Apple MacBook Pro 16-Inch 2019 - A2141 - stuck at 5V

[martyjelen]

Is this measurements ok?

[mon2]

What is the voltage to ground of SSD_PMU_RESET_L? If at 0v, continue to measure the following points of interest:

(in order of the power up sequence chart - report any that are at 0v; continue otherwise to check each)

P5V_3V3G3H_EN
PP3V3_G3H_T
P3V3MAIN_PGOOD
P5VG3S_EN
PP5V_G3S
P5VG3S_PGOOD
P1V8G3S_EN
P3V3G3S_EN

[martyjelen]

SSD_PMU_RESET_L - 1,8V

[martyjelen]

P5V_3V3G3H_EN -0V
PP3V3_G3H_T -3,3V
P3V3MAIN_PGOOD - 0V
P5VG3S_EN - 0V
PP5V_G3S - 3,3V
P5VG3S_PGOOD - 0V
P1V8G3S_EN - 0V
P3V3G3S_EN - 0V

[mon2]

Some of these measurements do not look correct. If you have a power rail then the _EN signals must be '1'. If you have the measured power rails then the _PGOOD should be '1'.

Review the following to double-check each:

[martyjelen]

Hello, sorry for delay.

PMU_PVDDMAIN_EN - 0V
P5V_3V3G3H_EN - 0V
P5VG3S_EN - 0V
P3V3MAIN_PGOOD - 0V
P5VG3S_PGOOD - 0V

[martyjelen]

PP3v3_G3H_SOCPMU (measured on C7893/C7869) - 3.3V

[mon2]

P5V_3V3G3H_EN -0V

Confirm the voltage to ground on each side of R7652.

Remove all power and confirm the resistance across R7652 which should be ~3k3 ohms.

[martyjelen]

0V on each side of R7652.
Resistance is about 3,2kΩ

[mon2]

What is the voltage to ground of PPBUS_G3H @ F7000 / F7001? Is it stable?

[martyjelen]

Both are exactly 12.3V/stable.

[martyjelen]

I also checked voltage on R7900 (I read on forum that sometimes this resistor is the problem.) There is 3.3V on both sides.

[mon2]

Confirm the voltage to ground on:

R6968 ; CHGR_EN_MVR_R / CHGR_EN_MVR

R6934 / R6935 ; PP3V3_G3H_RTC_REG_R / PP3V3_G3H_RTC_X

[martyjelen]

R6968 - 5.1V on both sides.
R6934 / R6935 - 3.3V on both sides.

[mon2]

Good. Onto steps 6 & 7.

[martyjelen]

PP3V0_G3H_RTC - 3V
PCH_CLK32K_RTCX1 - 0.5V

[martyjelen]

Should I continue with next measurements?

[mon2]

Yes.

[martyjelen]

Step 8 - PCH_RTC_RESET_L - 3V
Step 9 - PMU_XTAL1 - 0V / PMU_XTAL2 - 0.6V
Step10 - PP3V3_G3H_T - 3.3V
Step 11 - PP1V8_SLPS2R - 1.8V
Step 12 - PMU_CLK32K_SOC - 0.8V
Step 13 - PP1V8_AWAKE - 1.8V
Step 14 - PP1V8_SLPS2R_PMUVDDGPIO - 1.8V
Step 15 - PP1V1_SLPS2R - 1.1V
Step 16 - PP0V8_SLPS2R - 0.8V
Step 17 - PP0V82_SLPDDR - 0.8V
Step 18 - PP3V3 _AWAKE - 3.3V
Step 19 - PPVDDCPUSRAM_AWAKE - 0.8V
Step 20 - PP0V9_SLPDDR - 0.9V
Step 21 - P1V1_SLPDDR_SOCFET_EN - 1.8V! (is it OK?)

[mon2]

Step21 - this is the enable pin for the loadswitch @ U7901. The enable voltage can be different than the operating voltage of the switch.

Confirm the voltage to ground on U7901, pins #3 and #5. Are they stable @ 1v1 for each? Then this is ok.