Qilive Q40FS21 after turn on revert to standy

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  • jorpec
    Member
    • Feb 2015
    • 32
    • Portugal
    #1

    Qilive Q40FS21 after turn on revert to standy

    I have this lcd tv after i turn it on, the Qilive logo appears on the screen then 2 seconds later revert to standby, first i thought it could be the led bars, if i disconnect the backlight the tv stays on, or if i leave the led bars connected but disconnect the screen the backlight stays on, then i power the backlight though a led tester i was able to see that the tv was working, then i go to menu and lower the backlight intensity to 10(from the min 0 to max 100) then connected the backlight again and the tv worked normally but when on the menu i raise the backlight intensity when reaching 64 the tv revert to standby again. It seems some current sensor trigger the shutdown
    What it could be ?
    The board is a CV6683H-E42 a all in one board power supply + control board

    Thanks

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    • Answer selected by jorpec at 06-23-2025, 07:03 AM.
      jorpec
      Member
      • Feb 2015
      • 32
      • Portugal
      Just to give a feedback, I found what was the problem, it was the current sensing resistor on the primary side of the power supply, the resistor should have 0,22 ohm, and had around 0,40 ohm
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        • jorpec
          Member
          • Feb 2015
          • 32
          • Portugal
          #2
          Just to give a feedback, I found what was the problem, it was the current sensing resistor on the primary side of the power supply, the resistor should have 0,22 ohm, and had around 0,40 ohm
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