Dell XPS M1530-Shorting out Adapter

[kev4eva]

Got a dell xps m1330,

Seem to be a power protection problem, cant find the source of the short.
The board is shorting out ac adapter when i try to plug in.

Tested U41 and U42 mosfets, they seem ok, C10 capacitor ok too.

Stuck on pg 38 of schematic....any help please??


See link....Will try get some pics


Dell Xps M1330 Intel Motherboard Schematics

[whaldsz]

Re: Dell XPS M1530-Shorting out Adapter

Resistance to ground of test point +DC_IN?

Voltage of U40. At pin 1, 4 and 8?

[Sparks88]

Re: Dell XPS M1530-Shorting out Adapter

try the decoupling ceramics on the video board, there are several in a line along one edge of the board and one of these will be short circuit

[kev4eva]

Re: Dell XPS M1530-Shorting out Adapter

Resistance to ground of test point +DC_IN?

Voltage of U40. At pin 1, 4 and 8?

u42 pins 1,2,3 short to ground.............cant test voltage as adapter keep shorting out and i dont have dc power supply

what you think, u42 short or its a cap nearly, from the schematic arent those pins positive???

[robrock1]

Re: Dell XPS M1530-Shorting out Adapter

if you don't want to mess up your board use the multimeter and a dc power supply to test, i am sure just one of the small orange capacitors has been shorted so its easy to fix but if you try something you will end up damaging the board completely

[kev4eva]

Re: Dell XPS M1530-Shorting out Adapter

if you don't want to mess up your board use the multimeter and a dc power supply to test, i am sure just one of the small orange capacitors has been shorted so its easy to fix but if you try something you will end up damaging the board completely

try to source a dc power supply dont have one, jus a meter and a smd capacitor an resistor test but had to test these caps in the board

[robrock1]

Re: Dell XPS M1530-Shorting out Adapter

if you see some coil or mosfet is shorted, remove and check from which side the short is coming from then you trace it.

[kev4eva]

Re: Dell XPS M1530-Shorting out Adapter

if you see some coil or mosfet is shorted, remove and check from which side the short is coming from then you trace it.

i removed u42 then i see no short on adapter, i didnt turn on cause did want to damage anything.....waiting on your feedback

[robrock1]

Re: Dell XPS M1530-Shorting out Adapter

you have to see on which side of u42 is the short (on the motherboard then you search from there), or if u42 is shorted (use meter to test) try and find replacement for it or the laptop will not work

[dj_ricoh]

Re: Dell XPS M1530-Shorting out Adapter

resolder back u42 and desolder q6 and check again

[kev4eva]

Re: Dell XPS M1530-Shorting out Adapter

you have to see on which side of u42 is the short (on the motherboard then you search from there), or if u42 is shorted (use meter to test) try and find replacement for it or the laptop will not work

ok thanks guys...u42 reads ok out of the board, trying to find out more as you said

[kev4eva]

Re: Dell XPS M1530-Shorting out Adapter

resolder back u42 and desolder q6 and check again

here are my results:

i resodlered back u42 & desolder q6= adapter still shorts out.

still trying to find out whats causing diode u42 to short

[whaldsz]

Re: Dell XPS M1530-Shorting out Adapter

try to remove R340 and check pin 1,2,3 of U42). If it is still short, then check CH1. If U32 is no longer shorted, trace +PWR_SRC rails for shorted capacitor. You need bench PS to easily pinpoint it.

[Francisco.s]

Re: Dell XPS M1530-Shorting out Adapter

still trying to find out whats causing diode u42 to short

If u42 reads ok out of the board, it isn't in short-circuit, there must be mosfet, or a short-circuited capacitor.

[dj_ricoh]

Re: Dell XPS M1530-Shorting out Adapter

I got a xps like this so I will subscribe :-)

[Turbolego]

Re: Dell XPS M1530-Shorting out Adapter

Hello.

Sorry for necroposting this thread back to life, but i have the same problem with a M1330 (model PP25L)

Same symptoms, the indicator light on the power-brick shuts off if i plug it into the board.
I have tested the power brick with another computer (it works).

The machine has been taken apart, and the board is currently only connected to the CPU and power button board.

Anyways, i guess i need to get myself a multimeter to check for the bad caps, but what else should i get in order to do a proper repair?

Thanks in advance.

[hansie55]

Re: Dell XPS M1530-Shorting out Adapter

Hey,
What I mostly do: use a heavy adapter, 120-140W that keeps supplying with the shortcut and feel for hot components. In this case it is mostly a C or mosfet around C520 till C525
or at the four mosfets at U66.
This is realy the fastest way

[Turbolego]

Re: Dell XPS M1530-Shorting out Adapter

Hey,
What I mostly do: use a heavy adapter, 120-140W that keeps supplying with the shortcut and feel for hot components. In this case it is mostly a C or mosfet around C520 till C525
or at the four mosfets at U66.
This is realy the fastest way

Alright, so i need a new power adapter that doesn't shut itself off?

Hm... perhaps it will be cheaper to just get a new motherboard, i've seen a couple on ebay for $50.

I've also seen a lot of bad motherboards on ebay for $35 and up, lol

Might be the easiest way out, get a new board and sell the bad one for $10 and let someone else who has the proper equipment fix it.

[hansie55]

Re: Dell XPS M1530-Shorting out Adapter

Your choice.
I bought a universal adapter 140W for € 19,95

[rldator]

Re: Dell XPS M1530-Shorting out Adapter

We had the same model laptop but U40 mosfet burn-out. I replaced the mosfet 3 times and when I plug the adapter it burn again. What is the causes of this problem?