Macbook Air 820-00165 not work from adapter and works on battery

isc

New member
when AC adapter connected fan not spain and charging led turns to red without attaching battery , when battery is attached charging led go to green and macbook works ,when i remove battery mac still working , in other hand macbook boot up and ssd not recognized and cpu temperature is so high.
video describe the situation

video note: customer said that macbook falled down .

video her google drive
 

2informaticos

Administrator
Staff member
First of all, welcome to the forum!

Don't play again connecting disconnecting battery, when charger is plugged in.
You risk to fry the SMC; do NOT force your luck.

If Magsafe light switch to green, when battery is connected, can mean fully charged battery, or a problem with charging battery circuit.

The board MUST turn on by itself, when charger is connected (without battery).
So do not connect battery again, until fix this.

Post exact ohm resistance between pins 17/18 and 27/28 of U7100.
Also post U7100 voltages; pins 1, 2, 3, 6, 9, 12, 13, 14, 15, 17, 19, 20, 27.
Use surrounding components as test points.
 

isc

New member
Thanks for your reply

Resistance between pins
17/18 2.4 ohm
27/28 14.9 ohm.

U7100 voltages; pins
1, 0
2, 14.37
3, 3.88
6, 0
9, 0
12, 3.41
13, 3.38
14, 3.38
15, 0
17, 8.58
19, 8.58
20, 5.02
27. 14.37
 
Last edited:

2informaticos

Administrator
Staff member
OK, so you get correct PPBUS_G3H on charger only.
Now check PM_BATLOW_L, 3V3_S5/SUS, PM_RSMRST_L, PM_PWRBTN_L, PM_DSW_PWRGD, PCH_DSWVRMEN.

Do NOT quote an entire previous post, visible few centimeters above.
Instead of cliciking "Reply" button, write directly in the reply box.
Please, maintain forum aesthetic...
 
  • Like
Reactions: isc

isc

New member
ALL TESTS ON AC ADAPTER ONLY


PM_BATLOW_L --- 0.03

PP3V3_S5 --- 3.33

PP3V3_SUS --- 3.23

PM_RSMRST_L --- 3.30

PM_PWRBTN_L --- 3.41

PM_DSW_PWRGD --- 3.41

PCH_DSWVRMEN ---- 3.23
 

2informaticos

Administrator
Staff member
"PM_BATLOW_L --- 0.03"
PCH cannot start power on sequence in this condition.
Are you using original Magsafe 2 charger?

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L, at same time.
Try to start in SMC bypass mode also.
 

isc

New member
Yes I use original charger and test other charger but the same situation
When I trigger SMC_ONOFF_L pulse of PM_PWRBTN_L drop from 3.41 to 0.34 but no boot up fan not spin

IT STARTS NORMALLY FROM BATTERY BUT NOT DETECTS SSD.
I APPLIED SMC RESET AND PRAM RESET BUT NOT BOOT FROM CHARGER
 

isc

New member
I check it 10k ohm and fin connected to surrounding components and the impedance between PM_BATLOW_L and ground is about 3M Ohm, also i check PP3V3_S4 transistor Q3000 no problem.
 

Attachments

Last edited:

isc

New member
Also PM_BATLOW_L control by pch may be cpu chip defective?
note: mac can boot from battery but ssd not be detected and temperature of cpu is very high and fan full speed spaining.
 

Attachments

2informaticos

Administrator
Staff member
PM_BATLOW_L is controlled by SMC; PCH uses it as input.
An internal problem of PCH can affect this line, but is less probably.

Fan starts at full speed, or increases speed as CPU gets hot?
SSD is not detected at all in Disk Utility?
 
  • Like
Reactions: isc
Top