ACER V3-471G no display NEED HELP

[xurplusxhop]

mobo comes with no power at all.

NBSWON# - only 1.3v

REPLACED NEW U20 (SLJ8C) and U17 (NUV0TON NPCE885LA0DX)

now NBSWON# - 3.36V

Pl6 - 2.65v
pl7 - 0.904v
pl8 - 1.065v
pl9 - 0.951v
pl10 - 0.951v
pl11 - 0.9v
pl12 - 0.9v
pl13 - 0v
pl14 - 3.24v
pl15 - 5.10v
pl16 - 1.514v


pu6 (tps51650)
pin:
17 - 3.37v
23 - 0v
16 - 3.33v
18 - 1.052V
19 - 1.051V
20 - 1.052V

PU8 (tps51601)
pin:
1 - 4.88v
2 - 5.04v
3 - 2.54v
5 - 0v
6 - 5.1v
7 - 0v
8 - 0v

SYS_PWROK - 3.3V
PM_DRAM_PWRGD - 3.3V

what should I do next? thanks

[xurplusxhop]

Re: ACER V3-471G no display NEED HELP

any help?

[meritosari]

Re: ACER V3-471G no display NEED HELP

did you test with internal or external screen?

[xurplusxhop]

Re: ACER V3-471G no display NEED HELP

yes. tried that already but still no display.

[pcnetch]

Re: ACER V3-471G no display NEED HELP

PM_DRAM_PWRGD - 3.3V good means, VGA fault. Is there a dedicated graphic chip or on board VGA? If on board try replacing CPU and ram also

[atsio]

Re: ACER V3-471G no display NEED HELP

PM_DRAM_PWRGD - 3.3V good means, VGA fault.

And why is that? How did you come to this conclusion?

[banchi99]

Re: ACER V3-471G no display NEED HELP

hi, bro. you have missing the +3v rail , pl13=0v and pin 23=0v. this voltage rail comes from mosfet PQ 17. +3V rail it is very important goes to PU6, Where voltages +vcc_core and +vcc_gfx come from. using as ivy processor power supply.

[atsio]

Re: ACER V3-471G no display NEED HELP

What is the resistance relative to ground on inductors pl11, pl12, pl13?
Why did you replace U20 and U17?