820-00239 no power

[Mamdouh]

Hi, i have a Macbook pro Touch Bar that has no power, no sign of liquid damage, 3 of the 4 usb c ports are working and take 20v at 0.04amps the last usb c doesn't take any power.
PPBUS_g3h is 13v
pp5v_s5 is 5v
3v3_g3h is 3.4v
3v3_s5 is 0v with 0ohms to ground 3v3_sus is not present
do i need to follow the short first or figure out why one of the usb c isn't working

 

[2informaticos]

All USB-C ports should have the same behaviour.
But go first for the short on 3V3_S5.
No reason to solve USB-C problem, to find shorted CPU at the end.
Disconnect trackpad and any other cables and check again for short.

You can try injecting voltage into 3V3_S5.
Start with 1V, no more than 4V.
If there is really short, you should find the culprit with less than 2V; 20A lab PSU may be required.

 

[Mamdouh]

I injected 2.5 volts at c7667 went up to 3 amps and nothing got warm, how many amps would be safe to go up to, i am checking with a thermal camera, any recommendations or should i try with more amps

 

[2informaticos]

Remove CPU heatsink first.
Don't forget to set PSU amp limit to max!
And start with lower voltage.