820-3536 - won't turn on

[Palhano]

Board without history. There are no oxidations.

RTC_RESET_L - 3.26V
PCH_INTRUDER_L - 3.3v (It was 1.65v, I changed it to 100k)
PCH_INTVRMEN - 2.5v
PCH_SRTCRST_L - 3.26V

PPBUS_G3H - 12.56v
PP3V42_G3H - 3.4v
PPVRTC_G3H - 3,3V
PP5V_S5 - 5v
PP3V3_S5 - 3.3V
PP3V3_SUS - 3.3V

SMC_ONOFF_L - 3,37v
SMC_ADAPTER_EN - 3.3V
SMC_PM_G2_EN - 3.4V
*PM_BATLOW_L - 0
PM_PWRBTN_L - 3.4V
PM_RSMRST_L - 3V
*PLT_RESET_L - 0
*ALL_SYS_PWRGD - 0

PM_BATLOW_L is generated by SMC (correct?), I tried reballing but it didn't work.

 

[2informaticos]

Did you try with original 60/85W Magsafe 2 charger?
Also try with both charger and battery connected.

 

[Palhano]

Yes, always with original MagSafe 2 85w.
Tried with battery, dead too!

Today when I tested again, the cooler rotated for a few seconds and stopped. Now he's dead again.

 

[2informaticos]

Check R1410 if good.

 

[Palhano]

All ok with R1410. But PM_BATLOW_L started to measure 3.3v. But still with PLT_RESET_L 0v.

 

[2informaticos]

Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (at same time).

 

[Palhano]

PM_PWRBTN_L drops to 0.3v, when I trigger smc_onoff

 

[2informaticos]

Check (at same time) for pulse at PM_SLP_S4_L.

 

[Palhano]

No pulse in PM_SLP_S4_L

 

[2informaticos]

Looks like PCH problem, which also explains the initial issue with PCH_INTRUDER_L signal.

 

[Palhano]

I suspected! thank you so much for your help as always!