ASUS FX505DT w/ FX505DD Mobo - Not Turning On

[MobsterLobster]

As per title, when battery is connected or jack connected: keyboard light flashes once but cannot turn laptop on. Holding power button for 10 seconds then the KB backlight will flash again. Unknown history and signs of previous repair (jump wire from CMOS battery holder positive terminal to R2453, presume broken trace under it)

Thermal camera at board, 3 points warming up (not hot, just warm). CPU, BQ chip and ethernet controller. I guess this is OK??
- Ethernet chip I guess is powered for wake on lan functionality?
- BQ chip is driving input mosfets
- CPU warming as communicating with EC?

These voltages are all present:
- 1.8VO / 3.3VO / 5VO
- 0.9VSUS / 1.8VSUS / 3VSUS / 5VSUS / 12VSUS
- VDD18_ALW / VDD33_ALW / VDDIO_AZ / VDDP_ALW
- 3VA_EC / 3VAPPL
- +RTC_POWER is 3.3V
- RSMRST# is 1.8V

NOTES:
- No apparent short on EC 3V.
- VSUS_ON is present so presume EC working (VSUS_ON_EC output)
- No 3VS/5VS etc, they require SUSB#_PWR and SUSC#_PWR
- PM_SUSB# low 0v
- PM_SUSC# low 0v

Is my understanding of SUSB/C correct and that it's low to "SUSpend" those voltage rails and high to enable?
Can anyone give me advice on what I'm doing wrong or have overlooked.

[mcplslg123]

If you have DSO,check whether SUSB# & SUSC power rises for a brief second and then falls.
Measure resistance to GND on SUSB# and SUSC#.
Resistance to GND on 3VS/5VS.
Try disconnecting Keyboard and shorting the kbd connector pins to power on.

[MobsterLobster]

Thanks for your input, I forgot to include the measured inductor resistances I have taken:
INDUCTOR/OUTPUT = OHMS
L8100/5V0 = 16.3K ohm
L8101/3VO = 126 ohm
L8002/VDDCR_CPU_SOC = 4.9 ohm
L8001/L8002/VCORE = 3.3 ohm
L8201/0.9VO = 92.5 ohm
L8300/1.2VO = 93.2 ohm
L8700+L8701/NVVDD = 0.7 ohm
L8900/FBVDDQ = 96.5 ohm
L8800/BAT_R = 31.85K ohm
L8401/1.8VO = 30.7 ohm

And the ones as requested
3VS = 3.37Kohm (at Q9106 mosfet)
5VS = 0.95Kohm (at Q4806) (also, 12VS = 10Kohm)
SUSB#_PWR = 4.4Kohm (at D8325 pin2 - NOT populated) (4.4Kohm S3 on pin 1)
SUSC#_PWR = 4.7Kohm (at D8324 pin2 - NOT populated (14.7Kohm S5 on pin 1)

- I do not have a good oscilloscope (only cheap automotive style probe scope), not detecting anything on SUSB/SUSC, just stays low always.
- With keyboard disconnected and jump from PWR_SW# to ground it gives same results as power button press (no power on, flashes keyboard every ~10 seconds)

[alfredposadas09]

Thanks for your input, I forgot to include the measured inductor resistances I have taken:
INDUCTOR/OUTPUT = OHMS
L8100/5V0 = 16.3K ohm
L8101/3VO = 126 ohm
L8002/VDDCR_CPU_SOC = 4.9 ohm
L8001/L8002/VCORE = 3.3 ohm
L8201/0.9VO = 92.5 ohm
L8300/1.2VO = 93.2 ohm
L8700+L8701/NVVDD = 0.7 ohm
L8900/FBVDDQ = 96.5 ohm
L8800/BAT_R = 31.85K ohm
L8401/1.8VO = 30.7 ohm

And the ones as requested
3VS = 3.37Kohm (at Q9106 mosfet)
5VS = 0.95Kohm (at Q4806) (also, 12VS = 10Kohm)
SUSB#_PWR = 4.4Kohm (at D8325 pin2 - NOT populated) (4.4Kohm S3 on pin 1)
SUSC#_PWR = 4.7Kohm (at D8324 pin2 - NOT populated (14.7Kohm S5 on pin 1)

- I do not have a good oscilloscope (only cheap automotive style probe scope), not detecting anything on SUSB/SUSC, just stays low always.
- With keyboard disconnected and jump from PWR_SW# to ground it gives same results as power button press (no power on, flashes keyboard every ~10 seconds)

have you try to check the crystal oscillator?

[MobsterLobster]

have you try to check the crystal oscillator?

No I haven't checked it. Might be time for me to buy an oscilloscope...

- VBUS_ON output (output from EC)
- Working LED indicators (output from EC)
- Working BQ controller input mosfets
I assume it to be working based on these, is this a poor assumption?

[MobsterLobster]

Update:
- Confirmed 32Khz at X2401, but can't confirm the 48Mhz at X2402 (Out of range, cheap scope picks up something oscillating but can't measure it).
- Jumped J9301 test jumper to enable SUSB#. This gives 12VS which then enables 1.8VS and 3VS.

[MobsterLobster]

Schematic and boardview if needed

https://www.badcaps.net/forum/troubl...proper-fz-file

[MobsterLobster]

I think this board has a dead/shorted cpu. I flashed the bios with a couple of different versions with same result. Measured a bunch more and found nothing concerning.

Decided to recheck with thermal camera, see pics attached. First pic shows the cpu warming and in the corner is the BQ chip and the mosfet/inductor it controls. Second pic is a closeup of the cpu and can see the hot spot is a single small point coming out the side of the die. Would you agree this is likely the issue based on everything else?