A1502 820-3476, water damage, green light, PP3V3_S0 = 2v

guzq

New member
Hey Guys,

Working on 820-3476 with severe water damage and corrosion. Replaced all bad components, using original Apple MagSafe 60w green light but no fan spin.

Here my measures:

PPBUS_G3H : 12.57v
PP3V42_G3H : 3.42v
PPVRTC_G3H : 3.3v
SMC_ADAPTER_EN : 3.398v
PP3V3_SUS : 3.3v
PP3V3_S5 : 3.3v
PP3V3_S4 : 0.452v
PP3V3_S3 : 0.384v
PP3V3_S0 : 2v (not normal)
PP5V_S5 : 5v
PP5V_S4 : 0v
PP5V_S0 : 0v

ALL_SYS_PWRGD : 0v

PCH_SUSACK_L : 3.3v
PM_RSMRST_L : 3.3v
PM_BATLOW_L : 3.3v
PM_DSW_PWRGD : 3.42v
PM_SYSRST_L : 2v (not normal)

PM_PCH_SYS_PWROK : 0v
PM_PCH_PWROK : 0v
PLT_RESET_L : 0v
PM_SLP_S5_L : 0v
S4_PWR_EN : 0v

Replaced U8030, PP3v3_S0 still 2v
Missing S4 rails also.
 

2informaticos

Administrator
Staff member
Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L.
If yes, then check for pulse at all PM_SLP_Sx_L signals, at same time.

Did you try SMC bypass mode?
 

2informaticos

Administrator
Staff member
Looks like you have PCH issue.

"How do i try this ?!"
Press power button, connect charger and maintain pressing 5-10s.
Remove battery first.
 

guzq

New member
Cleaning area around CPU/PCH, now PM_SLP_S5_L pulsing from 2.472v to 0v for less than a second.

PCH issue ???
 

2informaticos

Administrator
Staff member
"now PM_SLP_S5_L pulsing from 2.472v to 0v"
When it is high, machine must exit from S5 state, going to S3.
Do you get pulse on other PM_SLP_Sx_L signal at same time?
 
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