A1278 820-2936-B Missing PP5V_SUS

[Amraks]

All important voltages are there

So noticed I have no voltage here
PM_SLP_SUS_L 0.00v

and have voltage here I understand this is a operator value for u7040 and PM_SLP_SUS needs voltage to turn on.
SMC_BATLOW_L 3.30v

These are voltages measurements I have taken I am unsure if this is a problem with PCH or SMC
SYSCLK CLK32K RTC 0.81
RTC RESET L 3.30v
PHC SRTCRST L 3.30v
PCH INTRUDER L 3.015v
PCH INTVRMEN L 3.22


PPVRTC_G3H 3.3v
RTC_RESET_L 3.30v
PCH_SRTCRST_L 3.30v
PCH_INTVRMEN_L 3.22v
PCH_DSWVRMEN_L 3.20v
SYSCLK_CLK32K_RTCX1 0.81v
PP3V3_S5 3.40v
PM_DSW_PWRGD 3.47v
PP3V3_SUS 0.00v
PM_BATLOW_L 0.12MV
PM_RSMRST_L 0.00v
PM_PWRBTN_L 3.47v




PP3V3_S5 3.41v
PP5V_S3 0.00v
P5VS3_EN_L 3.45v
PM_SLP_S4_L 0.00v

ADAPTER_SENSE 3.40v
SMC_ADAPTER_EN 3.46v


PM_SUS_EN 0.00v
P5VSUS_EN_L 4.89v
P5VSUS_SS 4.89

PP5V_S5 5.0v

PP5V_SUS 0.060v

PM_SLP_SUS_L 0.00v
SMC_BATLOW_L 3.30v

PPVRTC_G3H 3.33v

5V3V3_REG_EN 3.42v

P3VS5_LL 3.341V

P3V3S5_VBST_R 7.67V

P3V3S5_VBST 7.67V

P5VP3V3_REG3 3.34V

P3V3S5_ENTRIP 0.731V

P3V3S5_VFB 2.35V

P5VP3V3_REG3 3.34V

P5VP3V3_VREF 2.01V

P5VS3_VFB 0.00V

P5VS3_ENTRIP 0.00V

P5VS3_VO1 0.00V

P5V3V3_PGOOD 0.00V

P5VS3_VBST 3.53V

PS5VS3_DRVH 0.00V

P5VS3_LL 0.00

P5VS3_DRVL 0.00V

PPBUS_S5_HS_OTHER_ISNS 12.63

P3V3S5_EN_L 0.00V

P3V3S3_EN_L 3.3V

[mon2]

Re: A1278 820-2936-B Missing PP5V_SUS

For the rails that you suspect to be incorrect, remove all power, meter in resistance mode (lowest scale).

Check the resistance to ground for that rail.

Post the resistance reading.

[Amraks]

Re: A1278 820-2936-B Missing PP5V_SUS

Resistance
pm_slp_sus_l is 94.5k

[Amraks]

Re: A1278 820-2936-B Missing PP5V_SUS

I have solved this problem it was under PCH I pushed some flux under chip and heated with hot air at 200c.
Then flooded under chip with alcohol and went back over with hot air.

I had given up on fan spin and left it connected while I stepped out to the shop only to find it was still hot when I got back so I disconnected it and connected fan then had the fan spin.

Reassembled laptop and it's fixed. Not sure how long or what was going on with PCH chip, laptop has been refurbished apparently so who knows what's been fixed on it before.

But gave it hot and cold starts all week and it didn't fault once.