Re: 820-00850 with shorted LDOs

Thanks again.

Here are the readings:
USBC_TA_CC1 = 0.57 V (takes time to stabilize)
USBC_TA_CC2 = 0.48 V (takes time to stabilize)
USBC_TB_CC1 = 0.61 V
USBC_TB_CC2 = 0.61 V
USBC_XA_CC1 = 0.60 V
USBC_XA_CC2 = 0.60 V
USBC_XB_CC1 = 0.61 V
USBC_XB_CC2 = 0.61 V

Definitely different. So diodes QB630 and QB640 have also gone bad?

Thanks for the pointer to the Wiki. This is the page I used to start troubleshooting but I stopped measurements at step 2 when I saw all LDOs...

Re: 820-00850 with shorted LDOs

Thanks for the lightning fast answer mon2.

I will look at vendors with good feedback to source the replacement CD3215C00 then.

Do you think it is worth checking for other components that might have been damaged now or is it better to wait until I have replaced the faulty CD3215?

Hello all,

I am trying to repair one of my relative's dead 2018 MacBook Pro A1989. It stopped charging all of a sudden but was still working on battery until it was depleted.

It shows the following symtoms:[LIST][*]Power on 3 of the USB-C ports cycles from 5V 0.25 A to approx. 1A[*]On the 4th USB-C power stays at 5V 0.25A but if I flip the USB-C power plug the meter does not light up[/LIST]

UB300 is the CD3215 associated with the 4th port. There is no visible damage around UB300 or the port itself.

I checked PP20V_USBC_TA_VBUS and it is stable...

Re: New Members - please post your introductions here

Hello all,

I am a tinkerer from France who loves retrotech and helping family members/friends by doing small repairs of their equipment.

Thank you for creating this great resource!