polaroid 704 tablet backlight and power issues

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  • cadillacman
    Badcaps Veteran
    • Feb 2011
    • 524
    #1

    polaroid 704 tablet backlight and power issues

    A friend gave me this to tinker with. WHen powered on, works fine for a few minuites, then the backlight starts to blink off and back on,.. first slowly and over time more in succession untill it flashes rapidly, then shuts off. At that point the tablet is totally dead and wont even connect to a pc via the usb port. Let it cool down, same deal works untill its warmed up. It will talk to a usb port when first powered on. I did notice one section with tiny transistors or ldos gets extremely hot, i guess i need to get some pics and post but these components are TINYYYYYYYyyyyyy..

    Does anyone know where the heck i can buy a new or used mobo for this thing?

    or maybe i just need to try to fix it... who knows. THis is all new to me im used to changing caps etc.
    Tags: None
    • ben7
      Capaholic
      • Jan 2011
      • 4059
      • USA
      #2
      Re: polaroid 704 tablet backlight and power issues

      Since this is a tablet, I am guessing the backlight is led, right? If so, my guess is a bad led!

      Could we have some pics, and point out the very hot transistor(s)?
      Muh-soggy-knee

        Comment

        • cadiman
          Badcaps Veteran
          • Mar 2010
          • 397
          #3
          Re: polaroid 704 tablet backlight and power issues

          I have worked on every tablet made just about, but not a polaroid.

          All of the led tablets backlight runs on 5 to 12voltdc.

          I have never had one fail.

          I use them to backlight pumpkins, doll houses and school projects.

          I use the batteries for hobby projects.

          Sounds like you have a battery issue more than a backlight problem.

          These smaller tablets do have battery charging issues and should use a switching power supply.

          I had to buy special glasses to work on these.
          Last edited by cadiman; 04-08-2013, 05:19 PM.

            Comment

            • cadillacman
              Badcaps Veteran
              • Feb 2011
              • 524
              #4
              Re: polaroid 704 tablet backlight and power issues

              once i figure out how in the heck to get pics this small, i will post some.

                Comment

                • cadiman
                  Badcaps Veteran
                  • Mar 2010
                  • 397
                  #5
                  Re: polaroid 704 tablet backlight and power issues

                  I have worked on all the coby and toshiba entry level tablets for all the small kids to beat up on.

                  They have all moved up to Apple so I fix all of that stuff now.

                  More money to be made and parts are abundant too.

                  It`s all Dr. Shepard...Brain surgery...not always 100% outcome.

                    Comment

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