820-3115 no power

[2informaticos]

Secondary voltages should appear even without SPI chip soldered; less the CPU ones.
So, PM_SLP_S4_L should pulse at least; check that.

Post again all the signals mentioned in the previous posts...

 

[Kyle93]

PM_SLP_S4_L does not pulse at all

PM_SLP_SUS_L 0V

RTC_RESET_L 3.482V

PCH_SRTCRST_L 3.481V

PCH_INTRUDER_L 3.195V

PCH_INTVRMEN_L 0V

SMC_ONOFF_L 3.487V

 

[Kyle93]

Noticed there was a short on PP5V_S5.

Soldered SPI chip back on for testing. Replaced U7801 and U7200 and now PM_SLP_S4_L is pulsing at 3.3V with a quarter fan spin every few seconds.

Do I just need new ME region now? If so can someone provide?

 

[2informaticos]

"PM_SLP_SUS_L 0V"
PCH doesn't want to set it high.

And here is the reason.
"PCH_INTVRMEN_L 0V"
This signal should be high now, if machine tries to start.

"PM_SLP_S4_L is pulsing at 3.3V"
Check if all voltages controlled by it pulse too.
Do the same for PM_SLP_S3_L.
Also look if ALL_SYS_PWRGD pulses.

 

[Kyle93]

suddenly lost my old voltages since I last checked this board. I have nothing for PM_SLP_S4_L now and no more quarter fan spin.

pp3v42 3.42 V but no green light PPBUS_G3H only 1.060V now

what to check next in this case?

 

[Kyle93]

replaced q7085 now back to quarter fan spin

all voltages for PM_SLP_S4_L are pulsing along with PM_SLP_S3_L and ALL_SYS_PWRGD

 

[2informaticos]

Do you note pulsing CPU coils too?

 

[Kyle93]

cpu coils pulsing at 0.971V

 

[2informaticos]

25MHz oscillation tries to appear at pin9/U2600?

 

[Kyle93]

I have the fluke 15b+ multimeter and I do not believe it supports MHz oscillation. Is there another way to check?

 

[2informaticos]

Try this as is; if works, then you may change the serial...
https://drive.google.com/open?id=1RFRVA7vkn2gGPN7hpuXlNwLCIiMrNx5G

 

[Kyle93]

Just tried it but nothing has changed. Anything else I can try?

 

[2informaticos]

Check if all the voltages from page 72 try to appear.
Also check all SPI termination resistors and traces around U6100.