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Cutting open my laptop to try and fix the power supply? Watch

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    I have an old Acer laptop I got through my dad because he worked in education and could get them cheap.

    Recently I had a problem with the power lead, and the power input. Its now got to the point where I cant get any power and the battery has died, so its useless really.

    I think the issue is with the power input because it wobbles when you push anything into it.

    Iv tried taking off the back of the laptop but the casing seems to be welded shut around the power supply. I can see the power input inside because its yellow and stands out. Iv heard that nobody can repair the power supply in a laptop because its too hard, but Im thinking of cutting the casing off myself with a saw/drill and then trying to superglue the power input back into place.

    Is this a good idea and might it work, or is there no hope for the laptop and I should buy a new one?
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    Sounds like something that you probably don't want to do. If you can somehow superglue the power supply without taking the casing off, like using an old paintbrush to put glue around the outside, then that would probably be better.

    Are you sure it's not the battery that has stopped working? They are quite expensive to replace so unless you think the computer is going to last you a good year or so you probably don't want to do that.

    If there's no other way, you could try hacking off the back of the case, but you don't know whether that will damage it further. Either way, if it's totally not working anyway, it would probably be worth doing!

    Try google as well, people on the internet seem to know everything, and you might be able to find how to hack the back off the best way!
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    (Original post by lamyers1)
    Sounds like something that you probably don't want to do. If you can somehow superglue the power supply without taking the casing off, like using an old paintbrush to put glue around the outside, then that would probably be better.

    Are you sure it's not the battery that has stopped working? They are quite expensive to replace so unless you think the computer is going to last you a good year or so you probably don't want to do that.

    If there's no other way, you could try hacking off the back of the case, but you don't know whether that will damage it further. Either way, if it's totally not working anyway, it would probably be worth doing!

    Try google as well, people on the internet seem to know everything, and you might be able to find how to hack the back off the best way!

    Iv tried replacing the battery already its not that - and iv replaced the end of the power lead too, i don't think its that. The battery works ok considering it was second hand but without the power its ended up just powering down whilst i spent hours fiddling and twisting the lead to try and find a position where it bites.

    Thanks for your help, iv posted this on a couple of sites too - Il try and put a picture up later
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    (Original post by Clez)
    I have an old Acer laptop I got through my dad because he worked in education and could get them cheap.

    Recently I had a problem with the power lead, and the power input. Its now got to the point where I cant get any power and the battery has died, so its useless really.

    I think the issue is with the power input because it wobbles when you push anything into it.

    Iv tried taking off the back of the laptop but the casing seems to be welded shut around the power supply. I can see the power input inside because its yellow and stands out. Iv heard that nobody can repair the power supply in a laptop because its too hard, but Im thinking of cutting the casing off myself with a saw/drill and then trying to superglue the power input back into place.

    Is this a good idea and might it work, or is there no hope for the laptop and I should buy a new one?
    If it's welded shut I'd assume it's welded for a reason. Power supplies can electrocute you even with the power off / battery removed, unless you know what you're doing I wouldn't open it up.
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    The chances are the case will come apart. There is probably a screw or clip that you havent spotted yet. Laptop cases are notorious for needing extra care to strip. As for repairing,well do you have any test equipment,soldering equipment and skills? The power input is likely to be around 13v and the main psu will be external therefore no internal hazard
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    (Original post by goldenfish)
    If it's welded shut I'd assume it's welded for a reason. Power supplies can electrocute you even with the power off / battery removed, unless you know what you're doing I wouldn't open it up.
    I have the battery out and the power off, how would it electrocute me?

    Could I wear washing up gloves?
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    Hey, (computing student here :P)

    The thing with cutting open laptops is, they're not mean to be taken apart. They can be by professionals of course, but unlike PCs they are not meant to be able to get things swapped and such.

    What it sounds like is that it has been welded in this way to protect the power supply so that people do not break it or go into it. It can be dangerous to mess with a power supply, so I would not advise that.
    If you do want it fixed, see a computer specialist shop. They will know what to do, but it might take a lot of money to get it fixed. Try not to break into it any more, they will keep finding as much wrong with it as possible to get as much money as possible.

    Alternatively you could look online for fixing this issue. Youtube may have videos showing you how to fix it, which would be free and safe to do.

    Do not wear washing up gloves, there is still power stored in their so can be dangerous.
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    (Original post by Clez)
    I have the battery out and the power off, how would it electrocute me?

    Could I wear washing up gloves?
    Because they use electrolytic capacitors.
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    (Original post by Limpopo)
    The chances are the case will come apart. There is probably a screw or clip that you havent spotted yet. Laptop cases are notorious for needing extra care to strip. As for repairing,well do you have any test equipment,soldering equipment and skills? The power input is likely to be around 13v and the main psu will be external therefore no internal hazard
    Iv taken out all of the screws on the actual casing, there are other screws but they involve removing large pieces of hardware. I dont have any other equipment. Im very much an out of the box problem solver - someone says "oh you cant do this because you have to do that" and Im like oh **** it lets just cut the back off
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    (Original post by goldenfish)
    Because they use electrolytic capacitors.
    Messing with a PC power supply is dangerous because they use rectified and filtered AC to feed the buck converters. You get ~350VDC in a PC power supply. That is very dangerous.

    Laptop power supplies on the other hand, are fine. All the high voltage stuff is in the power brick. You only get 12V or 19V DC going into the laptop, and the laptop converts it down to all the different rails required (CPU voltage, 1.5V, 1.8V, 3.3V, 5V, 12V, etc). The only high voltage point inside a laptop is an LCD inverter, if you have a laptop with a non-LED backlit LCD. But there's no significant capacitance in there. It's almost impossible to kill yourself by messing with a laptop (I don't want to say impossible... because I'm sure there are ways if you really try).

    Do disconnect power first, though. Both AC (which is really DC) and battery.
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    I don't think fixing the power input jack is going to be difficult, if you can get to it. All you need is a soldering iron, and you can get that for £5 or something.

    Did you try looking for disassembly videos for your laptop?
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    (Original post by ihavemooedtoday)
    I don't think fixing the power input jack is going to be difficult, if you can get to it. All you need is a soldering iron, and you can get that for £5 or something.

    Did you try looking for disassembly videos for your laptop?
    Depends on how the power jack is connected to the main board. If it's soldered onto the board then some extra skill / tooling will help (I'd probably use a hot air rework station personally rather than a soldering iron). If the DC jack is connected via wires it's a much simpler job.
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    (Original post by Clez)
    Iv tried replacing the battery already its not that - and iv replaced the end of the power lead too, i don't think its that. The battery works ok considering it was second hand but without the power its ended up just powering down whilst i spent hours fiddling and twisting the lead to try and find a position where it bites.

    Thanks for your help, iv posted this on a couple of sites too - Il try and put a picture up later
    It sounds like a similar problem to what I had with my old laptop a few months ago.

    What I would recommend, take it into any PC repairs place, although not any major brand like PC World, and get them to take a look. When I did that it cost me £15 for the job, that was it, and while I probably could have done it myself I would say that for that little cash it's always worth having somebody who knows exactly what they are doing take a look.
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    (Original post by mfaxford)
    Depends on how the power jack is connected to the main board. If it's soldered onto the board then some extra skill / tooling will help (I'd probably use a hot air rework station personally rather than a soldering iron). If the DC jack is connected via wires it's a much simpler job.
    Yeah hot air is nice. I try to avoid using it though, since it always moves components that aren't supposed to be moved.

    The leads for a power jack should be pretty close together. It should be possible to just reflow them all alternatingly with an iron.

    I almost never use a hot air station now after I discovered Chip Quik a few years ago. I find it easier to remove even big high pin count SMT devices with it. Makes much less of a mess.

    In case you haven't heard about it - http://www.digikey.ca/product-detail...SMD1-ND/304148
    Best invention since sliced bread for electrical engineers.
 
 
 
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