Dell alienware c912p rev 2.0 dead

[ritch50]

Hi, hope somebody can help. Noob here.

Dell Alienware 15 LA-C912P REV2.0 laptop here that I have No history of. Don't know what previous has happened just dead no power at all.
The only thing I can find is what looks to be a burnt resistor? I cannot see the value, have attached the pic.
The laptop does not power at all, nothing. There is 19V at 1 side of the resistor, 0.89 at the other.
Any pointers would be amazing please!

Thank you and good health, Rick

[peste]

Re: Dell alienware c912p rev 2.0 dead

see which route has the resistance part with 0.89v, if it reaches pin 28, CI PU 700, the resistance has 10 ohms.

[ritch50]

Re: Dell alienware c912p rev 2.0 dead

Hi Peste, thank you for your reply!
I found this with multimeter:
pin 28 vcc 0.86v
pin 6 acdet 2.57v
pin 5 acok 0.19v
pin 4 acdrv -0.05v

Do you think that it is just a burnt resistor causing fault?

Thank you,
Ritch

[mcplslg123]

Re: Dell alienware c912p rev 2.0 dead

That resistor is burnt for sure as you are aware. Remove it from m/b. check resistance on the side where you get 0.89V. You need to replace the resistor as @peste suggested but do check resistance on 0.89V side. If there is short on the 8.089v side, resistor will burn out again.

[ritch50]

Re: Dell alienware c912p rev 2.0 dead

Hi mcplslg123,

Thanks for the reply, I checked and no short it appears so replaced the 10 ohms resistor and it dosen't burn out so 19v going to pin 28 but still dosent fire up

Thanks, Rick

[emestee]

Re: Dell alienware c912p rev 2.0 dead

What about ACOK and ACDRV?

[ritch50]

Re: Dell alienware c912p rev 2.0 dead

What about ACOK and ACDRV?

Hi


ACOK : 0v
ACDRV: 0v

:-(

[emestee]

Re: Dell alienware c912p rev 2.0 dead

Hi


ACOK : 0v
ACDRV: 0v

:-(

So the charger IC won't start, look in its datasheet how ACOK is formed, and it'll tell you where the problem is - or that the IC is dead. The first place to look would be the minimal voltage on ACDET, and whether the LDO output of the IC is shorted.