820-2915 missing s3 rails

[Chuck60]

So I received a board that’s missing pm_slp_s4_L looks like someone had removed the bios. I checked the vias and
They seem good. I checked the spi bios Bi-directional Via as well. The hold signal spirom_use_mlb 0v.
Pm_Pch_pwrok=3.42v

U2800
Ppvrtc_g3h =3.27v
Pp3v3_s5 = 3.3v
Pp3v42_g3h = 3.42v
Sysclk_clk25m_x2_r = 0v
sysclk_clk32k_rtc =0v

u2800 pin 12 has (32.6khz frequency measured with oscilloscope)

U4900
pp3v3_s5_avref_smc = 3.42v
Smc_onoff_l =3.42v
Smc_reset_l = 3.42v

u6100
Pin 1 = 0
Pin 2 = 3.3v slp_mlb_miso
Pin 3 = 3.3v soi_wp_L
Pin 4 = 0v vss
Pin 5 =3.3 spi_mlb_mosi
Pin 6 =3.3v spi_mlb_clk
Pin 7 =0v spirom_use_mlb
Pin 8=3.3v vdd

 

[2informaticos]

"Pin 5 =3.3 spi_mlb_mosi
Pin 6 =3.3v spi_mlb_clk "
Looks like PCH doesn't access BIOS yet.
Check first PLT_RESET_L level.
Also check PM_PCH_SYS_PWROK.

 

[Chuck60]

Plt_reset_L =0v
Pm_pch_sys_pwrok =0v
What I don’t understand is if I’m missing pm_slp_s4_L
How can I have s3 State and if I don’t have s3 how can I have pm_pch_sys_pwrok or plt_reset_L can you give me a hint to where I’m going wrong I’m my thought process?

 

[2informaticos]

"Pm_Pch_pwrok=3.42v"
This should appear in S0 state.
So where is your error, missing PM_SLP_S4_L, or missing PM_PCH_PWROK???

 

[Chuck60]

I’m sorry it was pm_pch_pwrok =0v
I don’t have pm_slp_s4_L
I mistakenly wrote 3.42v on the first post.

 

[Chuck60]

Ok let me explain myself yesterday I was stuck around q7820 and
u7940
pin 1 = 3.285v smc_batlow_L
Pin 2 = 0v Ground
Pin 3 = 0v pm_sus_en
Pin 4= 0v pm_sus_en
Pin 5 = 3.3v pp3v3_s5
Pin 6 = 0 v Pm_slp_sus_L

q7820
Pin 1=0v pp3v3_sus
Pin 2 =0v pp3v3sus_ss
Pin 3 = 3.3v pp3v3_s5
pin 4= 3.3v pp3v3_s5

I was thinking this q7820 (I have gate and source but no output) was bad but I wanted Ask your input on my problem before I changed this. I’m sorry if I misunderstand the circuit

 

[2informaticos]

Don't worry about PM_SLP_S4_L: you have missing PM_SLP_SUS_L!!!
Post PM_DSW_PWRGD, PCH_DSWVRMEN, SMC_ADAPTER_EN, PM_RSMRST_L, PM_PWRBTN_L and all 4 RTC signals.

 

[Chuck60]

PM_DSW_PWRGD =3.27v
PCH_DSWVRMEN =3.15v
SMC_ADAPTER_EN=3.36v
PM_RSMRST_L=0v
PM_PWRBTN=3.42v

RTC signals

Sysclk_clk32k_rtc =0v
Ppvrtc_g3h=3.26v
Rtc_reset_L=3.24v
Pch_srtcrst_L=3.18v
Pch_intvrmen_L =3.2v
Pch_intruder_L=2.8v
Ppvout_g3_pch_dcprtc=0v
Are these the rtc signals you needed ?

Pm_slp_sus_L = 79ohms resistance to ground

 

[2informaticos]

"Are these the rtc signals you needed ? "
Missing two, PCH_INTVRMEN and PCH_INTRUDER_L.
I didn't ask about 32KHz oscillation, as requests o-scope to test it for sure.

"PM_RSMRST_L=0v "
Normal, I forgot about missing PM_SLP_SUS_L.

"Ppvout_g3_pch_dcprtc=0v "
Looks like PCH issue; there should be 1.5V I think.
Post the missing signals first...

 

[Chuck60]

Pch_intvrmen_L =3.2v
Pch_intruder_L=2.8v
I tested the sysclk_clk32k_rtc signal yesterday it’s was 32.6khz tested with oscilloscope
I’m still missing pp3v3_sus

 

[2informaticos]

"I’m still missing pp3v3_sus"
You cannot get it without PM_SLP_SUS_L.
As above mentioned, looks like you have a problem with the PCH.
Put quality flux and heat it; no more than 180-200 degress.
You don't need to melt the balls, just burn eventually accumulated crap underneath...

 

[Chuck60]

Ok will try thanks

 

[Chuck60]

Ok I’m gonna ask this I’m just lightly heating the cpu/pch at 180 degrees at a moderate air speed and don’t remove underfill and remove whatever crap is accumulated under it. Did I understand you correctly ?

 

[2informaticos]

Yes!
Removing the underfill from corners can help flux distribution...

 

[Chuck60]

Ok so let me ask you this if I boot in to OS X and the fan spins high all the time with an erratic mouse, keyboard is a little laggy . Is it most likely a heat sensor issue? I was guessing maybe it can’t sense the temp and runs it at high to compensate?

 

[Chuck60]

I’m checking r5271, r5270 and r5260, r5262, and the Vias for continuity.
it’s booting quickly and just buggy with trackpad and fan speed I’m gonna see if I find the asd efi for this board to help me narrow it down

 

[2informaticos]

The board started after heating PCH?
You should run ASD to detect sensor errors.

You can also try disconnecting webcam and changing trackpad board/flex.

 

[Chuck60]

I got it Q5501 and yes it’s all working now
Thank you so much for your help