PANASONIC THP42U20A main board issues

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  • chrismurphy
    Badcaps Veteran
    • May 2014
    • 251
    • australia
    #1

    PANASONIC THP42U20A main board issues

    I have this main board issue with this panasonic tv
    The TV powers up with steady green light no blinks , but no screen activity , all voltages on SC and SS boards are ok
    suspected the main board , so i reflowed both chips on the board and now i get screen ok and picture ok no issues , but no sound . When i press the volume up button the TV shuts down . Any ideas ??
    Tags: None
    • happyade123
      Senior Member
      • Feb 2015
      • 92
      • Australia
      #2
      Re: PANASONIC THP42U20A main board issues

      Maybe leakage in the front panel buttons. Try disconnecting it and turn on and do volume up with remote . I know you probably know a lot more then me but just a suggestion Chris.
      Last edited by happyade123; 12-31-2017, 05:46 AM.

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        • R_J
          Badcaps Legend
          • Jun 2012
          • 9535
          • Canada
          #3
          Re: PANASONIC THP42U20A main board issues

          Check that the speaker wires are not pinched or touching the chassis somewhere, you may have a problem with the audio output chip.
          Do you have the schematic? Check sos signal on D2014 or `C' of Q2301, does it change when vol up is pressed
          Do you have s_15v on L2301 or L2302
          Last edited by R_J; 12-31-2017, 10:33 AM.

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