the following boards on the original poster's first picture: central board, plus the two underneath.

              I unhooked the right one with all the connections to the plasma screen. Same with the three left ones, and the two bottom ones. The result: the TV no longer shuts down.

              I then hooked in the right board, and tested, it still worked. I tested this hooking one cable at a time. Eventually, I was able to come up with only 4 cables still unhooked: top one on the left board (the cable that goes all the way to the right board), the central cable on the left board (the one connected to the central power board), the ribbon at the bottom of the left board that goes to the smaller central panel, plus the small ribbon that connects the two bottom boards.

              I figured that the TNPA5063 board must be the problem. I don't understand why the ribbon connecting the two bottom boards also causes the issue, and am not sure if I should order a replacement TNPA5063 board because of that extra cable that causes the screen to shut down.

              Also, the two left pannels which are connected to the plasma panel are currently hooked into the TNPA5063 board, without problem.

              Anyone has any ideas?

              EDIT: After verification, the two bottom boards are the buffer boards (TNPA5079 and TNPA5080). I still don't understand why the screen would shut down when these two are connected together however.
              Last edited by Sleblanc; 09-27-2011, 11:36 AM.

              Comment

              • cptsheffield
                New Member
                • Jul 2012
                • 1
                • usa

                #8
                Re: Need Help Troubleshooting a Sanyo DP50740

                i have the same issue. Just wondering if you ever found out what was the problem

                Comment

                • googunhammer
                  New Member
                  • Nov 2012
                  • 1
                  • usa

                  #9
                  Re: Need Help Troubleshooting a Sanyo DP50740

                  Has anyone fixed the issues with the DP50740 restarting problem?

                  Comment

                  • drpj23
                    Badcaps Veteran
                    • May 2012
                    • 528
                    • USA

                    #10
                    Re: Need Help Troubleshooting a Sanyo DP50740

                    I have had this Sanyo have similar problems. Mine, more particularly, was the TV cutting on and the screen staying primed for about 30 seconds and then it would restart. I found disconnecting the main from the controller board (via LVDS) stopped the resetting. Eventually, I found the main was the issue (also the only part that wasn't Panasonic's) but unfortunately, I did not isolate the problem on the main board due to being under a time constraint. Hope that helps somewhat.

                    Comment

                    • llcoolt99
                      New Member
                      • Mar 2013
                      • 1
                      • United States

                      #11
                      Re: Need Help Troubleshooting a Sanyo DP50740

                      Drpj23 is your tv fixed and still running after replacing the main board. Mine is doing the exact same thing as yours (rebooting every 30 seconds and won't reboot when I disconnect the LVDS). Just wanting to know if it was worth spending the $100 for the main board part. Thanks

                      Comment

                      • splitcrete
                        Badcaps Veteran
                        • Dec 2012
                        • 387
                        • usa

                        #12
                        Re: Need Help Troubleshooting a Sanyo DP50740

                        Replace the three parts in red boxes,and your main board should be good to go.
                        Attached Files

                        Comment

                        • ricosavy
                          Badcaps Veteran
                          • Jul 2012
                          • 457
                          • united states

                          #13
                          Re: Need Help Troubleshooting a Sanyo DP50740

                          I replaced all those parts but no success those regulators were not my problem.One problem I have is no voltage on 13v test point but there is no cirtcuit there.is there suppose to be voltage there.

                          Comment

                          • Hornet10_10
                            New Member
                            • May 2014
                            • 3
                            • Uss

                            #14
                            Re: Need Help Troubleshooting a Sanyo DP50740

                            I have the same issue no voltage on the audio circuit, what was the outcome?

                            Comment

                            Related Topics

                            Collapse

                            • blues_spirit
                              practical courses for troubleshooting pc motherboards
                              by blues_spirit
                              Hello from France,
                              mon2 kindly advised me to post a thread to ask the question(s) I'm concerned about. I'm new to the forum and I'm looking for practical courses for troubleshooting pc motherboards especially laptops in Europe, if possible in France. I have been a computer network system administrator and a corrector of administration modules for automated programs under Unix. But I really miss the practical "ops" side of troubleshooting. So I would like to start from the beginning: 1.8V, 3.3V, 5V and 19V tests for example, etc...
                              Do you think this is feasible for me? I...
                              12-18-2022, 12:56 PM
                            • gcrezz
                              GV-N2060OC-6GD REV 2.0 GIGABYTE video card troubleshooting assistance needed.
                              by gcrezz
                              The issue with this video card is the HDMI port. Specifically on pin 19 (Diode checks on all other pins are normal). When i do a diode check on it from the pin on the board itself, I have nothing. There is also no short on the pin. Resistance reads about 200k. Normally on any HDMI pin 19 I would expect some voltage drop anywhere from .5v to 1.2v but here, I have nothing. The card is operational and can be used via the displayPort ports, but not through the HDMI. Attached you will find the pdf schematics for the card on page 22. I have verified that all of the resistors on this line before the...
                              07-25-2024, 09:49 AM
                            • CrewmanRedShirt
                              Looking for assistance troubleshooting a Panasonic TC-P65ZT60 with 3 LED Fast Blinks
                              by CrewmanRedShirt
                              Hello all,
                              As the title states, I followed the troubleshooting guide located here: https://www.manualslib.com/manual/23...page=53#manual, which concluded the 'A' board needs to be replaced. Looking around the net and eBay, I see that there are repair services for the board (TNPH1043UE? Not sure if it is a 'UE' as the suffix grid does not appear marked). What additional troubleshooting can be performed to ensure 1) this board is the problem and 2) since there are repair services, what are they fixing on the board?) I expected 3.3V not to be available anywhere...
                              07-13-2024, 11:02 AM
                            • cj_reha
                              Mystery 80s Sanyo cap - perhaps polymer?
                              by cj_reha
                              Hey all I've been working on a 1984 Sanyo 27" color TV which had a smattering of bad caps in the video switching circuit. I found this oddball little 1uF 25V cap which looks to me like an early polymer, but I can't find concrete info proving it. I know Sanyo was a big player in early polymer cap development and this is the time period where they were just getting on the market, so I'm wondering if anyone has crusty old datasheets that could help identify it and determine if my suspicions are right? It has the same epoxy end seal and font/formatting as some old stock Os-Cons I've got laying...
                              01-06-2023, 09:24 AM
                            • Zippie
                              Troubleshooting Old Chiefmax 650Watt ATX Switching Power Supply
                              by Zippie
                              I’m looking for some advice troubleshooting an old Chiefmax 650w power supply in a PC, if it’s advisable to dig into it.

                              Worst case I can replace the PSU, I’m just interested in learning the troubleshooting process. However, it’s out of my area of expertise and I could use some direction.

                              During PC operation I heard a loud pop noise, like a cap gun and the tower lost power.

                              Initially there is no power output 3.3v, 5v, or 12v when jumping the power on pin to ground. Also, no fan power.

                              Opening the PSU the only things visible initially...
                              03-07-2024, 07:58 PM
                            • Loading...
                            • No more items.
                            Working...