820-00138 no ppbus_g3h

[Bunuffin]

Hello it's me again...

Got a board with liquid damage, it turns on with battery plugged and Yellow light.

Water damage was around U7100, replaced damaged components and the U7100.

U7100:
DCIN 20v
Pin 17/18 3ohm
Pin 19/20 5ohm
Pin 27/28 21ohm

PPBUS_G3H diode mode ok, but 0.8v

 

[2informaticos]

What about 3V42_G3H with charger alone (no battery connected)?

Post U7100 basic voltages; pins 1, 2, 3, 9, 12, 13, 14, 15, 17, 19, 20, 27.

 

[Bunuffin]

Sorry was on hollydays

1 - 3.4v; 2 - 20v; 3 - 4.8v; 9 - 0.04v; 12 - 3.4v; 13 - 3.3v; 14 - 3.2v; 15 - 0.05v; 17 - 0.63v; 19 - 5.5v; 27 - 20v

PP3V42_G3H - 3.4v

 

[2informaticos]

"PPBUS_G3H diode mode ok"
Can we get a real data?

Be sure C7125 is good; check its traces too.
May need to change Q7130/35 also.

 

[Bunuffin]

PPBUS_G3H =
Red probe on ground 0.45v
Black probe on ground 2.3v

Changed the C7125 (didn't work), checked the rails and OK...
We got delivered new U7100s, so I changed it and get 12.52v ppbus, but something strange is happening.

Fan spin but yellow light on without battery plugged in, battery with lightning appears on the display and it doesn't turn on, is that normal?

PS: probbed the battery connector and it does 12.52v for a couple of seconds, then it goes down to 4v for a second, then 0v and back to 12v in a loop

PPS: at the pin 4 of the Q7155 I can see the fluctuation, pin 16 of U7100, is that another faulty U7100?

 

[2informaticos]

Amber light on Magsafe is normal, without battery.

Low battery with lightning sign is caused by incorrect charger, I supposse.
Use original 85W charger.

 

[Bunuffin]

I am using a original 85w charger, but it was the battery, with another battery it turns on, thanks again for helping us