820-00293 - No power - Stuck on 5v 0.06A

[ronaldopdias]

Board Model: 820-00923
Issue: Board takes 5V @ 0.694A on all ports. No signs liquid.

Customer stated: Died during an update whilst battery was at 10%. Tried plugging in but it died.

Board takes 5V at 0.06A on all USB-C ports..
Board is clean with no visible corrosion or liquid damage.

PP1V8_UPC_TA_LDOA - 1.8V
PP3V3_UPC_TA_LDO - 3.32V
PP1V8_UPC_TA_LDOD - 1.8V
PP1V1_UPC_TA_LDO_BMC - 0V

PP1V8_UPC_TB_LDOA - 1.8V
PP1V1_UPC_TB_LDO_BMC - 0V
PP1V8_UPC_TB_LDOD - 1.8V
PP3V3_UPC_TB_LDO - 3.28V

PP3V3_UPC_XB_LDO - 3.1V
PP1V8_UPC_XB_LDOA - 1.8V
PP1V8_UPC_XB_LDOD - 3V
PP1V1_UPC_XB_LDO_BMC - 0V

PP3V3_UPC_XA_LDO - 3.3V
PP1V8_UPC_XA_LDOA - 1.8V
PP1V8_UPC_XA_LDOD - 1.8V
PP1V1_UPC_XA_LDO_BMC - 0V

PPBUS_G3H - 0V
PPDCIN_G3H - 5.16V

Battery connected doesn't make any difference.
USB-C current does not change regardless of port used.

Parts Replaced:

• U7000
• U7800
• CD3215 – replaced all 4 with known-good chips from a donor board.
• U2890/UB090 (TBT ROM) – replaced from a good known board.
• SMC chip – replaced with a good one from a donor.

Appreciate any help, please.

[mon2]

PPBUS_G3H - 0V

Remove all power. Meter in resistance mode. What is the exact resistance to ground of PPBUS_G3H?

[mon2]

None of the _BMC rails are at 1V1 while in use of that port?

PP1V8_UPC_XB_LDOD - 3V

This does not look correct.

[ronaldopdias]

PPBUS_G3H - 0.459 in diode mode.

[mon2]

U7000 is a suspect since 0v output and part was replaced.

Consuming 60mA or 600mA?

[ronaldopdias]

PP1V8_UPC_XB_LDOD was 3V because I kicked out C3205. After replacing it, it now gets 1.8V.
Also, I found a short on PPVIN_G3H_P3V3G3H leading to faulty cap C7081. Cap replaced and same results.
Stuck on 5v @ 0.04A

[ronaldopdias]

U7000 replaced and still the same.
40mA