Trouble with Emerson LC407EM1

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  • Josh04217
    New Member
    • May 2016
    • 2
    • USA
    #1

    Trouble with Emerson LC407EM1

    Hi, I have an LC497EM1 that will power on, then display "Digital Television" then go black.
    I removed the main board and discovered 8 bad caps so far.
    I have a multi tester, some soldering skills and tools, a variable power supply.
    I've repaired a few tv's and other things, either by replacing boards or by replacing capacitors and a couple diodes. I know how to test diodes and capacitors, sort of grasping transistors and resistors. I guess I'm just wondering if anyone has seen this before, and if it's indicative of worse than a few bad caps. Cheapest I can find the board is for 70, so it's worth 20-30 in parts and a couple hours to me, otherwise buying the board and throwing it together in 5 minutes sounds attractive.
    Would appreciate any ideas or input, thanks in advance.
    Tags: None
    • dick_barton
      Badcaps Legend
      • Aug 2015
      • 6643
      • Wales
      #2
      Re: Trouble with Emerson LC407EM1

      Have you looked at the screen with a torch to see if there is an image on it as you press menu to see if it's just the backlights switching off.
      Have you measured the voltages going to the leds?

      Some nice sharp pictures would help.
      Willing to help but I'm no expert.

        Comment

        • dick_barton
          Badcaps Legend
          • Aug 2015
          • 6643
          • Wales
          #3
          Re: Trouble with Emerson LC407EM1

          I think there may be a circuit diagram for the set in a previous thread

          Edit:
          I'm not 100% sure but is this the schematic for your set.

          https://www.badcaps.net/forum/showpo...7&postcount=17
          Last edited by dick_barton; 05-19-2016, 03:47 AM.
          Willing to help but I'm no expert.

            Comment

            • CapLeaker
              Leaking Member
              • Dec 2014
              • 8327
              • Canada
              #4
              Re: Trouble with Emerson LC407EM1

              Shine a flashlight into the screen. I wonder if the TV actually keeps on running and just the backlight turns off. I would look at the inverter board and check those transformers to be within 3% tolerance.

                Comment

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