Air A2179 820-01958-A

[lincev]

Hello, I need help with this board. It worked correctly but my brother forgot the charger. I tried to connect it to a hotel USB port to charge it and it didn't turn on again.

I have checked it under a microscope but I don't see any burned or damaged components with the naked eye. With another laptop if the apple configurator detects the presence of this board.

thanks to all

 

[2informaticos]

We need some voltage readings at least...

 

[lincev]

omg! sorry



values only with charger (without battery):

PP3V3_G3H - 2,96v
PP5V_G3S - 5v
PPVIN_G3H_P5VG3S - 12,5v
PPVIN_G3H_P3V3G3H - 12,5v
PPBUS_G3H - 12,5v
PPBUS_HS_CPU - 12,5v

 

[2informaticos]

"PP3V3_G3H - 2,96v"
Which pin of L7690?
Did you check diode mode ground too?

Is the machine recognized into DFU mode?

 

[lincev]

L7690 pin1 3,26v

mode ground any short´s at PP3V3_G3H, PP5V_G3S, etc..

The Apple configurator detects the board in lock mode (locking logo) but cannot put it in DFU mode.

 

[2informaticos]

So 3V3_G3H is correct.
Remember to always check voltage on the output pin of a coil from any buck-converter!

Try to force the machine in DFU with wire method.

 

[lincev]

ok try this, sorry I can't see ur answer.

I wanted to try to recover the information but I see that there is no solution

thx to all

 

[lincev]

Good morning, macbook in dfu mode restore load operating system and halfway (approximately) restart and cancel then I can see logo "padlock"

I try this 3 times and 2 cables usb-c genuine

cpu dead?

 

[2informaticos]

USB ports switch to 20V?
Did you test the board alone on the desk?