Laptop Motherboard Repair

[Heracles]

Re: Laptop Motherboard Repair

Hello!
I have a problem with an Acer 3610 motherboard. There is no video on the LCD, only on an external screen. I have tested with two different sets of LCDs and inverters and they are tested ok with a similar motherboard. If I connect an external screen, even without a keyboard connected, the image is displayed on the external screen after 1 second.

It seems to me that the system checks if the LCD is connected, fails to detect one, and then routes the display to the VGA-port instead. I have tried to drive the inverter with an external source, just to see if the problem is related to the backlight not working, the CCF-lamp lit, but there was no image.
Does anyone have an idea what to check for?
Eric

[insomnia]

Re: Laptop Motherboard Repair

is there any chart around or link around that shows all different types of smd smt components after looking at this post i was checking the little small 3 legged things but seen a picture of mosfets on a board there in this post and was very surprized any know were i could get to know all the different components

[precision001]

Re: Laptop Motherboard Repair

Laptop drawing exactly half of normal current before power button pressed. No change after button pressed, no sign of life. What could this be? Bad FET?

[rop12770]

Re: Laptop Motherboard Repair

Hello

Finally after a great search, I have found the FORUM that I need.

I have been reading this post about laptop motherboards and I was very excited with the help that is given.

I work with computer for about 13 years, but not reparing components. I changed the malfunctioning part, but now I'm very interested in solve some problems especially with laptop boards.

I'm very newbie. Can you guys show me the way of troubleshoting?
Where should I start?

Thank You

[precision001]

Re: Laptop Motherboard Repair

The problem is figuring out what that shorted part is. I happen to have an identical board here, that has other issues. I have my new dark infrared station, so I'm going to remove and replace each part, one by one, until (hopefully) I find the bad part. It's gonna suck but, that's how you learn.

[momaka]

Re: Laptop Motherboard Repair

I replaced the 4825p mosfets, but the problem remains. One of the mosfets still shows shorted on all pins. I'm not sure where else to look.

Try removing the MOSFET first and then test it for shorts. If it shows none, there is something else shorted on the board.

[precision001]

Re: Laptop Motherboard Repair

3 seconds then off? Sometimes reballing does the trick. But there are some cases when the gpu has nothing to do with it. I'm still trying to determine that myself.

[TECHMECH]

Re: Laptop Motherboard Repair

I too wish there was a mosfet cross reference guide. So far I have the best luck finding out which manufacture they are and finding the datasheet. Probably best to replace it with the same though. I would check the caps and mosfets near the shorted inductor first. However you may find that it is an IC shorted, then things get tricky, I have trouble with this myself. I would definitely replace that mosfet showing 0 across the board. Do you have any experience with dv6/9000s that power on for about 3 seconds then power off. I have a stack of 10 that are all doing this, no shorts, reflowed, even replaced the NB on a couple. They are the MCP67xx Chips. The one with north and south combined. Im thinking one of the maxim chips or the clock controller? Any suggestions?

[precision001]

Re: Laptop Motherboard Repair

DV6000 No Power - Blue DC Block lights..

Low ohms

181 ohms - 7636 (By 8724)

51 ohms - 7636 (by ENE)

274 ohms - 6679 (opposite side of CPU socket)


Replace all? This version of the board uses an intersil SMPS controller. How would I test it? ISL6236

[precision001]

Re: Laptop Motherboard Repair

I replaced the 4825p mosfets, but the problem remains. One of the mosfets still shows shorted on all pins. I'm not sure where else to look.

[precision001]

Re: Laptop Motherboard Repair

If a mosfet is shorted, would it show zero ohms between all pins? I have another motherboard with no power, and found a mosfet with zero ohms between all of it's pins, so I think it's bad. It's labelled 4825p. I'm going to have to try to find a suitable replacement for that one. I wonder if there is a cross-reference guide of some kind for these. I'm going to do the same check for this DV6000, and check for shorts like you say between inductors and ground. If I detect zero ohms between an inductor and ground, what would be the next logical step?

[TECHMECH]

Re: Laptop Motherboard Repair

Hello, I would check for a short between inductors and ground, then check for a shorted transistor in the power on signal circuit.

[precision001]

Re: Laptop Motherboard Repair

I have an AMD based DV6000 motherboard in pristine condition. No power. No burnt mosfets, and no caps appear to be broken/shorted. When connected to a power jack, the LED indicator lights, indicating that there is no short, at least not in the beginning of the power circuit. Where would you recommend I begin?

[precision001]

Re: Laptop Motherboard Repair

How did you know that part was bad? What problems was the DV6k exhibiting? Was the repair successful?

[aubrey52]

Re: Laptop Motherboard Repair

STJ thank lot
i found that out and order 3 from digkey
32.768ke
got in to day fix mother board
here is digkey part number SE2417CT=Nd
95 cent a prics
thanks
aubrey52

[stj]

Re: Laptop Motherboard Repair

that's just a watch crystal.
32.768khz is a time standard.
*any* old motherboard will have one.

[aubrey52]

Re: Laptop Motherboard Repair

can you help me out dead laptop motherboards hp dv6000/6131od 434723-001
i need parts y6 on motherboard by backup battery. number on part
is 32.768KE i thank it a crystal
thanks
aubrey52. have a good day

[precision001]

Re: Laptop Motherboard Repair

Based on some information that I have collected, the unidentified 16 pin chip is a PWM controller manufactured by Intersil. That might explain why all the caps on the PCB opposite the CPU are showing shorted (with no power applied, of course). I wouldn't be surprised if the CPU itself is bad, but that's no big deal. The problem now is that I need to find another PWM controller, or this will never boot up again.

[precision001]

Re: Laptop Motherboard Repair

I removed the first burnt 8 pin mosfet. I can't read what type it is, but the top of it says ph7sd.

[Pyr0Beast]

Re: Laptop Motherboard Repair

It is better to verify it twice.