820-4924 just s5 rails

[rlowe215]

Im working on a liquid damage. Corrosion around U1950. Replaced components in the area.

Some measurements so far.

PPBUS_G3H 12.59v

PPBUS_S5_HS_COMPUTING 12.6

PPBUS_S5_HS_OTHER5V 12.58

PPBUS_S5_HS_OTHER3V3 12.6

PP5V_S5 5.01

PP5V_S4 0v

PP3V3_S5 3.3v

PP3V3_S4 0v

PM_SLP_S5_L 0v

PM_SLP_SUS_L 0v
SMC_ADAPTER_EN 0v

L7560 3.3v

S5_PWRGD 3.3v
PPVRTC_G3H 2.97v
SMC_RESET_L 3.37v
SMC_PM_G2_EN 3.39
PP3V3_SUS 0v
SMC_DELAYED_PWRGD 0v 0.650v
SMC_THRMTRIP 0v
SMC_BC_ACOK 0v

Any ideas?

 

[rlowe215]

SMC_ADAPTER_EN 0v and seems to be shorted to ground 3.2 ohm.
Removed R5185 still shorted.
Replaced SMC but measured SMC_ADAPTER_EN without SMC in place and still short.
Anything else then PCH that can short this line ?

 

[2informaticos]

Check for corrosion at R5185.
Not probably, but is the only thing you can check.
Because the other suspect is PCH (CPU).

I hope you measured resistance to ground without power applied...

 

[rlowe215]

never power applied when measure resistance =) and no corrosion at r5185 and shorted even with r5185 removed as said

 

[2informaticos]

Put good flux and heat PCH.
You may have luck to be only crap under it.
Is the last option you have...