Macbook Air 820-00165 works only on battery.

[arshees]

Need help with a 820-00165 board. Runs perfectly fine on battery but the moment i connect the adapter cable it shuts down completely. I changed the DC board but still same behavior. I have a green light that turns yellow but no voltage on F7140 when connected to Adapter. 7.6v on F7140 on battery and boots up all the way. What direction do i move to begin with?

 

[2informaticos]

If board works on battery, you have a problem on input power stage.
Disconnect battery and tell us if get voltage at PPDCIN_G3H and PPBUS_G3H.

Check resistance between pins 17/18 and 27/28 of U7100.

 

[arshees]

PPDCIN_G3H - 16.5v
PPBUS_G3H - 0v
U7100 Pin 17/18 -3.45 ohms
U7100 Pin 27/28 - 20.40 ohms

 

[2informaticos]

Do you get 3V42_G3H on charger alone?
If not, check D7012 and R7005.
Post Q7010 voltages.

 

[arshees]

3V42_G3H - 16.1v
Q7010
Pin 1 - 16.5v
Pin 4 - 6.8v
Pin 5 - 16.52v
Pin 6 - 15.52v
R7005 - 10.3 ohms
D7012 seems fine too.

 

[2informaticos]

"3V42_G3H - 16.1v"
Do NOT joke; post accurate information, please!!!
U7090 voltages?
Also post for U7100, pins 1, 2, 3, 9, 12, 13, 14, 15, 17, 19, 20, 27.

 

[arshees]

Sorry my oversight...
3V42_G3H - 3.4v

U7100
Pin 1 - 8.5mv
Pin 2 - 16.22v
Pin 3 - 4.33v
Pin 9 - 58.3mv
Pin 12 - 3.41v
Pin 13 - 2.8v
Pin 14 - 3.3v
Pin 15 -51.5mv
pin 17 - 0v
Pin 19 - 5.06v
Pin 20 - 5.05v
Pin 27 - 16.1

U7090
Pin 1 - 1.9v
Pin 2 - 3.4v
Pin 3 - 7.2v
Pin 4 - 3.4v
Pin 6 - 16.1v
Pin 8 - 16.1v

 

[2informaticos]

Check/replace R7100, C7125 ans Q7130.
If still the same, replace U7100 too.

 

[arshees]

Replaced Q7130, C7125 and U7100. Got a fan spin and board up and working. Thank you.