820-3115, no power

2informaticos

Administrator
Staff member
Sorry, PM_SLP_S4_L should go high at that moment.
Check if PM_PWRBTN_L drops.

What was the reason to change SMC?
It must be changed in base of some measurments...
 

yobad

Member
Yes, PM_PWRBTN_L drops when I short SMC_ONOFF_L
and PM_SLP_S4_L always 0v

I replaced SMC just in case.
But no reason,
 

2informaticos

Administrator
Staff member
Check the 4 RTC signals, page 16.
Also post PM_BATLOW_L, PCH_DSWVRMEN, PM_DSW_PWRGD, PM_RSMRST_L.
Do you get both 3V3_S5/SUS?
 

yobad

Member
PM_BATLOW_L 3.3v
PCH_DSWVRMEN 3.3v
PM_DSW_PWRGD, 3.3v
PM_RSMRST_L 3.3v

3V3_S5 3.3v
PP3V3_SUS 3.3v
Check the 4 RTC signals, page 16, I found only
SYSCLK_CLK32K_RTC it is 0v could you give me the 3 other net names?

this values after trying SMC bypass mode and it consume 0.07a

if I start the normal mode it will consume only 0.02a and all these signals are 0, PM_BATLOW_L, PCH_DSWVRMEN, PM_DSW_PWRGD, PM_RSMRST_L.
 

2informaticos

Administrator
Staff member
How many signals do you see on PCH's RTC block at page 16???
32KHz clock was the last expected; beeing oscillation, not DC value.
 

yobad

Member
Okay, but I think I was wrong to identify the page, page 16 is CPU Decoupling-I.
i don't think this the one that you mean ?!
 

2informaticos

Administrator
Staff member
In my schematic appears like "PCH SATA/PCIe/CLK/LPC/SPI" page; sheet 16 of 86.
Look at U1800 (1 of 10), RTC block...
 

yobad

Member
also PP1V05_S0 0.4v, line resistance 11.5ohms, and on a good board 14.9ohms

could be a bad CPU?
 
Last edited:

2informaticos

Administrator
Staff member
Readings could differ from board to board, do not expect exact same value.
Also CPU type is important; i7 will give lower values than i5, which will be lower than i3.

RTC signals look good.
So, can you see 3.3-0-3.3V drop pulse at PM_PWRBTN_L when trigger SMC_ONOFF_L?
In such case (at same moment) should catch a high pulse at PM_SLP_S4/3_L signals.
Trigger SMC_ONOFF_L several times and maintain voltmeter connected at these signals.
 
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