Dell xps m140 (pp19L)

[lezsimply]

Anybody got schematic for this old laptop dell XPS M140 PP19L. power turns off after 5 seconds. Thanks

[lezsimply]

Re: Dell xps m140 (pp19L)

motherboard code is 48 4C401 011.

[atsio]

Re: Dell xps m140 (pp19L)

[lezsimply]

Re: Dell xps m140 (pp19L)

Thank you atsio as always. I need help on reading voltages of charger ic, U6 on page 42 of schem. I'm lost from there.

Pin no.
1 -19.60v
2 -5.43v
3 -2.39v
4 -4.22v
5 -3.06v
6 -3.27v
7 -1.72v
8 -0v
9 -1.69v
10 -0v
11 -2.59v
12 -0v
13 -0v
14 -0v
15 -0v
16 -12v
17 -12v
18 -12v
19 -0v
20 -0v
21 -5.42v
22 -19.05v
23 -19.05v
24 -19.80v
25 -19.78v
26 -19.78v
27 -9.38v
28 -19.53v

Problem power tuns off after 5 secs. 3.3v present on power button. I'm still looking for short. Many many thanks

[cyberhack]

Re: Dell xps m140 (pp19L)

Check the usb ports

[lezsimply]

Re: Dell xps m140 (pp19L)

This laptop was working, before it was kept for 8 months since the owner bought a new one.

[lezsimply]

Re: Dell xps m140 (pp19L)

If laptop turns off after a few seconds does is always mean it has short on board?

[dj_ricoh]

Re: Dell xps m140 (pp19L)

change the bios battery and rewrite the bios.
I know when there is n channel mosfet on the first line when acin in over 1.5v acok must be low low ( 0v) but i don't know how it works with p channel like you have here

[xxxvirus1987xxx]

Re: Dell xps m140 (pp19L)

dont ignore bad capacitors better to replace it with a new one....
also cold solder...

[lezsimply]

Re: Dell xps m140 (pp19L)

@ dj

rtc battery is good. I don't think I can rewrite bios I don't have 40-pin adapter for that.

@virus

I'm still looking for shorts. I have resoldered dozens of caps and transistors. Tested most of them and found no short. Used 3 different original adapters. Usb ports are all ok.

thanks guys!

[atsio]

Re: Dell xps m140 (pp19L)

Check resistance on all coils to ground