Acer E1-470 EA40-CX 48.4LC03.031 Fan runs no picture

[KappaDev]

Hello, I have a Acer E1-470.
Motherboard: EA40-CX 48.4LC03.031
Schematics attached...

Originally wouldn't turn on due to short on 19V rail.
C4910 on DCBATOUT_LCD was shorted to ground, after removal the blue power LED lit and fans run at full speed but no video on display.

Here are the sequence of events:
Press power button ->
Blue power LED lights (PLED1)
Fan spins at low speed for ~10 seconds
Fan shuts off for ~20 seconds while PLED1 still lit
Fan runs at full speed until holding power button/disconnecting power

S0 Power Rails:
Plane Measured
5V_S0 == 5.156V
3D3V_S0 == 3.362V
1D8V_S0 == 1.830V
1D5V_S0 == 2.141V
1D05V_VTT == 1.042V
VCC_CORE == 0V
VCC_GFXCORE == 0V
DCBATOUT_LCD == 19.5V
DCBATOUT == 19.5V

If it helps:
PWR_VCORE_BOOT1 == 4.788V
PWR_VCORE_UGATE1 == 0V
PWR_VCORE_PHASE1 == 0V
PWR_VCORE_LGATE1 == 0V

I also noticed the chip 7718W thermal sensor looked like it was blown. (Picures attached)
The CPU stays cold and the fan runs at 100% speed the whole time.
Could this be a bad CPU maybe bad thermal sensor chip? Would a bricked BIOS cause 0V on VCC_CORE?
First post here, please advise if needs edits. Thank you!

[mcplslg123]

Re: Acer E1-470 EA40-CX 48.4LC03.031 Fan runs no picture

7718W seems blown. Measure voltage and resistance on all pins of 7718W. If the resistance is low or shows short, remove the chip and measure the resistance on all pins again.PM_SLP_S3# AND SLP S4# present??What about s0_pwr_good??

[KappaDev]

Re: Acer E1-470 EA40-CX 48.4LC03.031 Fan runs no picture

7718W seems blown. Measure voltage and resistance on all pins of 7718W. If the resistance is low or shows short, remove the chip and measure the resistance on all pins again.PM_SLP_S3# AND SLP S4# present??What about s0_pwr_good??

Yep, 0 ohms between Vdd and GND on 7718W... When removed 280 ohms.

PM_SLP_S3_ = 3.389V
PM_SLP_S4_ = 3.389V
S0_PWR_GOOD = 3.362V

Thanks for your help

[mcplslg123]

Re: Acer E1-470 EA40-CX 48.4LC03.031 Fan runs no picture

Now, you need to get a replacement for 7718W.