820-00850 that is stuck on 5V at 0.294A

[ronaldopdias]

Hi everyone. I need a help with this Mac, please.

The logic board shows no signs of life , is clean with no liquid damage, and is stuck at 5V and 0.294A on all ports.
DFU attempted, but it stalled halfway through the system installation.

Mac turns on with a working battery, but doesn't charge it.
With a Working battery the voltages are 20V at 0.0300a

PPBUS_G3H - 12.28V
XB, XA, TA, TB are all measuring same voltage.

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

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

U7000 replaced and still same.
UB090 and U2890 replaced from a donor board and still same.

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

R7020 not getting any voltage.
PPDCIN_G3H is missing when the charger switches to 20V. Without the battery it gets 5V on the PPDCIN_G3H.

all ports have the same behaviour, flipping the cable too.

D6950 replaced and same.
Without battery.
SMBUS_3V3_BATT_SCL - 3.36V
SMBUS_3V3_BATT_SDA - 3.36V

With the battery it goes to 0V

[mon2]

Select the USB port linked to U3200.

Power up with the external power adapter. Measure the voltage to ground of PP20V_USBC_XB_VBUS_F @ Q3200 dual mosfet. Does this same voltage pass onto PPDCIN_G3H?

When the adapter is in 20v, same power path voltages?

What is the voltage to ground of the following power pins on U7000?

CHGR_VDDA ; measure @ C7075 (pin 1)
CHGR_VDDP ; measure @ C7077 (pin 1)

[ronaldopdias]

The Q3200 gets 20V on pin 7 - PP20V_USBC_XB_VBUS_F.
20V is not present on the PPDCIN_G3H pin 8 when the charges is 20V.

[mon2]

Review the G1 and G2 voltages to ground on Q3200 under the same conditions.

[ronaldopdias]

G1 - 0V
G2 - 20V

[mon2]

Remove all power. Measure the resistance between S2 / G2. Also S1 / G1.

[ronaldopdias]

No resistence.
S2 / G2 - OL
S1 / G1 - OL

Diode measurement.
Q3200 pins:
1 - 0.660
2 - 0.650
4 - 0.650
5 - 0.192
8 - 0.566

[mon2]

Test the resistance of:

G2 / D2 (pin 3)
S2 / D2 (pin 3)

G1 / D2 (pin 3)
S1 / D2 (pin 3)

[ronaldopdias]

All those options are OL
D2 is pin 2, but they are connected together pin 2 and 3.

[ronaldopdias]

CHGR_VDDA ; measure @ C7075 (pin 1) 0.465
CHGR_VDDP ; measure @ C7077 (pin 1) 0.465

[mon2]

What voltage do you see with the adapter on:

CHGR_VDDA ; measure @ C7075 (pin 1)
CHGR_VDDP ; measure @ C7077 (pin 1)


What are the resistance to ground of each of the following?

PP2V7_NAND_SSD0
PP0V9_SSD0
PP1V8_SSD0

PP3V3_G3S
PP5V_G3S

[ronaldopdias]

CHGR_VDDA ; measure @ C7075 (pin 1) 5.10V
CHGR_VDDP ; measure @ C7077 (pin 1) 5.10V

PP2V7_NAND_SSD0 2.52V
PP0V9_SSD0 0.90V
PP1V8_SSD0 1.80

PP3V3_G3S 3.38V
PP5V_G3S 5.14V

[mon2]

Review this flowchat for the CD3215. Appears that HV_GATE1 is not working.

https://logi.wiki/index.php/CD3215_Bootup_Sequence

[ronaldopdias]

Do you know if CD3215C00Z is compatible with CD3215C00?

[mon2]

Someone on Rossmann forum did this and believe it worked.

[ronaldopdias]

U3200 replaced and fixed the problem
Battery is now charging and working fine.
Thanks for your help.

[mon2]

Well done!