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A2442 820-02098 5V

I

iMuhtaseb

Member
Came in with a little teeny tiny speck of dust on U9300 and R9310 resistor above it.
Removed the chip, cleaned it up and install new resistors and few caps around it.. still 5V..
I took few measurements
PPDCIN 5V (diode mode good according to OBD)
PPBUS 12.27V (diode mode good according to OBD)
PP3V8_AON 3.8V (diode mode good according to OBD)
PP1V8_AON 1.8V
PP5V_S2_MAIN was 2.9v and unstable goes up and down.. (diode mode: 0.406, it seems good as well)
I took off U9300 suspecting maybe its pulling 5V S2 down.. but still 5V S2 was fluctuating..
To save time I changed UC260 (5V S2 VR) directly.. and still 5V S2 was fluctuating..

I measured the enable signal (P5VS2_PWR_EN) and it was low (0.550v) and unstable as well.. and it comes from MPMU U8100..
I measured IPD_PWR_EN_PMU and it was absent.. IPD_PWR_HOLD was absent too.

5VS2_PWR_EN diode 0.714
IPD_PWR_EN_PMU diode 0.714
IPD_PWR_HOLD diode 0.692

I don't want to blame U8100 directly and since I need to order these chips and it requires a lot of time.. is there anything else I need to checkup? something I looked over?
 
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I

iMuhtaseb

Member
This board after one month has returned.. customer complained the screen turned grey then it shut off.
I've received the computer, the board takes 5V 0.01-0.08A
PPBUS 12.3V
PP3V8_AON 3.8V
PP1V8_AON 1.8V
PP5V_S2_MAIN 5.1v
PP1V8_S2 1.8v

U9300 should produces three power stages and they're present at 2.5v
P1V8VDDH_DRMOS_PWM1 & P1V8VDDH_DRMOS_PWM2 & P1V8VDDH_DRMOS_PWM3

PP1V8_S1_CLVR_VDDH 1.8v

U8100 bucks were present except for PPVDD_AVEMSR_AWAKESW was missing on all coils and on both sides.

PPVDD2H0_S2SW is present at 1v
 
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2informaticos

2informaticos

Administrator
Staff member
All USB-C ports have the same behavior?
Tested disconnecting internal LCD?

Check if machine can complete DFU revive.
 
I

iMuhtaseb

Member
"All USB-C ports have the same behavior?"
yes exactly

"Tested disconnecting internal LCD?"
I'm testing bare board

"Check if machine can complete DFU revive."
It won't go into DFU
 
I

iMuhtaseb

Member
Forcing is by wiring SOC_FORCE_DFU to SOC_FORCE_DFU_DBG based on the test pads on board is that correct or have I gotten it wrong?
If yes then it won't go DFU either
 
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I

iMuhtaseb

Member
Ok, I didn't know that I was doing it wrong.. can you please give be a brief steps since I've read logi and it confused me even more. Sorry for troubling you.
 
I

iMuhtaseb

Member
The picture you're mentioning is for the M1 MacBook Air which has a different layout than the 14" MacBook Pro A2442.

I spoke to Alexey to to get the numbers and orientation of the board correct for M1 Pro.

Anyways, I have now 1.25v in SOC_FORCE_DFU still not going into DFU.. I tried bare board and I tried in housing with battery and charger plugged in same results not getting into DFU..
 
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