820-00840 no start

[rlowe215]

New to this boards. Some waterdamage in trackpad connector area and burned connector. Replaced shorted connector and worked. After connecting keyboard board died again, guess keyboard waterdamaged too.

Board now have 20V and draws 0.15A

ppbus_g3h 13.1
3V3_G3H 3.4
pp3v3_s4 3.3
pp5v_s4 5.12
pp3v3_s0 0v
PP5V_S0 5.12v

SMC_PM_G2_EN 1.8v
ALL_SYS_PWRGD 3.2v
PM_PCH_SYS_PWROK 0.24v
CPU_VCCST_PWRGD 1v

 

[2informaticos]

"pp3v3_s0 v"
Check diode mode there.
Also check U8220 input and enable.

Test the board alone, nothing connected, apart of charger.

 

[rlowe215]

sorry seems to been something wrong with first measurement. Now pp3v3_s0 there 3.3v. Have the bord on desk with only charger connected on all measurements

 

[2informaticos]

Do you get VCORE (L7210/20)?
If yes, check USB activity.

 

[rlowe215]

Vcore 0V

 

[rlowe215]

checked with thermal cam and U7210 heated up, replaced it and now back to working and booting. But how do keyboard short out U7210?