820-00850 No power - 20V 0.400 slowly ramping to 1.6A

[ronaldo]

Hi, I need help with this Mac.
The trackpad is clicking.
The only components showing signs of heat are the T2 chip and the battery coil.
There's no short on the coils, and diode mode is normal.
PPBUS_G3H - 12.6V
SLP2 and AWAKE voltages are present.
NAND power rails are at 0.9V, 1.8V, and 2.5v.

I've attempted to revive and restore the Mac, but it fails every time.
The error message indicates that the Mac has been forced into DFU mode externally.
AC2 flickers and returns to DFU a few seconds before the error appears.
The voltage is unstable on all lines, and the signal on all four CD3217 - USBC_XA_CC1 varies from 0.8V to 1.2V.

Thanks in advance.

 

[2informaticos]

Any fault history available?
Tried DFU with 61/87W charger and charged battery connected?

 

[ronaldo]

The customer stated that it was purchased second-hand / refurbished.
I tried to revive with a 87w charger, and the battery charged, but it got stuck on installing the system.

 

[ronaldo]

Do you think the CPU is gone?

 

[2informaticos]

Try DFU keeping 3V3_S5 tied to ground.
This will prevent Intel side to power up.

 

[ronaldo]

Tried that and it did not work. Same as before.