Acer 5760G - Quanta ZRJ dead, no power

[MARHD]

Hi guys,

I'm trying to fix the laptop above. I have 19v I'm pretty sure, and I have 3v at certain places but not on the power button. This is super weird since I have 3v on one of the other buttons near it, the IC's near the power button are also missing 3v but some have 1.8 and 1.5v. The weirdest thing is that when i short two pins on the ic in thr picture the fan starts spinning but nothing else, when i dont short it, the fan has no voltage at its connector.

Please help, also does anyone have the boardview for this quanta ZRJ, I cant find it anywhere.

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

I forgot to mention that the power button has 1-1.2v instead of 3v

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

And here is the schematic if it helps

[mielta]

Re: Acer 5760G - Quanta ZRJ dead, no power

Hi
Messure the Powerbutton if he works OK . Multimeter on Ohm
Or desolder it and than messure again

[Techtiger]

Re: Acer 5760G - Quanta ZRJ dead, no power

I forgot to mention that the power button has 1-1.2v instead of 3v

mesure Voltage R18 both side's
mesure Voltage R418 both side's

[Techtiger]

Re: Acer 5760G - Quanta ZRJ dead, no power

Hi guys,

I'm trying to fix the laptop above. I have 19v I'm pretty sure, and I have 3v at certain places but not on the power button. This is super weird since I have 3v on one of the other buttons near it, the IC's near the power button are also missing 3v but some have 1.8 and 1.5v. The weirdest thing is that when i short two pins on the ic in thr picture the fan starts spinning but nothing else, when i dont short it, the fan has no voltage at its connector.

Please help, also does anyone have the boardview for this quanta ZRJ, I cant find it anywhere.

for the fan U21 power the fan power mesuer pin 2 for vin

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

The power button is working, the 1 volt drops to 0 if i preas it

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

mesure Voltage R18 both side's
mesure Voltage R418 both side's

I can't find them, and I don't have the boardview to do so

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

for the fan U21 power the fan power mesuer pin 2 for vin

The u21 is missing 5v, I'm not sure which is pin 2 but i checked all the pins and very low voltage on all pins, below 1v

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

Just to make sure, which are the two mosfets i can check for 19v on?

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

Ok for the one switch that was 3v it is now also 1v, not sure why. Also the led above the power switch has 3v, which is odd since it is so close

[Techtiger]

Re: Acer 5760G - Quanta ZRJ dead, no power

I can't find them, and I don't have the boardview to do so

in your Mob R18 not present
check pin 95 U22 SIO IC for NBSWON 3.3V
Check pin 19 & 102 u22 IC FOR 3.3V
Check PL 14 +3VPCU is stable

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

PL14 has stable 3.3v on both sides.
Pin 95 of u22 has 1v.
Pin 102 of u22 has 2.5v
Pin 19 of u22 has 2.5v
But pin 93 of u22 has 3.3v

[Techtiger]

Re: Acer 5760G - Quanta ZRJ dead, no power

you have to find out R418 & test input side for 3.3V it's near the SIO U22 near pin 19 & 102
send a cloe up PIC of that area it's near L26 Coil, there is a Voltage Drope, SIO nead 3.3V
Check your Bios Pin 8 for 3.3V U23

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

R418 has 3.3v on the U22 side, and 2.5v on the other side.
I checked the Bios pin 8 on the C586 capacitor, and it was 3.3v, the other side of the cap was low voltage. you can see on the pic

[ktmmotocross]

Re: Acer 5760G - Quanta ZRJ dead, no power

this can be shorted SIO or some output that draining too much current

remove l26 coil and other capacitors to be sure it is SIO that pulling that line down

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

this can be shorted SIO or some output that draining too much current

remove l26 coil and other capacitors to be sure it is SIO that pulling that line down

which other capacitors?
and what do you want me to test once i remove it?

[ktmmotocross]

Re: Acer 5760G - Quanta ZRJ dead, no power

on the side of that resistor where is voltage pulled down is not connected only SIO. so isolate that line from other components to be sure that SIO is the component that pulling voltage down

[MARHD]

Re: Acer 5760G - Quanta ZRJ dead, no power

on the side of that resistor where is voltage pulled down is not connected only SIO. so isolate that line from other components to be sure that SIO is the component that pulling voltage down

So remove L26 and C579? and then check the resistor again? Or remove all of these caps also?

[Techtiger]

Re: Acer 5760G - Quanta ZRJ dead, no power

this can be shorted SIO or some output that draining too much current

remove l26 coil and other capacitors to be sure it is SIO that pulling that line down

is that R418 faulty ?