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HP L2045w white screen problem

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    HP L2045w white screen problem

    I got a HP L2045w monitor when I turn it on the LED turns green and I get a white screen, I cant get to menus.

    I took it apart and looked at, the electrolytic can caps, cables,5v power rail, they all were good. Except the main fuse on the LCD controller board.

    The ground and supply rails are shorted on the controller board. I know this because the resistances are ~5Ω. When I bridge the fuse I hear a clicking sound coming out of the main board like a fuse is blowing then resets.

    I repaired a HP LP1965 monitor with the same problem, it was a shorted ceramic capacitor.

    So i started desoldering the ceramic capacitors,and diodes, using a hot air rework station. Then I desoldered the FET transistor which when I resoldered it made the resistances go up from ~5Ω to ~1kΩ. When I Bridge the fuse with a strand of copper wire, the board still shorts out.

    I recorded resistance values of the test points after I resoldered the FET
    Back of the board
    VCOM= 20MΩ
    VDDD= 1.034kΩ
    VDDG= 100KΩ
    VEEG= 147.2KΩ
    VDDA=0.884KΩ
    V1= 0.875KΩ
    V2= 0.873KΩ
    V3= 0.776KΩ
    V4= 0.749KΩ
    V5= 0.729KΩ
    V6= 0.629KΩ
    V7= 0.639KΩ
    V8= 0.566KΩ
    V9= 0.491KΩ
    V10= 0.416KΩ
    V11= 0.375KΩ
    V12= 0.315KΩ
    V13= 118.6Ω
    V14= 48.6Ω (this seems really low)

    I took pictures of the circuit board
    • green is the components i tested
    • red is positive*
    • Black is negative*
    • blue is potentially bad components
    • purple is the blown fuse
    • yellow is a FET transistor that i desoldered

    *most likely this is wrong so don't trust it.







    Also there is a Photoshop file which overlays the front and back layers
    https://trpxsg.bay.livefilestore.com...ownload&psid=1


    Any help would be appreciated,
    Thanks
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