Help 42lf651 suspect backlight fault

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  • Rickig
    Senior Member
    • Mar 2015
    • 112
    • England

    #1

    Help 42lf651 suspect backlight fault

    Hi all
    I have acquired this set 42lf561 that was sold to me has having a duff bavklight
    However when powering on the set it looks as the the back light is on but dim. (All the others I've fixed you'd struggle to see the image, this one not so) see pic.

    Before I start stripping down the set just wondering if anyone has had a similar issue
    and point me in the right direction

    Thanks
    Attached Files
  • dick_barton
    Badcaps Legend
    • Aug 2015
    • 6642
    • Wales

    #2
    Re: Help 42lf651 suspect backlight fault

    Have the backlights in the menu been turned to far down?

    If you could post pictures of the circuit boards and how they interconnect would be useful.

    I would start by measuring the led voltages at the connector since the set is working but backlight dim. It could also be the dimming level set low.
    Willing to help but I'm no expert.

    Comment

    • Andrew F. Ali
      Badcaps Legend
      • Jan 2014
      • 2450
      • Trinidad & Tobago

      #3
      Re: Help 42lf651 suspect backlight fault

      Backlights seem to be working but at low voltage. I am not certain if there is a high resistance that developed in the LED Driver circuit or if just a few strings in the LED array are working and some off. The only way to tell IMO is to open up the Panel and use a LED Tester to power-test each string.

      Comment

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