820-00850 Stuck on 5V 0.294a

[ronaldo]

This LB has no signs of life.
Stuck on 5V 0.294a on all ports.
No liquid, very clean inside.
Tried DFU and it gets stuck half way on installing system.
SLPS2R and AWAKE voltages are present.
No short on the board and all coils measurements is good.
S5 voltages are missing.
PPBUS_G3H - 12.28V
On U3200 - UPC_XB_GATE2 it's getting 10.78V. I think it should be 5v then 20V.
The T2 glows under thermal camera.

Any help would be great, please.

 

[ronaldo]

PP20V_USBC_XB_VBUS - 5V
PP3V3_UPC_XB_LDO - 3V
PP1V8_UPC_XB_LDOA - 1.8V
PP1V8_UPC_XB_LDOD -1.8V
PP1V1_UPC_XB_LDO_BMC - 1.11V

 

[2informaticos]

You've posted only "XB" channel readings.

MOSFET's Gate doesn't work as you think!

Do you get SSD and G3S voltages?
Tested the board with charged battery?

 

[ronaldo]

With working battery it goes to 20V 0.02A.

PP2V7_NAND_SSD0 - 0V
PP0V9_SSD0 - 0V
PP1V8_SSD0 - 0V

PP3V3_G3S - 0V
PP5V_G3S - 0V
PP5V_G3S - 0V
PMU_ONOFF_L - 3.38V

PP20V_USBC_XB_VBUS - 20V
PP3V3_UPC_XB_LDO - 3.3V
PP1V8_UPC_XB_LDOA - 1.8V
PP1V8_UPC_XB_LDOD -1.8V
PP1V1_UPC_XB_LDO_BMC - 1.11V

PP20V_USBC_XA_VBUS - 20V
PP3V3_UPC_XA_LDO - 3.35V
PP1V8_UPC_XA_LDOA - 1.8V
PP1V8_UPC_XA_LDOD - 1.8V
PP1V1_UPC_XA_LDO_BMC - 1.11V

PP20V_USBC_TA_VBUS - 20V
PP3V3_UPC_TA_LDO - 3.35V
PP1V8_UPC_TA_LDOA - 1.81V
PP1V8_UPC_TA_LDOD -1.8V
PP1V1_UPC_TA_LDO_BMC - 1.11V

PP20V_USBC_TB_VBUS - 20V
PP3V3_UPC_TB_LDO - 3.35V
PP1V8_UPC_TB_LDOA - 1.81V
PP1V8_UPC_TB_LDOD -1.8V
PP1V1_UPC_TB_LDO_BMC - 1.11V

 

[2informaticos]

Does that battery hold some charge?
Test if board turns on with it.

 

[ronaldo]

The Mac battery is dead. But the other one I'm using holds charge.
It turns on with a charged battery, but does not charge.

The first time I connect the battery and charger it stays on 5V. Then I disconnect the charger and plug it again then it goes to 20V and stays there.

 

[2informaticos]

Then the problem is located on USB-C, or U7000 areas.

Try reflashing TBT ROMs.

 

[ronaldo]

U7000 replaced and still same.
UB090 and U2890 replaced from a donor board and still same.
I couldn't find the ROM files to flash into the ICs.

 

[ronaldo]

On R7062 - CHGR_CSO_R_N and R7061 - CHGR_CSO_R_P it should be 0.467 in diode mode, but instead it's measuring 0.372.
Is this an issue?

 

[ronaldo]

PPDCIN_G3H is missing when the charger switches to 20V.
Q7030 all ok, but none of the pins has power.

 

[2informaticos]

Post U7000 basic voltages: P_IN, AUX_DET, SMC_RST_IN, VDDA/P, A/BMON.

 

[ronaldo]

On battery.
P_IN - 0V
AUX_DET - 0V
SMC_RST_IN - 0V
VDDA/P - 5.11V
A/BMON - 0V

 

[ronaldo]

After disconnecting the battery and connecting it for the first time. The charger stays on 5v.
P_IN - 5.15V
AUX_DET - 1.28V
SMC_RST_IN - 0V
VDDA/P - 5.11V
A/BMON - 0V

Leaving the battery in and unplug and plug the charger then it goes to 20 and the voltages are:
P_IN - 0V
AUX_DET - 0V
SMC_RST_IN - 0V
VDDA/P - 5.11V
A/BMON - 0V

 

[2informaticos]

When charger is plugged in (no matters battery present, or not) R7020 must get voltage.

Check if all ports have the same behavior.
Test flipping the cable too.

 

[ronaldo]

Same behaviour on all ports. Both sides.
R7020 just get voltage without battery and charger stuck on 5V.

 

[2informaticos]

Still get correct LDOs on CD3215 chips, when no voltage at R7020?

Check resistance (ohm scale) over C7020/23.

 

[ronaldo]

Same voltages on the LDOs on all CD3215 chips, when no voltage on R7020.

resistance (ohm scale) over
C7020 - 50Kohms
C7023 - 50Kohms

 

[2informaticos]

Are you sure about these readings?
You should get 2-3 ohm there...

 

[ronaldo]

My bad, I was checking the resistance to ground.
Over then is 4.5ohms on both.

 

[ronaldo]

I replaced both and it now has
C7020 - 3.5ohms
C7023 - 3.1ohms
It hasn't change the charging issue.