820-00840 No S5

My reference: REF1144

Board History: Some liquid damage, would not power on at all.
Replaced: U7000, U7650, C7689, C7651.
USB meter goes to 20v.
When I first plug in the charger, I see it jumps up to about 3v on C7651 during the first few seconds of being plugged in, but it drops off.

Did you test the board alone on the desk?

Check diode mode to ground on all power rails and compare with good board.
Also check basic voltages on U7650; pins 23, 22, 12, 13, 29, 21.
Be sure all resistors and traces from feedback networks are good.

Any pulse at L7690?

2informaticos said:

Any pulse at L7690?

Click to expand...

Nothing at L7690. I do not have a known good board.

All my measurements I have been providing has been with the board out on the desk.

U7650 Pins:
23: 13.04v
22: 3.29v
12: 0v
13: 0v
29: 0v
21: 0v

All power rails before leading up to S5 seem to be present. There is damage in the backlight areas but this is for S0, would the backlight compomnents affect this?

No pulse at all at pin 12?
SMC_PM_G2_EN comes high (stable)?

Check U7800 (7 OF 10) output voltages; its 3V1_RTC also.

2informaticos said:

SMC_PM_G2_EN

Click to expand...

Yes, 3.4v and stable.

U7800, I am not confident which U7800 voltages I am supposed to check:
PMIC_SYSPWROK: 0v
PMIC_PCH_PWROK: 0v
PMIC_ALLSYSPGD: 0v
PMIC_RSMRST_L: 0v
PMIC_INT_L: 3.3v
PM_PGOOD_P1V8: 0v
PM_SLP_S5_L: 0
PP3V1_RTC: 3.089v
PMIC_VCCST_PGD: 0v
PPBUS_PMIC: 13.04v
PM_PCH_PWROK: 0v
PM_EN_PVCCPCH: 0v
PMIC_PGB: 0v
PMIC_PGD: 0v

I specified U7800 (7 OF 10) section!
You've missed all of them...