820-00840 dead.

[yair37]

the board was work on an off sometime was turn on and sometime not.
Board without battery, unplugged all connectors takes from charger:
20.33V
0.052A

Power rails:
PPBUS_G3H - 13.7V
PPDCIN_G3H - 20.35V
PP5V_S5 - 0V
PP3V3_G3H - 3.426V
PP3V3_S5 - 0V
PP1V8_S3 - 0V
pp3v3_sus - 0.00v
pp3v3_s5 - 0.00v
Buf_smc_reset_l - 3.424v
smc_pm_g2_en - 3.420v

U7890:

1 ssd_pwr_req - 0v
2 pmic_en_p3v3s5 - 0v
4 pm_en_pvxs5 - 0v
6 pp3v3_g3h - 3,42v

U7800 was burnd when i was do checking this rails but i was replaced and now i get this voltage
PPBUS_PMIC -13v
PP3V3_LDO3V - 3.3v
PMIC_SHUTDOWN_L 3.2v

 

[2informaticos]

U7800 was burnt, or got burnt when you made some short measuring on the board?

1V25_VREF and 3V1_RTC present?

 

[yair37]

was burnt, new is o.k
1V25_VREF 1.2V
3V1_RTC 3.1V

 

[2informaticos]

Check for moved components, reflow U7800; be sure to get good solders.
The heat could affected other chips, is other option.

 

[yair37]

So it just U7800 area problem..?

 

[2informaticos]

Maybe CPU, or SMC; the heat could affected them...

 

[yair37]

i was just sew a little bit corrosion under Q3100 clean and replaced but the same...charger without battery 20V 0.23A can it be the from there?

 

[2informaticos]

If you don't even get 3V3_S5, 0.23A is too high.
20V means the USB-C area is good.

You may have a problem around U7000/800.