Macbook A2485 ( Main 820-02100-A) no power

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  • robgerr
    Senior Member
    • Apr 2012
    • 70
    • Italy

    #1

    Macbook A2485 ( Main 820-02100-A) no power

    Good morning.
    This MacBook came to me with the defect that it doesn't turn on, even the green or orange LED doesn't turn on from its power supply with magsafe connection. While disassembling the motherboard I noticed the following problems:
    UG400 with a hole, I desoldered it.
    I find very low resistance to ground on the LG801 coil. I unsolder UG800 and the short disappears. With these two components desoldered, I connect the magsafe and the light turns on orange but still doesn't start. I order a new Ug400 and UG800 but nothing changes, same problem. I check the components under the protective plastics and find the burnt protective plastic on the UH700. I remove the component but nothing changes yet. When connected to USB type C it negotiates 5V and absorbs 0.02A. If instead I connect to the right side USB port there is 5 V but 0 absorption.
    what can I check?​

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