TCL 75R615 - no picture but working backlight & sound

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  • apnar
    New Member
    • Jun 2022
    • 4
    • USA

    #1

    TCL 75R615 - no picture but working backlight & sound

    Hello all! New to TV repair and trying to bring a TCL 75R615 back from the dead. I've tried to do my basic research/reading but am at a loss so thought I'd see if anyone had some suggestions.

    The TV powers up and I can see the backlight on. I can hear sounds by navigating the remote.

    I tried disconnecting each side of the LVDS cables one at a time, powering off for a while between, and it didn't change anything. So my first guess was the TCON board so I order a replacement and swap that in. Didn't change anything.

    Next I thought I'd try swapping the main board, same thing no improvement.

    I've poked the TCON board a bit with a multi-meter and see ~12v on both sides of the fuse and on the 5 contact points on top left of bottom left connector.

    I've attached pics of all the boards. Would love some suggestions on what to try next. Thanks!

    TLDR: no picture, back light and sound working, swapped both TCON and main boards to no avail. any ideas?
    Attached Files
  • dskall
    Badcaps Legend
    • Oct 2016
    • 2905
    • usa

    #2
    Re: TCL 75R615 - no picture but working backlight & sound

    I don't know. Possibly they may need to be paired up.
    I assume no responsibility for any stupid suggestions I might post.

    Comment

    • nomoresonys
      Badcaps Legend
      • Jan 2013
      • 12086
      • U.S.

      #3
      Re: TCL 75R615 - no picture but working backlight & sound

      seems like a tcon issue, wonder if you got a bad one or a mismatch, you did match up the numbers on the white stickers right?
      Last edited by nomoresonys; 07-22-2022, 01:02 PM.

      Comment

      • apnar
        New Member
        • Jun 2022
        • 4
        • USA

        #4
        Re: TCL 75R615 - no picture but working backlight & sound

        Originally posted by dskall
        I don't know. Possibly they may need to be paired up.
        Thanks, can you explain what you mean by "paired up"?

        Comment

        • apnar
          New Member
          • Jun 2022
          • 4
          • USA

          #5
          Re: TCL 75R615 - no picture but working backlight & sound

          Originally posted by nomoresonys
          seems like a tcon issue, wonder if you got a bad one or a mismatch, you did match up the numbers on the white stickers right?
          I got as close as I could reasonably find. See the two attached pics, original boards next to new installed boards.

          From everything I've read I thought it was icon board as well, guess there is a chance I got a bad one as a replacement too. Ordered from TV Parts Today because they seemed to have the closest match to the board. Is there another place you'd recommend trying or think I should try getting another one from them?
          Attached Files

          Comment

          • nomoresonys
            Badcaps Legend
            • Jan 2013
            • 12086
            • U.S.

            #6
            Re: TCL 75R615 - no picture but working backlight & sound

            probably see if they have another they can send you, most legit places don't have a problem sending out another if you send the first one back.

            Comment

            • CoryF
              New Member
              • Jul 2023
              • 3
              • United States

              #7
              Re: TCL 75R615 - no picture but working backlight & sound

              apnar do you happen to have any high resolution photos of the back of the power supply board? My TV recently stopped working and I was able to find some components that were blown, but there is a small resistor on the back side (R402) that has a hole blown right through the part marking. Hoping I can find the size in a high resolution image.

              Any help you can provide would be appreciated, thanks in advance!

              Comment

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