Sharp 40BJ3K - Backlight immediately dims and turns off.

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  • stav242
    Senior Member
    • Jan 2014
    • 61
    • United Kingdom
    #1

    Sharp 40BJ3K - Backlight immediately dims and turns off.

    Model : Sharp 40" 4K LED 40BJ3K with TP.MS6586.PC710 single board.

    Fault: Turning on TV, the backlights come on then immediately start dimming down and turns off.

    Checks:
    Standby LED voltage starts at 46v
    checked all LEDs, all test good.
    Checked caps, diodes and most for shorts.
    Nothing obvious.

    (Edit)
    Ok so since getting the board out to photo, and testing all components in place (as a first pass). I reinstalled the board ,reseating all connections to the PCB... And the backlight is now working...

    Active LED voltage rises to 75v.

    TV seems to function normally... Will soak test it for a bit but seems ok now.
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