A1708 820-00840-A not charging

[hgoncalves]

Hi,
I have an A1708 820-00840-A that works fine, but does no charge the battery (only works with charger connected), and down't know where to start.

Already tried with a known good battery.
The battery is recognized but stays at 0%.

U7000 looks normal.
R5381 = 1.98 kohm
R5380 = 1.99 kohm

SMBUS_SMC_5_G3H_SCL = 3.4V
SMBUS_SMC_5_G3H_SDA = 3.4V
PPBUS_G3H w/o battery 13V

Can you help?

 

[2informaticos]

Diode mode to ground at SCL/SDA lines?
R6950 is good?
Battery big screw correctly tighten?
Data cable connected OK?

Post PPBUS_G3H and 3V42_G3H levels with battery only.

 

[hgoncalves]

Hi,

R6950 = 9.9 kohm

Diode:
SMBUS_SMC_5_G3H_SCL = 0.474V
SMBUS_SMC_5_G3H_SDA = 0.474V

PPBUS_G3H =11,15V

I can't find 3V42_G3H. Is it right?

 

[2informaticos]

Sorry, is 3V3_G3H...

 

[hgoncalves]

OK.
3V3_G3H = 3.4V

 

[2informaticos]

Did you try known good working battery, or just "new"?

 

[hgoncalves]

I've tried with a new one, but that works on other mac.
PPBUS_G3H, with charger connected, is flutoating bettween 13.00V to 11.15V, and keeps for ever with this behavior (with both batterys)

 

[2informaticos]

So original battery also works in other similar machine?

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (only battery).

 

[hgoncalves]

Hi,
Tks.
After all, it seams that the problem was the data cable connecting the battery to the board, that had some kind of problem. With a new cable, the problem stoped.
Tks!