820 2936 dead

[EJS]

PPBUS G3 12.59v
PP3V42 3.47v
PP5V S5 5.02v
PP5V S3 0v
PP3V3 S3 0v
PM SLP S4 L 0v

 

[2informaticos]

Any pulse at least at PM_SLP_S4_L?
Trigger SMC_ONOFF_L and check again.
Do you get 3V3_S5 and 3V3_SUS?
Also check SMC_ADAPTER_EN and PM_BATLOW_L.

 

[EJS]

SMC_ADAPTER_EN 3.45v
PM_BATLOW_L 0v
3V3_S5 3.32v
3v3 SUS 0v
No pulse on PM_SLP_S4_L, at least none that my multi meter could pick up. Toggled SMC ON/OFF, no change.

 

[2informaticos]

"PM_BATLOW_L 0v"
Original Apple 60/85W charger tried for sure?

 

[EJS]

Yes, 0v PM BATLOW L measurement taken from pin 2 @ Q5040. I am using an OEM Apple 85w Magsafe 1

 

[2informaticos]

PCH will not start power on sequence untill PM_BATLOW_L goes high.
Any history available?
You may need to replace SMC, or reflow it at least.
Check S5_PWRGD signal, as PM_DSW_PWRGD and PCH_DSWVRMEN too.

 

[EJS]

No real history machine just stopped powering on as far as I know. The board looks like its in good shap, no LD.

S5_PWRGD 0v
PM_DSW_PWRGD 3.470v
PCH_DSWVRMEN 3.201v

 

[2informaticos]

"S5_PWRGD 0v"
You've mentioned 3V3_S5 is OK.
Post all voltages of U7941.

 

[EJS]

Pin 1 3.47v
Pin 2 3.47v
Pin 3 3.45v
Pin 4 0v
Pin 5 0v
Pin 6 3.32v
Pin 7 0v
Pin 8 3.45v

 

[2informaticos]

"S5_PWRGD 0v
-------------
Pin 8 3.45v"
Is the same line; check again.
Maybe broken trace...

 

[EJS]

I definitely have 0v 9n pin 2 @ R2584

 

[2informaticos]

Mmmhhh, what is the relation between U7941 and R2584???
Pay atention, I asked about S5_PWRGD, not XDP_PCH_S5_PWRGD...

 

[EJS]

Sorry 2info, I did not notice that, when I searched S5 PWRGD on boardveiwer it highlighted that line as well. So I have 3.45v on S5_PWRGD.

 

[2informaticos]

Check if all 4 RTC signals have high level (page 16).
32KHz output from U2800 should be present too.

 

[EJS]

SYSCLK CLK32K RTC .383v
RTC RESET L 3.31v
PHC SRTCRST L 3.31v
PCH INTRUDER L 3.03v
PCH INTVRMEN L 3.21v

 

[2informaticos]

Check SMC_BATLOW_L.
If high, then should be PCH issue, pulling down PM_BATLOW_L.
In such case use good flux and heat PCH.
You may have luck and is only some crap under...

 

[EJS]

SMC_BATLOW_L is 0v

 

[2informaticos]

If you are sure about original Apple 60/85W charger, then could be SMC issue.
You can try to reflow it; change it if no result...

 

[EJS]

Im positive this is a 100% working OEM Apple charger, I bought it straight from the Apple store. I replaced the SMC, no change.

 

[2informaticos]

Try to start in SMC bypass mode, just in case.
Also try to start with battery and charger, both connected?
Not normal, but is possible that PCH blocks the SMC and this keeps SMC_BATLOW_L low.

Can you confirm with o-scope 32KHz square wave output from U2800?
Frequency meter is also good enough.