Sony Brava KDL40s4100 - Dead, No Standby

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  • Nola_Gal
    Member
    • Sep 2013
    • 18
    • United States

    #1

    Sony Brava KDL40s4100 - Dead, No Standby

    Hey there guys, it's been a while since I've picked up another tv project, so It's time to consult the experts yet again.

    By the way, this forum has been a huge help to me in the past year. I really appreciate all the great advice & knowhow everyone has shared. Y'all rock!

    Today, I found a Sony Brava KDL 40S4100 (2008) on craigslist. The guy took great care of the tv, almost perfect cosmetic condition with the stickers still on. Original remote.

    The problem:

    According to the owner, the unit started to get slower and slower at turning on. The owner would unplug it, replug it, and turn it on. This worked for a while until it finally petered out.

    (To me, this sounded like something I might be able to fix. Power supply... Hopefully just some bad caps, so I went and got it.)

    It has no power at all. I plugged it in, pressed the power button manually. No clicking, no blinking, no sound, no standby.

    Opened the tv. No sign of any blown caps here, though I haven't taken the cover off of the A board yet. The fuse near the power supply is fine, reading '1'. Is anyone familiar with this model & maybe a common culprit for this particular problem?

    I checked the forum threads for the model in question. Everyone who posted with problems, had standby power to the unit. Nothing similar.

    I am by no means a tech or a pro, but I love taking things apart and figuring them out. I've fixed maybe 10 tvs. Trying to work smart here & get some good advice first. And again...
  • holmzy
    Senior Member
    • Nov 2009
    • 99

    #2
    Re: Sony Brava KDL40s4100 - Dead, No Standby

    chech standby v. should be 3.3v. if no standby bad psu if yes bad av main. thats my experience

    Comment

    • capkid
      Badcaps Legend
      • Oct 2010
      • 1339
      • United States

      #3
      Re: Sony Brava KDL40s4100 - Dead, No Standby

      Sonys are notorious for bad main boards. The 4100 series is no exception.
      LG Plasma Mal-Discharge Correction Service

      Comment

      • Andrew F. Ali
        Badcaps Legend
        • Jan 2014
        • 2450
        • Trinidad & Tobago

        #4
        Re: Sony Brava KDL40s4100 - Dead, No Standby

        The fuse near the power supply is reading '1'??? If it is good and your DMM is on 200 Ohm scale. It should read '0' if the fuse is good. If on the continuity/diode scale the buzzer should sound if the fuse is good, too.

        Comment

        • holmzy
          Senior Member
          • Nov 2009
          • 99

          #5
          Re: Sony Brava KDL40s4100 - Dead, No Standby

          usually if there is power goes through the board but no standby etc it might be the big resistors with the built in fuse. had a old model sony that went out that way

          Comment

          • capkid
            Badcaps Legend
            • Oct 2010
            • 1339
            • United States

            #6
            Re: Sony Brava KDL40s4100 - Dead, No Standby

            I should have read through the issue more closely before I responded. I would guess that the caps in the PSU are fine, since Sony's are fairly reliable in that department (of course, testing would confirm). It does sound like a PSU problem. "1" on the meter normally means there's an open aka bad fuse in this case. Does the meter have fresh batteries?
            Last edited by capkid; 06-02-2014, 11:04 AM.
            LG Plasma Mal-Discharge Correction Service

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: Sony Brava KDL40s4100 - Dead, No Standby

              Check the DC Voltage right at the two legs of the main filter cap (450VDC rating cap) to see if you have about 165VDC or not.
              Which power supply board do you have?
              http://www.shopjimmy.com/catalogsear...ony+KDL40s4100
              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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