MacBook Pro A1706 Notebook Does Not Recognize Hard Disk Repair

Machine model: apple MacBook Pro A1706
Main board number: 820-00239-A
Malfunction: the notebook does not recognize Nand.
Maintenance process:

Apple MacBook Pro A1706 laptop, appearance inspection,Nand VCC IC has been repaired.

MacBook Pro A1706 Notebook Does Not Recognize Hard Disk Repair figure 1.

Measure Inductor around Nand VCC IC U9300, and the output of VCC is normal. Dismantle the main control directly and reinstall it. Dismantle shielding cover and perform VCC on the main control.

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BGA Rework Station pry open the main control.

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Take care of pin, the main control place, and be careful with the vinyl.

MacBook Pro A1706 Notebook Does Not Recognize Hard Disk Repair figure 4.

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Handle pin of RAM.

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Take care of the lower level.

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Install the master control, and the test failure remains the same.

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Directly change the Nand master control; dismantle Nand; and deal with pin of Nand.