820-00165

[No-Clean]

Clean board.

Already reballed SMC as it looked like it had some corrosion but it was pretty clean.

PPBUS_G3H -> 8,56V
PPVRTC_G3H -> 3,3V
ALL_SYS_PWRGD -> 0V
PP5V_S5 -> 5V
PP3V3_S5 -> 3,3V
PP3V3_SUS -> 3,3V

When I Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (at same time), But sometimes PM_PWRBTN_L will stay at 1.4V, most of the times comes back to 3.4V.

I don't get a pulse on PM_SLP_S4_L when I repeat the SMC_ONOFF_L trigger and it is 0V, if I try multiple times I may get a random pulse.

SMC bypass same thing.

 

[2informaticos]

PM_PWRBTN_L should drop to 0V, when SMC controls it.
You may have problems with this SMC; try changing it.

Also check PM_RSMRST_L level.

 

[No-Clean]

New SMC:

When I Trigger SMC_ONOFF_L and check for drop pulse at PM_PWRBTN_L (at same time) I do get a drop from 3.4V to 0V
When I Trigger SMC_ONOFF_L and check for drop pulse at PM_SLP_S4_L (at same time) I do get a very fast pulse from 0V to 2.7V hard to catch with multymeter
When I Trigger SMC_ONOFF_L and check for drop pulse at PM_RSMRST_L (at same time) I do get a drop from 3.3V to 0V

Also seems like most other rails pulse too.

 

[2informaticos]

PM_RSMRST_L must stay always high.
Don't you have steady 3V3_S5/SUS?

"check for drop pulse at PM_SLP_S4_L"
Never!
You should catch the pulse (low to high), as you mentioned above.

All big coils pulsing?
Test SMC bypass.

 

[No-Clean]

Ok lets start over:
3V3_S5/SUS Both steady no pulse
PM_RSMRST_L 3.3V
SMC Bypass same thing

Big coils pulse ONLY when I trigger SMC_ONOFF

 

[2informaticos]

"Big coils pulse"
All of them, including CPU core???

What about PLT_RESET_L?
PM_RSMRST_L still dropping?

 

[No-Clean]

Coils pulsing:
PP5V_S4RS3
PPDDR_S3_REG_R
PP1V05_S0_REG_R

No pulse:
PPVCC_S0_CPU_PH2
CPU Code no pulse

And remember this are steady:
PPBUS_G3H -> 8,56V
PPVRTC_G3H -> 3,3V
ALL_SYS_PWRGD -> 0V
PP5V_S5 -> 5V
PP3V3_S5 -> 3,3V
PP3V3_SUS -> 3,3V

 

[2informaticos]

Inspect U1950 for corrosion.

 

[No-Clean]

U1950 clean, did a reball/reflow just in case, same thing
PLT_RESET_L 0V steady
PM_RSMRST_ 3.2V steady

 

[2informaticos]

ALL_SYSTEM_PWRGD should pulse at same time with L7630.
If not, remove Q8150 and test again.

 

[No-Clean]

Both ALL_SYSTEM_PWRGD and L7630 pulse but only when I trigger SMC_ONOFF

 

[2informaticos]

L7310/20 still not pulsing?

Just for test, tie together pins 5 & 6 of U1950.

 

[No-Clean]

Removing Q8150 same thing
Tied together pins 5 & 6 of U1950 same thing and no pulse either on L7310/20.
No pulse at L7310/20 before or after the above changes

 

[2informaticos]

Just in case, try known good BIOS.

 

[No-Clean]

Clean good BIOS, same exact thing.

 

[2informaticos]

Check U7200 basic power and signals: pins 17, 16, 1.
Also check all SPI Bus Series Termination resistors and their traces.
Inspect J6100 for corrosion.

 

[No-Clean]

U7200 had a tiny bit of corrosion under it, had to replace it 2 times and it worked!

Muchas gracias!