820-3115 no ppdcin_G3h

[Yoel Ren]

this came in with various side liquid damaged, i have replaced u7000, q7030 q7035, q7080, but still no ppdcin, even though there's no short..
using fake charger no green light too..

 

[2informaticos]

Do you get 3V42_G3H with fake charger, or lab PSU?

 

[Yoel Ren]

with fake charger, i get 12.6 at ppdcin_g3h

 

[Yoel Ren]

wait , it become 0.8v with fake charger at ppdcin_g3h

 

[2informaticos]

Lab PSU, or fake charger should always deliver =PPDCIN_S5_CHGR.
Did you mean PPBUS_G3H, instead of PPDCIN_G3H?

 

[Yoel Ren]

r6995 is bad, replaced, now I have pp16v5 at ppdcin, pp3v42 3.42v
smc_bc_acok 3.4v
adapter_sense is 3.4v up to pin 5 of charging port
sometimes i have green light, and then i replug the port, and its gone, and ppdcin_g3h is back at 1.6v,..

 

[2informaticos]

Try another DCIN board.
Do you get stable PPBUS_G3H?

 

[Yoel Ren]

when I have full ppdcin, ppbus is at 12.26v, yes i did suspect smc, i will give it a light reflow
dcin board is known good

 

[2informaticos]

Incorrect PPBUS_G3H voltage.
Check first SMC_RESET_L.
If good, check voltage and diode mode to ground at SCL/SDA lines of battery bus.

 

[Yoel Ren]

but most of time, I either have 0v or low ppdcin..
does smc_reset_l cause low ppdcin ? there's no short on smc_reset_l but i cannot measure thevoltage because i dont even have ppdcin

 

[Yoel Ren]

i actually have a 30 ohm short on pp3v3_s0, but i intend not to bother with it until I have stable green light

 

[Yoel Ren]

yeah this board is massacred by another technician before..

 

[2informaticos]

Thonk if worth to waste time on it then.
Do you get PPBUS_G3H alwaysif power it with lab PSU, or fake charger?
If yes, this denotes an input leakage issue.