820-4924-A No USB activity 330ma

[TBFix]

I have checked down to s0 voltages all are present, ppbus_g3h is 12.59v.
When Powered up it draws 330ma and then fan comes on full speed. Cpu heats but no usb activity. No sign of spillage.
I checked Spi term resistors all ok.
Charger led turns from green to orange.
I tried several efi dumps with clean me.
ALL_SYS_PWRGD is 3.3v
Pm_S0_PWRGD 3.42v
Pm_SLP_S4_L is 3.3v
SYSCLK_CLK25M_X2 is good
CPUVR_PHASE1 and phase 2 are 1.8v
PCH_DSWVRMEN 3.2v
PCH_INTRUDER_L 3v
PCH_INTVRMEN 3.3v
RTC_RESET_L 3.3v
PCH_SRTCRST_L 3.3v
PM_BATLOW_L 3.3v
PM_DSW_PWRGD 3.4v
SMC_ADAPTER_EN 3.3v
PM_RSMRST_L 3.2v
PM_PWRBTN_L 3.4v
SMC_RESET_L 3.4v

Any help appreciated

 

[piernov]

PLT_RESET_L?

 

[TBFix]

Apologies forgot about that one
PLT_RESET_L is 0v
PM_PCH_SYS_PWROK 0v
PM_SYSRST_L 3.3

 

[piernov]

Check for liquid damage/corrosion on U1950. Check voltage on all pins of U1950.

 

[TBFix]

No obvious damage . I replaced U1950 and still the same 330ma and fan on constant full speed.
pin 1 3.3
pin 2 3.3
pin 3 0v
pin 5 3.4
pin 6 0v
pin 7 3.4v
pin 8 3.4v

 

[2informaticos]

Tie together pin 5/6 and check if board works.

 

[piernov]

Check resistance to ground and diode mode to ground on SMC_DELAYED_PWRGD.

 

[TBFix]

Check resistance to ground and diode mode to ground on SMC_DELAYED_PWRGD.

.653

Tie /6 together no change. any point in changing /reflowing SMC?

 

[2informaticos]

Reball/replace SMC...

"Tie /6 together no change"
I suppose you mean "5/6"; pin 3 goes high then?

 

[TBFix]

Yes pin 3 goes high but still 330ma and fan runs full speed

 

[2informaticos]

PLT_RESET_L goes high too?
If yes, try known good BIOS.

 

[piernov]

Sounds like SMC issue if SMC_DELAYED_PWRGD doesn't come up.

 

[TBFix]

Yes PLT_RESET_L goes high. I replaced the smc and now
SMC_DELAYED_PWRGD 3.3v
PLT_RESET_L 3.3v.
Still no usb activity

Also tried known good bios

 

[2informaticos]

Then should be CPU issue.
You can try heating it with quality flux, just in case.