I am working an a MBA 13 2020 that has no display. The MacBook power on but no display. After Checking on the backlight I found out that the EDP_BKL_EN was missing. And this power enable was coming from the PCH. So that means this MBA board is no chance to bring it back to life? any suggestion would really appreciate. Thanks, MobileXt
A12179 820-01958 Missing EDP_BKLT_EN
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Re: A12179 820-01958 Missing EDP_BKLT_EN
Locate R0550 and measure the voltage on pin # 2. This is only to confirm that the trace for EDP_BKLT_EN is not broken from the PCH to the target.
Then remove all power, measure the resistance to ground of pin # 2 of R0550.
What is the reading ? Is it the same ~86K ? The resistor is a 100k value but perhaps while in circuit, the reading of 86k is normal.Comment
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Re: A12179 820-01958 Missing EDP_BKLT_EN
Locate R0550 and measure the voltage on pin # 2. This is only to confirm that the trace for EDP_BKLT_EN is not broken from the PCH to the target.
Then remove all power, measure the resistance to ground of pin # 2 of R0550.
What is the reading ? Is it the same ~86K ? The resistor is a 100k value but perhaps while in circuit, the reading of 86k is normal.
Diode Mode @ .528V
R0550 reading at 89.2KComment
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