820-3536 Not Charging Battery

[brunomotter]

Hello. This board came from another store and had been cleaned previously, so I don't know where original damage was. Board was liquid damaged but all traces of liquid had been erased by cleaning. Board turns on, works on battery and on charger, but does not charge battery. Magsafe light comes green and orange but system says battery is not charging. Tried with another known good battery, same thing. Tried reballing SMC, same thing. R5380 and 5381 are ok, both reading 2k. R5187 reads 100k. Battery sensing resistors from ISL both read ok(R7151/52) and so do R7121/22. R7150 also good. Where else should I check?

 

[2informaticos]

Exact PPBUS_G3H voltage, without battery connected?
Also post voltage and diode mode to ground readings at SCL/SDA lines of battery bus.
Be sure R7050 is good; SYS_DETECT_L must be 0V.
Check Q7155 and its traces.

 

[brunomotter]

I confess I didn't check PPBUS_G3H before as machine was turning on. But after you asked I tried turning board on outside the case and it didn't, so I checked PPBUS and it's giving only 1.156V. I have no shorts there, so I replaced U7100 and Q7130, but still same weird voltage on PPBUS.

 

[brunomotter]

Q7180(which I already replaced before) was bad and preventing PPBUS to get high. Replaced it and now everything is working again. Thanks!