MacBook A1989 BT/WLAN Issue, Questions, or Replacement Requests

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  • EvilSnowtech
    New Member
    • Dec 2023
    • 1
    • 中国香港特别行政区
    #1

    MacBook A1989 BT/WLAN Issue, Questions, or Replacement Requests

    Hello members of the repair forum,

    I'm facing an issue with my MacBook A1989, where I encountered a short circuit on PP1V8_G3S for reasons unknown. After removing the audio amplifier and MIC, the resistance values returned to normal.

    However, during testing, I found that attempting to enable Bluetooth yields no response. Bluetooth cannot be activated, and the PP1V8_G3S-to-ground resistance value is approximately 285. I suspect that PP1V8_G3S_WLANBT_VDDIO may, under certain conditions, exceed 1.8v, potentially causing damage to the Bluetooth module. I am considering replacing it.

    Since the A1989 features a T2 chip, I haven't found any relevant information about Bluetooth addresses in the T2 ROM. I'm wondering if it's possible to transfer components from another motherboard, replacing the Wifi module U3730, BT ROM U3750, and Wlan ROM simultaneously. Or is it sufficient to only replace the Wifi module U3730?

    Does this process involve any T2-related unbinding procedures?

    I am genuinely puzzled by this issue and eagerly await your response. Thank you very much!
    ​
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