T2 and CD3217 Power on Sequence

If a CD3217 does not have the LDO outputs, test the lines for shorts, otherwise the chip is missing power or bad. Data sheet of closest Ti chip.

A bad CD3217 can often cause a loop at step 10. All of the CD3217s need to be fully functional and communicate with the SMC before the CD3217 connected to the charger will request 20V

These documents are for specific boards, but will likely apply to most T2 Mac. Any net names and designators will be specific to the board it is from.

820-01055

820-01598

T2 Power rails resistances (820-01700)

PPVDDCPU_AWAKE 10-15 Ohm

PP0V82SLPDDR 30-40 Ohm

PPVSSCPUSRAM_AWAKE 100-120 Ohm

PP1V1_SLPS2R 1-2 kOhm

PP0V9_SLPDDR 40 Ohm

PP1V8_SLPS2R 4 kOhm