820-000165 red light no fan spin, no waterdamage

[ppvout.s0]

Dear,

I try to read from other Threads, but I see to get stuck.

C7582 was short. Removed and replaced. After that laptop worked fine. But after 10 seconds the same Talanoium Capacitor was short again.

Now I removed C7582 and there is no fan spin no boot.

The light charger is red without batterij.

I read from other threads

U7100
Pin 19 Diode mode = 0.456V (red probe on pin 19)
Pin 19 Diode mode = 2.3V (black probe on pin 19)
Pin 20 Diode mode = 0.456V (red probe on pin 19)
Pin 20 Diode mode = 2.3V (black probe on pin 19)

U5110
1 = 3.4v PP3V42_G3H
2 = 0v
3 = 3.5v
4 = 2.2v

8 = 3.3v
7 = 3.4v
6 = 3.4v
5 = 3.4v

Any help would be appreciate

 

[2informaticos]

"I read from other threads
------------
Pin 19 Diode mode = 0.456V (red probe on pin 19)"
Where did you read to measure diode mode with black probe on ground???

HOW TO collection

I hope this "How to" collection will help our members. I will possibly modify this post in time, if updates available. Trigger SMC_ONOFF_L (PMU_ONOFF_L): It reffers to simulate power button function, when the keyboard is not connected. We need to do this when we work with the board...

boards.rossmanngroup.com

BTW, stop to write the end "V" when you post diode mode readings.

"after 10 seconds the same Talanoium Capacitor was short again"
Did you really check no short to ground on PPBUS_G3H after removing C7582?
Why did you suspect the new capacitor, to remove it?
Didn't use one with similar nominal voltage???

 

[ppvout.s0]

Thanks for reply Amigo:
There is no short to ground on PPBUS_G3H I have a steady 8.59v
C7582 was shorted, I know how to find shorts with my DC power supply. Just to stupid for diode mode. Hope to learn from you.
C7582 was burning on my FLIR camera on 4amps 1v. I removed and the short was gone. System booted. Just not so long.


I replaced C7582 from a donar board.

Where my readings oke from U5110?

 

[2informaticos]

U5110 looks good.

You've said to read threads here; where did you see ANY mention to inject voltage into PPBUS_G3H BEFORE checking for high-side MOSFETs???
Don't you really like to work more carrefully, putin logic in your job?

"I know how to find shorts with my DC power supply"
Doesn't look like...
You was very lucky to get same cap shorted, not a CPU MOSFET; do NOT force your luck!
A simple ohm check shows you if is safe to inject voltage; do not tell 1V didn't risk anything.

Do you get now 3V3_SUS/S5?

 

[ppvout.s0]

Angry teachers is most likely to learn fast.

Keep screaming. I learn twices as fast.

PP3V3_S5 = 3.3
PP3V3_SUS = 0.001

Sorry, i Guess it was not so smart to inject AMPS.

 

[2informaticos]

You didn't inject amps, but voltage.
You cannot control voltage and current at such time!
Ohm law is very clear...

You have missing PM_SLP_SUS_L probably.
Are you using original Magsafe 2 charger?
Post SMC_ADAPTER_EN, PM_BATLOW__L, PM_DSW_PWRGD, PCH_DSWVRMEN and all PCH's RTC signals.

 

[ppvout.s0]

SMC_ADAPTER_EN = 3,4
PM_BATLOW_L = 1,0
PM_DSW_PWRGD = 1,0

the rest i need to see what is all that.

 

[2informaticos]

"the rest i need to see what is all that"
Didn't read all the above mentioned link?

"PM_BATLOW_L = 1,0
PM_DSW_PWRGD = 1,0"
Both bad.
Check S5_PWRGD.

 

[ppvout.s0]

Studing very fast.

Angry teacher is the best!

Why do many MacBook Air 820-00165 show red light without a battery attached?

 

[2informaticos]

ALL Magsafe 2 machines have the same behavior...

 

[ppvout.s0]

It just randomly went on after going deeper.

Is it possible to leave S5_PWRGD out? Or would it make the system very unstable?


With BAT only it won't turn on.

On Q7155 with battery only connected
Pin 5 = 7.8
Pin 1,2,3 = 0
Pin 4 = 0

On Q7155 with battery and Charger connected
Pin 5 = 7.8
Pin 1,2,3 = 8.4
Pin 4 = 8.2

 

[2informaticos]

Q7155 is bad, change it.
Guess what internal diode does there...

 

[ppvout.s0]

It should protect the board from getting to many current in? Lets say when a wrong battery is attached?

I don't get how the same Q7155 works both ways, for charging and for suppling current when DCIN is disconnected.

Oke, all working now!

 

[2informaticos]

Q7155 lets the current to flow directly from battery to MLB, when no charger present.
It didn't that in your case...

 

[ppvout.s0]

thanks for your answer.

TO/FROM BATTERY it says.

So how this Diode also charge the battery? Looks like one-way only right?

 

[2informaticos]

"current to flow directly from battery to MLB"
This is EXACTLY what its internal diode does; no matters if MOSFET is open, or not.
To charge the battery (MLB to battery), the MOSFET must be turned on.