820-3662 doesn't charge the battery

[BCN_Techs]

Hi!
There was spill in the U7100 and U7501 area, so I replaced the two ICs and some components around them. Now the macbook can start and work (fans spin very fast), but it does not charge and puts "repair" in the battery state. The charger led blinks green twice, stays steady for 1 second and blinks twice again.

PS: I also tried two batteries and same result.

 

[2informaticos]

Tried known good battery?

Check voltage and diode mode to ground at SCL/SDA lines.
Post exact PPBUS_G3H voltage w/ and w/o battery connected?
Run corresponding EFI ASD test.
Check R7150/51/52 and traces; also check SMC_CHGR_BMON_ISENSE level.

 

[BCN_Techs]

SCL = 3.40V
SDA = 3.40V
PPBUS_G3H W= 10.80V
PPBUS_G3H W/O = 19.54V

EFI ASD = tomorrow (I'm downloading the files).

R7151 = 2.8 ohms
R7152 = 0.8 ohms
SMC_CHGR_BMON_ISENSE = 45k / 0V

 

[2informaticos]

"PPBUS_G3H W/O = 19.54V"
If this means PPBUS_G3H without battery (only charger), Q7130 is shorted; change it asap.
Be sure C7125 is good.

 

[BCN_Techs]

I have injected V = 1V into PPDCIN_G3H_CHGR and R7021 / 2 was getting hot: I changed the resistors, changed Q7130 but it still doesn't charge the battery (R7021 / 2 no longer gets hot).

With thermal camera, Q7130 heats up with charger and charger + battery.

 

[2informaticos]

Did you think to check actual PPBUS_G3H voltage???

 

[BCN_Techs]

PPBUS_G3H = 19.20V.

 

[2informaticos]

Doesn't look to high for you?
Change Q7130...

 

[BCN_Techs]

I have changed it 3 times but it remains the same, it doesn't charge the battery and it gets hot (Q7130).

 

[2informaticos]

Did you check PPBUS_G3H each time?
Be sure Q7130 Gate pin has good contact with U7100.
Also check/replace C7125; its traces good?

 

[BCN_Techs]

Thanks to @2informaticos for the information: I have managed to get ppbus to be correct (12.58V) and to charge but, I still have problems: when turning on the macbook, the battery appears after 1-2 minutes of logging in (charger connected) and when I disconnect the charger, it keeps marking as if it was charging.

 

[2informaticos]

Did you try known good battery?
Check SMC_BC_ACOK when charger is disconnected; only battery present.

 

[BCN_Techs]

Yes, it's a new battery with 1 charge cycle.

SMC_BC_ACOK = 0V (battery connected only).

 

[2informaticos]

New chinese battery?
You've said tried two more batterires; was any known good?

 

[BCN_Techs]

Newertech battery.

Yes, I have an "old original" battery and this new one.

 

[2informaticos]

And known good one has exact the same behavior?
Did you try another original Magsafe 2 charger?

 

[BCN_Techs]

Yes, it recognizes it after 1-2 minutes of logging in.
With the new battery, I can turn on the macbook but still, it recognizes it after 1-2 minutes and even if I charge it, the percentage doesn't change (I look at the information about the remaining charge and after a few minutes, I check again).

Yes, I have tried with another original magsafe 2 and same behavior.

 

[2informaticos]

Remove internal SSD and try another USB macOS.
Or try with the SSD from another working machine.

Do PRAM reset 2-3 times.
Actual PPBUS_G3H, without battery?

 

[BCN_Techs]

I finally changed the SMC and the battery issues were fixed.

It can be marked as repaired and thank @2informaticos