Macbook Pro M2 820-02773 5v 0A

[luckydip]

Working on this macbook, showing 5v 0A from charger - dead. Board is clean - no liquid, owner said he left it charging and died. Some voltages:



After looking at board closely found L8430 damaged/blown open circuit so replaced it. No change, still 5v 0A - I'm thinking over current on L8430 (PP3V8_AON_MPMU_ISNS_VIN) killed U8100?

Tried connecting to another macbook but not in DFU mode. Forced DFU points have very low volatge so haven't bothered with that.

Any other ideas?

[luckydip]

Forgot to say - no shorts on major power rails including PP3V8_AON_MPMU_ISNS_VIN, L8430 hasn't blown since replacement. Also noticed another coil L7700 (PP3V8_AON_SPMU_ISNS_VIN) is slightly wonky but reads fine and 3.8v on both sides.

[mon2]

Remove all power -> meter in resistance mode -> measure the resistance to ground of:

PP1V8_AON (created by J16 of U8100)

Measure the voltage to ground of:

I2C_SMC_PWR_1V8_SCL
I2C_SMC_PWR_1V8_SDA

U5200 (ISL9240) is not getting boosted which occurs over the above I2C lines. If 1v8 is missing, then gathering this is the reason for this voltage PPBUS_AON to be not boosted to ~13 volts by the SMC.

[luckydip]

Thanks for the reply.

PP1V8_AON resistance to ground 455k diode 435mV

Voltage

I2C_SMC_PWR_1V8_SCL 574mV
I2C_SMC_PWR_1V8_SDA 578mV

So does 1v8 come from U8100 or somewhere else?

[mon2]

Yes, U8100 appears to be the creator of this power rail. Confirm the presence and conditions of L8230 and also R8230. This power rail is not shorted, yet is not working.

U8100 may be defective. Any visual defects on this part?

[luckydip]

L8230 and R8230 both visually ok and have continuity

U8100 appears clean and undamaged but I have a suspicion that it may have been fried with a over current pulse when L8430 was blown

Once again, thanks for taking the time.