Macbook air 820-3023-A no green light

stephsa

New member
When I plug the power cable there are curent on ppbus g3h and the 3v42 was also here. but the green light not be there ?
I change the u6900 but no change. The 3v42 (3v39 in real) was on the u6900 but the green light don't turn on . Why ??
please to help me :)
 

dukefawks

Administrator
Known good IO board and flat cable are also a good place to start. But PPBUS voltage can tell a lot too.
 

aprendiz

Moderator
SMC is not running, check if SMC_RESET L is present, if yes, check diode mode on SMBUS_SMC_BSA_SCL and SMBUS_SMC_BSA_SDA, this could be a bad ISL6259 or a bad SMC...
 

stephsa

New member
voltage on u5010
1 3.39v
2 ground
3 3.39v
4 2.65v
5 0.68v
6 0.69v
7 106mv
8 0.33v
 
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dukefawks

Administrator
Those readings are all sorts of weird. Pin 8 is a simple regulator output and should be 3V, pin 6 should also be high. Are you sure this is correct? Seems like U5100 could be dead or corroded trace to pin 1 or 3.
 

stephsa

New member
Ok i changed the u5010 and now it boot :)
thanks ! ;-)
BUT now the power button don’t works. All keys are working. So I think the button not is the real problem. I used a ssd from a mbp so perhaps it is that because the mbp have is button not on the keyboard ????
 

dukefawks

Administrator
All keyboard have the same pinout. You can even use a separate keyboard from a macbook pro. Any macbook keyboard will be ok for testing.
 

stephsa

New member
I have used the touch’s on the circuit for the power on and it doesn’t work ! So it is not the keyboard ?
 

dukefawks

Administrator
Check continuity from power on pads to R5070. If OK then remove U5010 and do a diode mode reading on the power on pads.
 
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