No image on Macbook A1278 which is 820-3115

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  • mnciks11
    Badcaps Veteran
    • Aug 2019
    • 345
    • south Africa

    #1

    No image on Macbook A1278 which is 820-3115

    The laptop turns On and give the chime sound, meaning the CPU is working 100%, but i have no image on the screen.


    U9000 have 3.3v for data line on the input side but 0v on the output, i knew that there was nothing wrong with U9000 since it was not being told to turn on, anyway i reomved the chip with another same one but still no 3.3v

    L9004 has 0v
    L9008 has 3.3v
    L9080 (The double Choke/coil) has ov on one side and 1.8v on the other side
    pin 21 and 22 (PPVOUT_SW_LCDBKLT) has 12v
    pin 8 up to 15 for data we have 0v

    one more thing, the bios chip on pin number 5 and 6 i get no voltages there, literal i have 0v on pin 5 and 6 of the bios

    guys please share your ideas im lost now, i dont have any short to ground on the screen connector

    kindly find attached picture
    Attached Files
    Last edited by mnciks11; 06-24-2020, 07:37 AM.
  • piernov
    Super Moderator
    • Jan 2016
    • 4435
    • France

    #2
    Re: No image on Macbook A1278 which is 820-3115

    Originally posted by mnciks11
    L9080 (The double Choke/coil) has ov on one side and 1.8v on the other side
    Please clarify
    OpenBoardView — https://github.com/OpenBoardView/OpenBoardView

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