820-01700 No power 20V 0.07A no battery. 20V 2.5A with battery

[ronaldo]

Hi guys.
I need help, please. Need data on this.
Trying to fix this MacBook Pro (16-inch, 2019), but no success.
Customer stated that before it dies was boot looping and sometimes stuck on Apple logo.
With battery, it draws 20V and 2.5A. Without 20V 0.07A.
Trackpad clicking, no display.
On Apple configurator 2 it starts on Recovery mode.
Revive option on DFU mode no success, it failed with error:
The operation couldn’t be completed. (AMRestoreErrorDomain error 9 - Failed to receive message from device, might be connection problem with USB host.) [AMRestoreErrorDomain – 0x9 (9)]

I'm using original thunderbolt 3 cable.

Under thermal camera only T2 is getting hot.
No resistance between PPBus_G3H and NAND.
L9580 to Ground 4.7OHMs
Can't find any short.
Tried to disconnect internal display and run on external and same results.

PPBUS_G3 → 12.7V
CHGR_EN_MVR → 5.12V
PP3V3_G3H_RTC → 3.38V
PP1V8_SLPS2R → 1.8V
PMU_CLK32K_SOC_R → 0.89V
PP1V8_AWAKE → 1.79V
PP1V8_SLPS2R_PMUVDDGPIO → 1.8V
PP1V1_SLPS2R → 1.10V
PP0V8_SLPS2R → 0.79V
PP0V82_SLPDDR → 0.82V
PP3V3_AWAKE → 3.36V
PPVDDCPUSRAM_AWAKE → 0.8V
PP0V9_SLPDDR → 0.90V
P1V1_SLPDDR_SOCFET_EN → 1.80V
PP1V1_SLPDDR → 1.10
SOC_XTAL24M_IN → 0.54V
PP1V2_AWAKE → 1.19V
PPVDDCPU_AWAKE → 0.75V
PMU_COLD_RESET_L → 1.79V
PMU_SYS_ALIVE → 1.80V
PP3V3_G3H → 3.36V
P3V3MAIN_PGOOD → 3.24V

 

[2informaticos]

"L9580 to Ground 4.7OHMs
Can't find any short."
How not?
4.7 ohm is almost pure short; correct value is aprox 0.425 in diode mode.

Sorry, but ADIOS data...

 

[ronaldo]

Ok. It may sound stupid or I'm being stupid, but I was measuring short to ground in Ohms by setting my multimeter to OHMS and black probe to ground and red probe on the L9580 - P2V5_SW1_TPS62180_SSD0.
Before it was showing 4.7ohms.
Now it keeps increasing till reach 20.2K.

In diode mode
L9580 - 0.380
L9581 - 0.380

 

[2informaticos]

Then no short at all.
0.380 can be good.
You can't expect exact the same reading on different boards; even are the same model.

Is the battery charging?
Try DFU with (good) battery connected.

 

[ronaldo]

Yes, battery is charging.
Ok I will try DFU with a good working battery tomorrow.

 

[ronaldo]

I just tried DFU revive with another good battery and same results.

 

[ronaldo]

820-01700 - T2 pulsing

youtube.com

On this video, you can see T2 chip pulsing.

I don't know if it was pulsing before, but I just realized now that these lines are pulsing every 2 sec.
PP1V8_SLPS2R → Pulsing
PP1V8_AWAKE → Pulsing
PP1V1_SLPS2R → Pulsing
PP0V8_SLPS2R → Pulsing
PP0V82_SLPDDR → Pulsing
PP3V3_AWAKE → Pulsing
PPVDDCPUSRAM_AWAKE → Pulsing
PP0V9_SLPDDR → Pulsing
P1V1_SLPDDR_SOCFET_EN → Pulsing
PP1V1_SLPDDR → Pulsing
PP1V2_AWAKE → Pulsing
PPVDDCPU_AWAKE → Pulsing

L9580 - P2V5_SW1_TPS62180_SSD0 - 0V

 

[2informaticos]

PPBUS_G3H and 3V3_G3H_RTC also pulsing?

 

[ronaldo]

Not pulsing.
PPBUS_G3H - 12.30V
3V3_G3H_RTC - 3.38V

 

[2informaticos]

T2 voltages have been stable, if it was detected in DFU mode.
What happens in the meantime?

Using original 96/140W charger for sure?
Check diode mode to ground on all big coils; including SSD related.

 

[ronaldo]

The charger I'M using is an original 96W.
All the coils are good in diode mode, including SSD.
Do you think that there is any chance that U7800 - CALPE-PMU is faulty?

 

[2informaticos]

Diode mode readings on the small coils arround U7800 match good board?

You may have problems with T2, or PMU.
U7800 LDOs are stable?