Insignia NS-43D420NA20 backlight on no display - LCD panel burn failure

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  • howardc64
    Badcaps Veteran
    • Jun 2017
    • 634
    • United States
    #1

    Insignia NS-43D420NA20 backlight on no display - LCD panel burn failure

    Eventually discovered a burn mark near lower corner of LCD. Here is a summary
    • Backlight on, no image
    • Disconnect right buffer board (view from front), left side display comes on
    • Masked off pin 7+8 (both ~12,5v on both left and right buffer board) from t-con to right buffer board (view from front) display works but have some lines
    • Buffer board is pretty simple
    Removed the front bezel to examine edge of the glass. Found burn mark on lower right (view from front). Plastic bezel covering the burn mark region shows heat signature on the inside surface facing the LCD panel. Last 2 pics. Bright spot above burn mark on LCD is just flashlight reflection getting the area lit for pictures.

    Since the panel is defective, only salvage parts.

    Click image for larger version Name: IMG_4680.jpg Views: 0 Size: 2.80 MB ID: 3680343 Click image for larger version Name: IMG_4678.jpg Views: 0 Size: 4.21 MB ID: 3680344 Click image for larger version Name: IMG_4677.jpg Views: 0 Size: 2.60 MB ID: 3680342 Click image for larger version Name: IMG_4679.jpg Views: 0 Size: 4.44 MB ID: 3680345 Click image for larger version Name: IMG_4681.jpg Views: 0 Size: 3.77 MB ID: 3680352 Click image for larger version Name: IMG_4682.jpg Views: 0 Size: 4.38 MB ID: 3680353 Click image for larger version Name: IMG_4686.jpg Views: 0 Size: 3.79 MB ID: 3680354 Click image for larger version Name: IMG_4687.jpg Views: 0 Size: 4.06 MB ID: 3680349 Click image for larger version Name: IMG_4688.jpg Views: 0 Size: 3.56 MB ID: 3680355 Click image for larger version Name: IMG_4689.jpg Views: 0 Size: 4.06 MB ID: 3680348 Click image for larger version Name: IMG_4693.jpg Views: 0 Size: 2.28 MB ID: 3680351 Click image for larger version Name: IMG_4694.jpg Views: 0 Size: 2.16 MB ID: 3680350
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    Last edited by howardc64; 07-11-2025, 04:10 PM.
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