Emerson LED LF551EM5 Chirping/Beeping Transformer?

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  • mikeyd
    Member
    • Jun 2016
    • 21
    • USA
    #1

    Emerson LED LF551EM5 Chirping/Beeping Transformer?

    I have this tv here and when i try to power it on, the standby light blinks and there is a chirping sound coming from what seems like a transformer. The blinks correspond with the chirps. I have 168V on my smoothing cap on the hot side, and when I try to power it on and the chirps begin, I have 290V. I have an ESR meter and I tested all my caps and they seem ok. I'm not super familiar with how to read ESR though. I also checked for shorts and I cannot find one.

    I have only the main board connected to the PSU because I couldn't figure out how to turn on the PSU without the main board.
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    • mikeyd
      Member
      • Jun 2016
      • 21
      • USA
      #2
      Re: Emerson LED LF551EM5 Chirping/Beeping Transformer?

      Pin 4 has 3.3v until the set is on
      Pin 5 has 3.3 only on
      Pin 6 has 3 only on
      Pin 7 has 3v on then drops to 0v
      Pin 8 has 3.3v off and 3v on
      Pin 15,16,17,18 has 7.7v off and 12 on
      Pin 20,21,22,23 has 13.9v off and 21 on

        Comment

        • mikeyd
          Member
          • Jun 2016
          • 21
          • USA
          #3
          Re: Emerson LED LF551EM5 Chirping/Beeping Transformer?

          After some more poking around on the PSU, I found this guy shorted. I can't seem to find a replacement part though.
          Attached Files

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            • goontron
              5000!
              • Dec 2011
              • 4108
              • US
              #4
              Re: Emerson LED LF551EM5 Chirping/Beeping Transformer?

              Logo looks like Pericom Semiconductor. AKA: Diodes INC

              Where was it on the board?
              Last edited by goontron; 10-15-2016, 11:25 AM.
              Things I've fixed: anything from semis to crappy Chinese $2 radios, and now an IoT Dildo....

              "Dude, this is Wyoming, i hopped on and sent 'er. No fucking around." -- Me

              Excuse me while i do something dangerous


              You must have a sad, sad boring life if you hate on people harmlessly enjoying life with an animal costume.

              Sometimes you need to break shit to fix it.... Thats why my lawnmower doesn't have a deadman switch or engine brake anymore

              Follow the white rabbit.

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