Macbook Pro 14" A2442 820-02098-a

[obelix24]

I have this macbook pro that is not turning on.

taking 5V 0,05a on USB-C meter.

PPBUS_AON - stable 12,33V
PP3V8_AON - stable 3,8V

Strange thing is that when battery is connected and i connect USB-C charger it shows 5V then when i disconnect and reconnect it' doesn't turn on USB-C meter at all (i have to disconnect and connect battery)

I've checked and PPBUS_AON or PPVBAT_AON_CHRG_REG are not shorted to ground.

any idea how to proceed ?

[mon2]

Connect the USB-C charger (only). No battery. Measure the voltage to ground on each pin of the battery connector. Post each measurement.

[obelix24]

measuring just board (nothing connected) on J5151

SYS_DETECT_L - 0V
SMBUS_BATT_SCL - not stable 0,3 - 0,4V
SMBUS_BATT_SDA - not stable 0,3 - 0,4V

[mon2]

SMBUS_BATT_SCL - not stable 0,3 - 0,4V
SMBUS_BATT_SDA - not stable 0,3 - 0,4V

These are not good measurements and may denote an issue. Remove all power. Meter in DIODE mode. Red meter probe to ground; yes ground.

Black meter probe to point to test.

Test the above 2 lines of interest using this diode mode:

SMBUS_BATT_SCL
SMBUS_BATT_SDA

[obelix24]

In diode mode both 0,542

[mon2]

These lines are not shorted but may only be missing the pull up voltage. Hunt for the 2*pull up resistors on these lines. Then carefully confirm the voltage on the pull up resistors. Is it present? If not, remove all power. Measure the resistance to ground of the pull up voltage rail. We are checking if the pul up voltage rail is being shorted.