acer VA30-HB no power

[nassih]

hi everybody a have an acer VA30-HB no power,the client informed me that the laptop had a display problem,work only on the external screen, after a few days it was no longer lit,
i have 5vALW but 3.3v no its coming and disappear immediately when i plug adapter in , no short, U4501 replaced too.someone had similar problem?

[nassih]

Re: acer VA30-HB no power

3.1v in power switch

[mcplslg123]

Re: acer VA30-HB no power

Try replacing PT4502 with 330uf. What is the resistance on 3V Coil??

[nassih]

Re: acer VA30-HB no power

diode mode red probe in gnd i have 0.360

[nassih]

Re: acer VA30-HB no power

pt4502 replaced with 330uf same problem,3.3v coming then goes off

[nassih]

Re: acer VA30-HB no power

maybe the cpu?

[mcplslg123]

Re: acer VA30-HB no power

maybe the cpu?

Very unlikely. You can remove the 3V coil and try injecting 3V on the output side of this coil. make sure you dont have any shorting in cpu vrm area specially high side mosfets before injecting voltage.

[nassih]

Re: acer VA30-HB no power

problem solved after replacing PR4502 resistor divider for creating VFB2,also the display problem was en LVDS connector LCD side it was damaged.
tanks community