A1278 820-3115-B not charging

hgoncalves

Active member
Hi,

I have an A1278 820-3115-B that is not charging.

I have 12.55V on PPBUS_G3H w/o battery, and 8.96V with battery connected.

Diode readings:
SCL= 0.543
SDA= 0.536

R5281= 1,979 ohms
R5280= 1,996 ohms

Already removed D6950 but same result.

Can you help?
 

2informaticos

Administrator
Staff member
"8.96V with battery connected."
Battery alone (no charger)?

Did you try disconnecting BIL?
Is the battery recognized by macOS?
Tried known good battery?
 
Last edited:

hgoncalves

Active member
Hi,

8.96V with battery, and charger connected. W/O charger 11.19V

Now I'm testing it with just the board on the bench, and w/o BIL

The battery isen't recognized on the macOS, and alreay tried a known good battery.
 
Last edited:

hgoncalves

Active member
R7000 it's OK.

I've replaced U7000, but PPBUS_G3H is increasing voltage with battery connected. Started at 8.9V and now is at 11V. Shouldn't it be decreasing?
 

2informaticos

Administrator
Staff member
With charger and battery connected, PPBUS_G3H slowly increases when battery is charging.
Once battery is fully charged, PPBUS_G3H should go to 12.5V and Magsafe light switches from amber to green.
 

hgoncalves

Active member
HI,

I'm going to replace the SMC.

Strangly, it seams that the battery is charging, but the mac don't work with battery alone. If I unplug the charger power cable, it loses image, the the fan keeps spining (witch indicates that it has battery). It seams that it hibernates when the charger is unpluged, because if i plug the power again, un push the power button, it is still in the desktop.

PPBUS_G3H increased at 12.5V, but the battery isen't recognized in the OS...
 

hgoncalves

Active member
I've replaced the SMC and now it charges the battery, but only withou the LID connected. Is there any way to solve this?
 

2informaticos

Administrator
Staff member
SMC_LID is 3V with BIL connected?
Check SCL/SDA lines w/ and w/o BIL connected; voltage and diode mode to ground.
 
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