akai lct3285ta power on issue

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  • craigc15
    Senior Member
    • Jun 2012
    • 53
    • USA

    #1

    akai lct3285ta power on issue

    I've been troubleshooting this TV for too long and I could use some help.
    I replaced all bulging caps on the PS, but I have this weird situation that I thought I had overcome, but now it's back.
    The standby light comes on, but when you hit the power button, the red standby LED blinks but that's it. I don't have the schematic, but I happened across a remedy, that had now failed, too. I was able to get the set to power up by putting a 50 ohm resistor across the 5VSB supply and that worked for a week, or so, but now it's back to the original problem.
    I wasn't crazy about the kludge, but it worked, until now.
    Any thoughts on what might be happening here?

    Thank you!
    Craig
  • tom66
    EVs Rule
    • Apr 2011
    • 32560
    • UK

    #2
    Re: akai lct3285ta power on issue

    What capacitors did you use as replacements?
    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

    • craigc15
      Senior Member
      • Jun 2012
      • 53
      • USA

      #3
      Re: akai lct3285ta power on issue

      I didn't replace all of them, the guy that gave the TV to me must have replaced them.
      I just replaced the 3 - 1000uf in the 5VSB supply with 3- 1800uF and it turns on fine now, even without the resistor!
      Now I just have to figure out why the buttons/remote don't work consistently, and why it stays stuck in "DTV Initial". I can't select "DTV" in the menu to set up the digital tuner.
      Any idea what might be causing these problems?

      Thank you VERY much Tom. You seem to be the only person out there offering help, so it's much appreciated.

      Craig

      Comment

      • craigc15
        Senior Member
        • Jun 2012
        • 53
        • USA

        #4
        Re: akai lct3285ta power on issue

        Well, it was nice while it lasted, but now it's back to not coming on.
        The 5VSB goes wild when I press the power button. I was able to get it to come back on by putting a 2o ohm load across the 5VSB. I even turned it off and back on without the load.

        I am using Panasonic low esr caps.

        HELP!

        Comment

        • tom66
          EVs Rule
          • Apr 2011
          • 32560
          • UK

          #5
          Re: akai lct3285ta power on issue

          What series of capacitor did you use? Ultra low ESR can cause problems too -- the cap needs to be low ESR but not too low (i.e. motherboard grade.) 2 ohm is also much too high of a load on 5Vsb.
          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

          • ben7
            Capaholic
            • Jan 2011
            • 4059
            • USA

            #6
            Re: akai lct3285ta power on issue

            The little capacitors 10uf to 47uf commonly go bad too.
            Muh-soggy-knee

            Comment

            • budm
              Badcaps Legend
              • Feb 2010
              • 40746
              • USA

              #7
              Re: akai lct3285ta power on issue

              "I just replaced the 3 - 1000uf in the 5VSB supply with 3- 1800uF" Are they all connected in parallel? That is a lot of capacitance from 3000uf to 5400uF.
              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

              • craigc15
                Senior Member
                • Jun 2012
                • 53
                • USA

                #8
                Re: akai lct3285ta power on issue

                Essentially, they are in parallel. They're part of a pi filter: 2 before an inductor and 1 after. I just thought I'd experiment. I'll put the 1000's back in.
                This set is a lower priority. I'm dealing with some others right now and then I'll go back to this one.
                I'll post an update when I have more info.

                Thanks!

                Craig

                Comment

                • craigc15
                  Senior Member
                  • Jun 2012
                  • 53
                  • USA

                  #9
                  Re: akai lct3285ta power on issue

                  Thanks Ben!
                  One of the 10uf caps in the 5 volt PS section was bad. Turns on great now.

                  All that I need to do now is figure out why the buttons and remote don't work for the first 5-10 minutes.

                  Comment

                  • panzerpat
                    New Member
                    • Oct 2013
                    • 1
                    • usa

                    #10
                    Re: akai lct3285ta power on issue

                    Hello,

                    I'm working on the same kind of tv, I already replaced all the power board capacitors 3 days ago and it worked fine (although it took a good 4 mins. to start)
                    Now today all of a sudden the red light is blinking again and it won;t turn on for anything..
                    Anybody got any ideas?

                    I used this kit to repair the powerboard;

                    http://www.ebay.com/itm/230840928125...84.m1497.l2649

                    Comment

                    • lzep
                      New Member
                      • Jan 2014
                      • 3
                      • USA

                      #11
                      Re: akai lct3285ta power on issue

                      Hey there craigc15, did you ever discover the solution to your issue regarding the remote not working for several minutes after turn on. I am having the same problem.

                      Comment

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