820-02020 one usb c 5v and one 20V

[kingskie]

hi all,

i am working on 820-02020 that confusing. this board has no water damage, all clean like new.

the problem is one usb port get 20v and the other one only 5v.
i replace the cd3217 related to the 5v and still no 20v to get.

measurements when get 5V
- LDO 3.28V
- both fuse 5V
- pp1v8_s2 pulsing from 1.8v and 0V
- ppbus on F5200 pulsing 12.2v to 8.7v

measurement when get 20v
- LDO 3.28V
- both fuses 20V
- pp1v8_s2 1.79v
- ppbus on f5200 11.9V

[mon2]

Re: 820-02020 one usb c 5v and one 20V

On the usb port that is stuck to 5 volts, flip the power adapter connector by 180 degrees during insertion.

Does this port now function at 20v ?

Each usb C port features a CCx communication line. This line is used to negotiate the power delivery contract. It is possible that the esd diode on the CCx line is damaged and halting the proper communication of the power delivery contracts. By flipping the power adapter head, you are exercising the other side of the USB C connector and testing the other CCx line but still validating the same ACE controller.

Next, remove all power.

Meter in DIODE mode.

Red meter probe, yes RED to ground.
Black meter probe onto CC1 line of the ACE controller stuck at 5 volt.

What is the reading?

Repeat for the CC2 line of the same ACE controller.

Compare the results to the working ACE controller side.

Suspecting that an ESD event is stopping the 20v power delivery contract due to a damaged esd diode on the CCx line(s).

[kingskie]

Re: 820-02020 one usb c 5v and one 20V

Hi @mon2,

On the usb port that is stuck to 5 volts, flip the power adapter connector by 180 degrees during insertion.

Does this port now function at 20v ?

Each usb C port features a CCx communication line. This line is used to negotiate the power delivery contract. It is possible that the esd diode on the CCx line is damaged and halting the proper communication of the power delivery contracts. By flipping the power adapter head, you are exercising the other side of the USB C connector and testing the other CCx line but still validating the same ACE controller.

Next, remove all power.

Meter in DIODE mode.

Red meter probe, yes RED to ground.
Black meter probe onto CC1 line of the ACE controller stuck at 5 volt.

What is the reading?

Repeat for the CC2 line of the same ACE controller.

Compare the results to the working ACE controller side.

Suspecting that an ESD event is stopping the 20v power delivery contract due to a damaged esd diode on the CCx line(s).

Hi @mon2,

On the usb port that is stuck to 5 volts, flip the power adapter connector by 180 degrees during insertion. --> still get 5V

What is the reading?
USBC0_CC1 = 6.3M ohm
USBC0_CC2 = 6.3M ohm
Repeat for the CC2 line of the same ACE controller.

Compare the results to the working ACE controller side.
USBC0_CC1 = 6.0M ohm
USBC0_CC2 = 6.0M ohm

[mon2]

Re: 820-02020 one usb c 5v and one 20V

These are resistance readings.

[kingskie]

Re: 820-02020 one usb c 5v and one 20V

These are resistance readings.

yes it is resistance reading. if you asking about continuity mode, i checked there is no short on both lines for 5V and 20V as well

[kingskie]

Re: 820-02020 one usb c 5v and one 20V

i try to plug in charger through 20v usb and the macbook turn on but only shows exclamation logo on lcd

[kingskie]

Re: 820-02020 one usb c 5v and one 20V

update:
tried to dfu mode to connect with apple configurator but nothing happened.

any suggestion?

[mon2]

Re: 820-02020 one usb c 5v and one 20V

Review this webpage:

https://support.apple.com/en-us/HT201314#internet

[kingskie]

Re: 820-02020 one usb c 5v and one 20V

Review this webpage:

https://support.apple.com/en-us/HT201314#internet

still cannot do recovery mode. i think this macbook can not do dfu mode because M1 macbook must use usb c near lcd to connect but since that usb c is only draw 5v it cannot do dfu mode.