Laptop Motherboard Repair

[momaka]

Re: Laptop Motherboard Repair

What you need is a low-voltage, high-current source, preferably sub 3V and able to supply at least a few amps.

Probably what you want to do is find the part\branch of the circuit where you have found the short, verify there is in fact not supposed to be a short, and apply power there, and see what happens.

Correct.

However, be cautious with this method. CPU, GPU, and Northbridge power rails will more often than not appear shorted or with very low resistance. This is actually normal in most cases. Applying power on those rails with too high of a voltage can damage the CPU, GPU, or Northbridge.

Can anyone give a brief explination of how to use a bench supply to "smoke" out the shorted componant ? i know its probably not good practice but i have a couple of boards that i have extensively tested with my meter but have been unable to find the shorted part

The problem you have with those boards may not necessarily be shorted components. It could also be a bad connection, bad GPU or Northbridge BGA joint, open resistor (good luck finding that!), bad ICs, or an internally bad trace. In any of the above cases, a bench power supply won't help you much, other than to further damage the board and conclude it's dead.

[bazzbarro]

Re: Laptop Motherboard Repair

hi have Toshiba satellite not powering on the led would blink a little when power supply first inserted or battery but would fade out kindly inform on the primary power testing points tips

[lord]

Re: Laptop Motherboard Repair

Hi bazzbarro!
First please use . and , because they are essentials to good communication.
Secondly you have to specify model of the laptop in order somebody can help you. It is also good to put the pictures of disassembled motherboard so we can understand each other better.
Regards to Kenya!
Darko

[bazzbarro]

Re: Laptop Motherboard Repair

dell latitude d610 gives this erro
****manufacturing mode :[67]****
press fn-x to return the system to normal running mode

[bazzbarro]

Re: Laptop Motherboard Repair

dell latitude d610 gives this error i would kindly like to know which component on the m b can be repaired have tried all the basic tips on forum fn x bios settings test all memory's etc

****manufacturing mode :[67]****
press fn-x to return the system to normal running mode

[bazzbarro]

Re: Laptop Motherboard Repair

dell latitude d610 gives this error i would kindly like to know which component on the m b can be repaired have tried all the basic tips on forum fn x bios settings test all memory's etc

****manufacturing mode :[67]****
press fn-x to return the system to normal running mode

[bazzbarro]

Re: Laptop Motherboard Repair

sorry for my broken English i will try to cultivate it the model is satellite A100
about the images am unable to get them right away because its for client and i had returned it back before i get the tips and how to get started working on it i have good background on electronics so before i get the images where to begin

[sasser]

Re: Laptop Motherboard Repair

U see the bios setting before this error? Try to flash new bios

[bazzbarro]

Re: Laptop Motherboard Repair

u cant see anything even the dell logo this black screen just pop up

[oxonater]

Re: Laptop Motherboard Repair

Hi I was wondering if anyone knows about this issue I have with the following laptop.

Toshiba Satellite P200-1EE
Model no:PSPB6E-0GMO28EN
K000057590

The LCD is blank and only get a mere white flicker stays blank as laptop continues its boot up process. I have changed the Inverter and no joy, I have a working backlight out of a smashed screen and when connected into a tested Inverter it doesn't light up at all. The laptop will work fine when connected to an external display. Have been told that this issue relates to a faulty power fet that supplys power to lcd circuit.
Any help would be great thanks

[spleenharvester]

Re: Laptop Motherboard Repair

Guys, would a 5v 1A wall wart that's been chopped up be good for "heat testing" for shorts?

Also anyone got any guides as to where to start? How to test FETs, ceramic caps, readings you'd expect to see on an ohmeter etc?

Cheers

[severach]

Re: Laptop Motherboard Repair

Wall warts are no good for short testing. 1A might be enough to burn the short out. Any more than 1A and the supply will shut down.

A bench supply won't shut down and allows you to control the current so you can get the shorted component to heat up without burning it up. Meters are good too so you know about how much heat you're looking for.

[yadab100]

Re: Laptop Motherboard Repair

Dear Friends,
My toshiba laptop problem is 3,5 volt always is ok, core plus every power is ok, clock also good(means same with diagram), but power on , fan run, cpu heating, , but not displaying, after that copy bios software but same status, What can I do ? I think BGA Chip & Controller is bad but how can we fix is this bga problem & others.....

[sasser]

Re: Laptop Motherboard Repair

Guys any tips or trick howto know that bga is shorted when solder underneath is cold solder bad join or uncut together? Most cases gpu or southbridge is problem.

[severach]

Re: Laptop Motherboard Repair

Shorted chips usually heat up when current is supplied to the short. Heat sinks make the heat hard to find. Some good chips will overheat if they are powered by only some of their voltages.

[trebo]

Re: Laptop Motherboard Repair

Guys any tips or trick howto know that bga is shorted when solder underneath is cold solder bad join or uncut together? Most cases gpu or southbridge is problem.

I set up the m/b on a table, screen connected
press down on the chip and the opposite side of board hard, so that it is sandwiched between my fingers
have someone turn it on long enough for screen to come on, if screen does not come on then it must be turned off, then turned straight back on
keep repeating this process about 6 times while chip is pressed from both sides of board hard and continually (sometimes it works first time)
the screen at some point will come on if it is the offending chip, (on most occasions)
care must be taken to ensure that you do not short m/board out, tape and cardboard help to prevent this for me.

also a hair dryer aimed at the underside area of the chip from the other side of the m/b, with someone else turning m/b on and off, the same as the first method
this option works well in bringing the screen on, It tells you there is a dry joint etc, but heat travels so you cant be 100% sure its the chip you are working on
that's one is for you to make up your own mind on
hope it helps

[sparker1]

Re: Laptop Motherboard Repair

Since everybody bags out reflows I was thinking of a reball kit including an IR station. There's this one in my price range. What do you think of it?
http://www.aliexpress.com/item/New-T...466034161.html
and also this one (previous model I think)
http://www.aliexpress.com/item/The-B...320954931.html
I saw a post here that said this one wasn't good for laptops but didn't say why.

[Agent24]

Re: Laptop Motherboard Repair

I don't know for sure but I don't think the IR lamp has a wide enough beam on those models to properly heat up large BGAs that are usually found on motherboards.

I think those ones are designed more for phones and other similar devices where the chips are quite small.

I may be wrong but that was the impression I got from what I've seen online, eg: The demo videos and photos always show that model station used to repair phones.

[senchire]

Re: Laptop Motherboard Repair

If you plan on doing laptop, ps or xbox reflow/reball with T862 its a bad idea.
Low power, small heater and bad quality all in one (i would say). You will have a lot popcorned chips and wraped boards, you are new to the scene (i guess maybe wrong) a good IR preheater and a hotair wand is the perfect if you don't wanna spend a lot of money.

[sasser]

Re: Laptop Motherboard Repair

At least u need some machine like ir6500. This enough then u upgrade to elstien heater