Laptop issue (technical)
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previously known as wrxBRAH
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Laptop issue (technical)
I know we have some geniuses on this forum so here goes....
I noticed last week that my laptop power cord wasnt charging (green led on the converter wasnt lighting up) so i swapped power outlets and then it started working. Fast forward to later on that evening I was eating chicken soup and i spilled some on the laptop mouse pad.
After I cleaned everything up I noticed my laptop was turned off. I go to turn it on and it shuts off after a few seconds. At this point I bust out the phillips and start taking it apart and let a small fan air it out for a few hours. When I put it back together I noticed it was still doing the same thing but *ONLY* when the power cord was connected and it wasnt charging when off (charging led on laptop wasnt turning on).
After cursing a bit I decided to take the entire thing apart and noticed the stain on the motherboard from the chicken soup. I cleaned it with rubbing alcohol and put it back together one more time. At this point the computer powers up and runs with the power cord connected but still doesnt charge. I checked the charging connector when it was taken apart and everything looked good. (didnt notice any cut wires or soldering issues) At this point I went and started checking the power cord with a voltmeter and the converter/cord is working (19.4Volts are coming at end).
Decided to go to frys today and check out power cords anyway and even with a new one it still wont charge. Its obviously not a battery or power cord issue. I think its the motherboard but Im unsure of how to test the charging circuit on a motherboard or even if its something I can fix. Can anyone shed some light for me on this? I dont really want to spend 400-500$ on a new motherboard if its something I can fix by myself for a lot less.
As always any help or input is greatly appreciated.
Cliffs: Laptop busto!!!!
I noticed last week that my laptop power cord wasnt charging (green led on the converter wasnt lighting up) so i swapped power outlets and then it started working. Fast forward to later on that evening I was eating chicken soup and i spilled some on the laptop mouse pad.
After I cleaned everything up I noticed my laptop was turned off. I go to turn it on and it shuts off after a few seconds. At this point I bust out the phillips and start taking it apart and let a small fan air it out for a few hours. When I put it back together I noticed it was still doing the same thing but *ONLY* when the power cord was connected and it wasnt charging when off (charging led on laptop wasnt turning on).
After cursing a bit I decided to take the entire thing apart and noticed the stain on the motherboard from the chicken soup. I cleaned it with rubbing alcohol and put it back together one more time. At this point the computer powers up and runs with the power cord connected but still doesnt charge. I checked the charging connector when it was taken apart and everything looked good. (didnt notice any cut wires or soldering issues) At this point I went and started checking the power cord with a voltmeter and the converter/cord is working (19.4Volts are coming at end).
Decided to go to frys today and check out power cords anyway and even with a new one it still wont charge. Its obviously not a battery or power cord issue. I think its the motherboard but Im unsure of how to test the charging circuit on a motherboard or even if its something I can fix. Can anyone shed some light for me on this? I dont really want to spend 400-500$ on a new motherboard if its something I can fix by myself for a lot less.
As always any help or input is greatly appreciated.
Cliffs: Laptop busto!!!!
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Have you checked the metal for a charge not only on the AC charger but the physical laptop? Could be something slightly loose. Another thing you can do is to use 99% alcohol and pretty much wipe down everything, let it dry out in a dust free area and see if it works. If that doesnt work theres a few other things we can look into doing..
Thread Starter
previously known as wrxBRAH
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From: San Jose / Campbell
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Have you checked the metal for a charge not only on the AC charger but the physical laptop? Could be something slightly loose. Another thing you can do is to use 99% alcohol and pretty much wipe down everything, let it dry out in a dust free area and see if it works. If that doesnt work theres a few other things we can look into doing..
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If I'm understanding correctly, you're asking me if I checked for voltage drop or short on the laptop side of the connector correct? If so I only visually checked it but I can test it tommorow with power going to it to make sure there is voltage on the laptop side. I'll also rub down the rest of motherboard with isopropyl alcohol. I only have 97% on hand. That should do the job correct?
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97% should do the job. Do you have an icon on the screen that shows whether your computer is on battery or outlet power? See what it says if you do have it (roll the pointer over it) while the cord is plugged in and not plugged in and see if the state changes. While on cord power, does your computer die after a few hours of use as it would on battery? If not, the charging circuit could have been affected by the spill. Most laptop adapters put out enough amps to kill circuits when shorted. They need to put out the amps to not only charge the battery, but run the laptop at the same time. For example, my adapter puts out 19.4vdc with a max amp output of 9.5A.
its the motherboard. get it replaced if its under warranty.
i work the dell laptops and had a few of them do the same thing where it would not charge and turn off the power adapters. although we never hear how it was done. we just replace the motherboard and issue was fixed.
i work the dell laptops and had a few of them do the same thing where it would not charge and turn off the power adapters. although we never hear how it was done. we just replace the motherboard and issue was fixed.
Thread Starter
previously known as wrxBRAH
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From: San Jose / Campbell
Car Info: 2004 FXT
97% should do the job. Do you have an icon on the screen that shows whether your computer is on battery or outlet power? See what it says if you do have it (roll the pointer over it) while the cord is plugged in and not plugged in and see if the state changes. While on cord power, does your computer die after a few hours of use as it would on battery? If not, the charging circuit could have been affected by the spill. Most laptop adapters put out enough amps to kill circuits when shorted. They need to put out the amps to not only charge the battery, but run the laptop at the same time. For example, my adapter puts out 19.4vdc with a max amp output of 9.5A.
86fh6.jpg at Free Image Hosting
*no idea why these pics wont load with image tags
its the motherboard. get it replaced if its under warranty.
i work the dell laptops and had a few of them do the same thing where it would not charge and turn off the power adapters. although we never hear how it was done. we just replace the motherboard and issue was fixed.
i work the dell laptops and had a few of them do the same thing where it would not charge and turn off the power adapters. although we never hear how it was done. we just replace the motherboard and issue was fixed.
Acer Aspire 5742G-6600
Last edited by FXTbrah; Apr 11, 2013 at 11:27 AM.
Thread Starter
previously known as wrxBRAH
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Laptops run without the battery as long as the charger is connected to the wall. Mine doesnt anymore. I believe that rules out a battery problem.
Sorry if I didnt make that clear in the initial post.
Sorry if I didnt make that clear in the initial post.
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Here are a few suggestions:
1) check there are no shorts on the power adapter receptacle (laptop side)
2) Check voltage at receptacle when you plug the power adapter (with no battery) and turn it on.
3) There's a section, to the right of the circled area, that looks covered with foam. Can you remove it and take a picture (if possible with higher resolution).
4) can you take a higher resolution picture of circled area?
5) There's a diode (the orange component with black marking which annotates the cathode). Measure it's integrity with the meter. it should give you a readout of ~0.6V.
6) you can check the continuity/resistance on each of the passive components (black ones are resistors, the beige are caps usually)
It's obviously not a battery problem, but the power section in your laptop. Just looking at the pics, there are no obvious burned traces and components (although there's a covered section). ICs can fail really quick with no visual indication. Can you make out the writing on the IC maybe?
EDIT: When you check continuity/resistance, do it with battery out and adapter disconnected
1) check there are no shorts on the power adapter receptacle (laptop side)
2) Check voltage at receptacle when you plug the power adapter (with no battery) and turn it on.
3) There's a section, to the right of the circled area, that looks covered with foam. Can you remove it and take a picture (if possible with higher resolution).
4) can you take a higher resolution picture of circled area?
5) There's a diode (the orange component with black marking which annotates the cathode). Measure it's integrity with the meter. it should give you a readout of ~0.6V.
6) you can check the continuity/resistance on each of the passive components (black ones are resistors, the beige are caps usually)
It's obviously not a battery problem, but the power section in your laptop. Just looking at the pics, there are no obvious burned traces and components (although there's a covered section). ICs can fail really quick with no visual indication. Can you make out the writing on the IC maybe?
EDIT: When you check continuity/resistance, do it with battery out and adapter disconnected
Last edited by guitar_player; Apr 11, 2013 at 02:53 PM.
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I'll have to look at home and see the pictures and tell you further what to do. It shouldn't be a battery problem and more likely it is contact issues.
Thread Starter
previously known as wrxBRAH
iTrader: (17)
Joined: Sep 2010
Posts: 3,383
From: San Jose / Campbell
Car Info: 2004 FXT
Here are a few suggestions:
1) check there are no shorts on the power adapter receptacle (laptop side)
19.4 volts coming out of the laptop side of the power adapter
2) Check voltage at receptacle when you plug the power adapter (with no battery) and turn it on.
It won't turn on when just connected to power adapter but checked power on the two red and black wires that plug into the motherboard and there is 19.4 volts there as well (should rule out the plug/wire all the way to motherboard)
3) There's a section, to the right of the circled area, that looks covered with foam. Can you remove it and take a picture (if possible with higher resolution).
Cant really get a higher resolution picture as all I have is this potato phone. Took the fabric off and there were no issues. Everything under looked clean and no burned circuits
4) can you take a higher resolution picture of circled area?
Can't potato phone, zoomed in picture on paint and re attached at bottom
5) There's a diode (the orange component with black marking which annotates the cathode). Measure it's integrity with the meter. it should give you a readout of ~0.6V.
It didnt give any voltage reading at all when connected to power. When i checked resistance, it gives 10k ohms.
6) you can check the continuity/resistance on each of the passive components (black ones are resistors, the beige are caps usually)
It's obviously not a battery problem, but the power section in your laptop. Just looking at the pics, there are no obvious burned traces and components (although there's a covered section). ICs can fail really quick with no visual indication. Can you make out the writing on the IC maybe?
EDIT: When you check continuity/resistance, do it with battery out and adapter disconnectedYep yep ofcourse
1) check there are no shorts on the power adapter receptacle (laptop side)
19.4 volts coming out of the laptop side of the power adapter
2) Check voltage at receptacle when you plug the power adapter (with no battery) and turn it on.
It won't turn on when just connected to power adapter but checked power on the two red and black wires that plug into the motherboard and there is 19.4 volts there as well (should rule out the plug/wire all the way to motherboard)
3) There's a section, to the right of the circled area, that looks covered with foam. Can you remove it and take a picture (if possible with higher resolution).
Cant really get a higher resolution picture as all I have is this potato phone. Took the fabric off and there were no issues. Everything under looked clean and no burned circuits
4) can you take a higher resolution picture of circled area?
Can't potato phone, zoomed in picture on paint and re attached at bottom
5) There's a diode (the orange component with black marking which annotates the cathode). Measure it's integrity with the meter. it should give you a readout of ~0.6V.
It didnt give any voltage reading at all when connected to power. When i checked resistance, it gives 10k ohms.
6) you can check the continuity/resistance on each of the passive components (black ones are resistors, the beige are caps usually)
It's obviously not a battery problem, but the power section in your laptop. Just looking at the pics, there are no obvious burned traces and components (although there's a covered section). ICs can fail really quick with no visual indication. Can you make out the writing on the IC maybe?
EDIT: When you check continuity/resistance, do it with battery out and adapter disconnectedYep yep ofcourse
Bolded are answers and what I checked.
Last edited by FXTbrah; Apr 11, 2013 at 09:51 PM.
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From: Fremont, CA
Car Info: 2010 WRX 5dr
Hmm.. So that section is by the mouse pad /buttons, which is away from the power connector. Highly doubt the power section would be in the opposite end of the input power receptacle, but one of the other regulators might have been shorted. That part you took a pic (good pic btw) is a "comparator" (LM393), which is a simple circuit (there are 2 circuits on that IC) that outputs a "high" or "low" based on whether the (+) input is at a higher or lower potential than the (-) input.
Check the voltage, with the adapter on, between pin 8 (top right most) and pin 4(botton left most).
Check the voltage, with the adapter on, between pin 8 (top right most) and pin 4(botton left most).