Sanyo DP50749 not switching on

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Chuper
    Member
    • Sep 2017
    • 36
    • Canada

    #1

    Sanyo DP50749 not switching on

    With everything connected when you press power button relay clicks, the green light comes for about 3-4 seconds, relay clicks light goes away, in one second tries again, clicks, green light comes for 3-4 seconds, clicks, light goes away.
    At this moment on the PSU BN44-00274A:

    Connector CN802 has:
    Pin1 - 5.3V - 0V
    Pin2 - 5.3V - 0V
    Pin3 - GND
    Pin4 - GND
    Pin5 - PS_ON - 3.058V
    Pin6 - VS_ON - 0V

    Connector CN801 has:
    Pin1 - PS_ON - 3.058V
    Pin2 - VS_ON - 0V (no connected wire)
    Pin3 - STBY - 5.285V
    Pin4 - GND_STBY
    Pin5 - GND_15Vmp (no connected wire)
    Pin6 - GND_15Vmp
    Pin7 - 15Vmp - 0V
    Pin8 - 15Vmp - 0V
    Pin9 - GND_5.3V (no connected wire)
    Pin10 - GND_5.3V
    Pin11 - GND_5.3V
    Pin12 - GND_5.3V
    Pin13 - 5.3V - 0V
    Pin14 - 5.3V - 0V
    Pin15 - 5.3V - 0V
    Pin16 - 5.3V - 0V
    Pin17 - GND_15V (no connected wire)
    Pin18 - GND_15V (no connected wire)
    Pin19 - 15V - 0V (no connected wire)
    Pin20 - GND_15V
    Pin21 - 15V - 0V (no connected wire)
    Pin22 - 15V - 0V
    Pin23 - N.C (AC_DET) - 5.266V
    Pin24 - N.C (Vt) - (no connected wire)

    Visual check gives no burned elements. All fuses are good.
    I found a service manual and the procedure of eliminating Main Signal Board. I did that with no luck meaning TV is not generating internal patterns without the Main Signal Board attached. So here during this test relay clicks ones (stays on) and in my understanding the PSU must be on. On three big capacitors CP801, CP802, CP803 I only got 158.2V across them. On the DX807 - 5.285V; on DX806 - 27V(must be 15V I guess), DS801 - 0.2V (must be Va with is 55V), DS825 - 0V (must be Vs wich is 210V).
    So the question is should I order a power supply? Or someone on here will help me track the problem down?
    Attached Files
  • budm
    Badcaps Legend
    • Feb 2010
    • 40746
    • USA

    #2
    Re: Sanyo DP50749 not switching on

    Does PS-ON Voltage change state when power switch is toggled on and off?
    Power supply board is SAMSUNG BN44-00274A.
    Most SAMSUNG Plasma power supply uses active low for PS-ON, MEANING <1V = ON, >2V = OFF.
    Please upload the service manual.
    Last edited by budm; 12-24-2017, 03:26 PM.
    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

    • Chuper
      Member
      • Sep 2017
      • 36
      • Canada

      #3
      Re: Sanyo DP50749 not switching on

      PS_ON does change it's value to low 0.022Vdc for those 3-4 seconds.
      Attached Files

      Comment

      • dskall
        Badcaps Legend
        • Oct 2016
        • 2905
        • usa

        #4
        Re: Sanyo DP50749 not switching on

        If you cannot generate test pattern. Most likely power supply. Repair kits available
        I assume no responsibility for any stupid suggestions I might post.

        Comment

        • dskall
          Badcaps Legend
          • Oct 2016
          • 2905
          • usa

          #5
          Re: Sanyo DP50749 not switching on

          I have this same TV. I have found the 3.3v regulator is about 2.7v. Ic 1630 P.47 in above SM. I removed it and applied 3.3v externally and tv works. My question. It is a sharp 5 terminal regulator and is a little difficult to find. Can I use a common 3.3v reg. to replace. Or other substitute. I believe one terminal is an enable pin. Not that good with circuits yet.
          Last edited by dskall; 02-09-2018, 05:28 PM.
          I assume no responsibility for any stupid suggestions I might post.

          Comment

          • budm
            Badcaps Legend
            • Feb 2010
            • 40746
            • USA

            #6
            Re: Sanyo DP50749 not switching on

            If it is a switched LDO the you will need to replace it with the same type, they put switched LDO due to the circuit is required to be powered up in sequence.
            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

            • dskall
              Badcaps Legend
              • Oct 2016
              • 2905
              • usa

              #7
              Re: Sanyo DP50749 not switching on

              Will keep looking for reg. It did power up from external power
              I assume no responsibility for any stupid suggestions I might post.

              Comment

              • Chuper
                Member
                • Sep 2017
                • 36
                • Canada

                #8
                Re: Sanyo DP50749 not switching on

                Ok, took a long time to get it from Korea but in my case ICQ805 (KIA78L15F) voltage regulator quit working. Replaced it and voilà TV is working again.
                Last edited by Chuper; 03-15-2018, 03:05 PM.

                Comment

                Related Topics

                Collapse

                • wnlewis
                  New wire for my RDE3340 Whirlpool electric range
                  by wnlewis
                  OK. I got the rocker switch figured out thanks to the good advice on this forum.

                  Now I need to figure out the correct wire to go to the switch from the broiler element and from the oven element.

                  This is a Whirlpool RDE3340 electric range.

                  The common wire on the switch appears to have a high temperature insulating material. I am guessing that both the wire to the broiler and the wire to the oven elements also need relatively high temperature insulation. What do I need to look for? The broiler is rated at about 2400 watts.

                  Where may I find parts...
                  01-08-2025, 11:21 PM
                • technicalspecialist
                  Vintage fan repair, copper wire question
                  by technicalspecialist
                  I currently have a customer's vintage fan on the work bench to repair.
                  It uses an induction motor with 4 poles. One of the poles is open.
                  I couldn't find the break so i cut off the original wire.
                  I have measured the other poles and the resistance is about 28 ohms per pole and I measured the diameter of the wire with my digital calipers and it is 0.35mm in diameter.

                  I need to work out how much 0.35mm diameter enamelled copper wire i need to order for it to be 28 ohms. I have used this calculator and it says i need 160.35 metres.

                  The enamelled copper...
                  03-16-2023, 12:54 PM
                • sam_sam_sam
                  Heater element wire type instead of a fuse when troubleshooting a short circuit DIY
                  by sam_sam_sam
                  I was Ollie today which is a close out / surplus outlet store I do not go in there to often because you find things that you should not be tempted by but that is a another story

                  I saw a small space heater that used a wire type of heater element which I been looking for a while but not really hard mind you but when I saw this I grabbed it I going to go back tomorrow and buy the last one that is like the one I bought today because I need the heater element and the ceramic insulators and more of heat element wire because this one has two different wattage settings one 1300 watts ( tap...
                  12-16-2023, 08:39 PM
                • SolomonMan
                  Nest Thermostat Discussion...
                  by SolomonMan
                  All,

                  I was over my sons place helping him with projects today. (Broken Dryer Belt, a Couple leaking pipes (One cracked - that got me over there),and Thermostat swap.

                  The Energy company offered a Rebate on the Nest Thermostat System (Not the Learning One) last year and we picked it up and its sat in the shipped box for about a year now.

                  Anyways I was thinking it would be a quick job as I currently have a Nest Learning Thermostat at my place and it was not a problem to install. (Old Rheem 90 Furnace)

                  At my boy's place he has a York Stellar...
                  12-11-2022, 10:54 PM
                • Topcat
                  Dell XPS 8950 Power Issue
                  by Topcat
                  A few months out of warranty and it's dead as a fart. XPS 8950 with a 12th Gen I5, 32gb DDR5 RAM and a GTX1650 GPU.....

                  Symptoms it's giving are really making a coin toss between bad motherboard and bad PSU....I'm leaning toward motherboard, but there are some strange irregularities with this piece of shit system.

                  Basic test:
                  Upon connecting power cord, system powers on by itself (no button push) for a second then powers down...and then powers back on again, I hear a relay trip inside the PSU, and then powers down again and that's it. It won't do anything else....
                  01-02-2024, 05:51 PM
                • Loading...
                • No more items.
                Working...