820-4924 charger problem.

Alan.L

Member
initially, the board couldn't see the original apple charger but works well with PSU/fake charger.
so I changed Q1780 and it still didn't work then I changed ISL and works for a few hours with original apple charger but later on, it stops working.
then I changed Q1780 and ISL at the same time in case it will kill ISL or Q1780 but it still not working.
then i changed Q1780, ISL, SMC and now it is working, passed ASD and can charge the battery with no problem

with a fully charged battery, sometimes the charger's green light goes out. i'll have to turn off the charger from the mains then turn it on then i get a green light.

with charger only
------------------------
PPBUS_G3 = 12.58v
PP3V42 = 3.399V

with battery
------------------------
PPBUS_G3 = 12.75v
PP3V42 = 3.399V

with battery and charger
------------------------
PPBUS_G3 = 13v
PP3V42 = 3.399V


Resistance on 17/18, 27/28 OF ISL. = 4 ohms, 20 ohms
Resistance to ground on the DC-in fuse = 68.1k ohms
 
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2informaticos

Moderator
Staff member
Check Q/D7010.
Measure (onboard, ohm scale) exact value for R7012.
Post CHGR_A/BMON voltage when it doesn't want to start.
Does it always start in SMC bypass mode?
 

Alan.L

Member
R7012 = 67.9k ohm
D7010 and Q7010 are present. i don't see anything wrong with them.

starts up fine, I've never used SMC bypass mode on this board.

with a 100% charged battery and charger connected, when the MagSafe's light is green
CHGR_AMON = 0.092v
CHGR_BMON = 0.054v
PP18V5_DCIN_fuse = 16.49v

with a 100% battery and charger connected, when the MagSafe's light goes out
CHGR_AMON = drop from 0.092v to 0.031v to 0v
CHGR_BMON = 0.054v
PP18V5_DCIN_fuse = 0v

mmm just notice..
the green light will come back on repeatedly when I wait 2 minutes after the green light fades out.


do you think there could be a broken trace?
 

2informaticos

Moderator
Staff member
"PP18V5_DCIN_fuse = 0v"
Seems that charger detects leakage and get blocked.
Try the machine with Original Apple 60W and also 85W and comment.
Apple chargers have a microprocessor which detects leakage.
Fake chargers always send out full voltage, no protection at all.
This is the reason machine always starts with fake charger; same happens with bench power supply.

"R7012 = 67.9k ohm"
Did you measure onboard?

Check D7012 voltage.
Post exact value (onboard measured) for R7180/81 and R7185/86.
 

Alan.L

Member
what do you mean by onboard, with power?
i thought you are not supposed to measure a resistor with the power on.
my resistance measurements are done with the components are soldered on the board.

-----------------------------------------------------

D7010:
original 85w charger plugged-in with green light = 6.79v
original 85w charger plugged-in when the green light disappeared = 0v


R7180 = 99.4k ohms
R7180 = 61.15k ohms
R7185 = 469k ohms
R7186 = 331k ohms


-----------------------------------------------------

just tested with another palm-rest with genuine battery. it's same.

i'll try 60w next..
 
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2informaticos

Moderator
Staff member
Of course no power when measure ohm, or diode mode.
I just specified to measure components onboard, not removed.
Because this kind of measure intents to discard other components, apart of the tested one.

Are you using Magsafe 1 --> 2 adapter?
Do NOT do that!
 

Alan.L

Member
did that already, i'am now testing with a 60w magsafe2 original, so far so good. need more testing,

if 60w is ok, then where is on the logic board i need to look?
 
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Alan.L

Member
ok. i can confirm a 60w original MagSafe2 is fine, the green light always stays on. any idea how to fix an 85w original MagSafe 2 issue?

I've already replaced every component on the Q7010 area,
 
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