My THIRD Insignia NS-32LCD!!

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  • Paul678
    Badcaps Veteran
    • Nov 2011
    • 402
    #1

    My THIRD Insignia NS-32LCD!!

    I was hoping this was going to be yet another simple power supply
    issue like the last two, but it was not to be.

    This time I used my oscilloscope to check the +24DCV and +5V,
    to make sure they were stable, and they were.

    The backlight was not working, even with the +24V there, but the
    "BLON" (back light on) pin was at zero volts, so I jumpered
    this pin to +5V using a 1k ohm resistor, and the lamps turned
    on, working just fine, but the screen was a blank black screen,
    because the main board wasn't displaying anything, no menu
    or anything.

    So it's pretty clear it's a main board issue:



    "BLON" (back light on) pin is on the white connector on the right most, bottom
    corner. I measured some of the resistors in the lower right corner at +3.3V, but there
    were also some areas that measured a weird +16V. WTF??????

    But most of the advice here is for SMPS, inverters,
    fuses, and caps, but not so much advice for fixing
    main boards, so I ain't holding my breath, but just
    in case someone knows something about this board,
    I'm naturally all ears......

    But it looks like it's Ebay time, yet again!

    Last edited by Paul678; 12-04-2012, 04:46 PM.
    Tags: None
    • tom66
      EVs Rule
      • Apr 2011
      • 32560
      • UK
      #2
      Re: My THIRD Insignia NS-32LCD!!

      There are several DC-DC converters and voltage regulators. I have had the DC-DC converter fail on a similar Harwa chassis, which caused the TV to lock up then not power on after being turned off.
      Please do not PM me with questions! Questions via PM will not be answered. Post on the forums instead!
      For service manual, schematic, boardview (board view), datasheet, cad - use our search.

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