# Laptop suddenly losing power (while plugged in)



## Azuses (Mar 23, 2014)

For the second time in three days my Asus Laptop, while plugged into mains power, has suddenly shut down. It's as though someone has held the power button (or if it were a desktop, turned it off at the mains).

I have absolutely no idea what caused this (today I was copying some files and browsing the web, the other day I was listening to music). I'm not sure how to use the event viewer but perhaps that might have some clues? Could anyone point me in the right direction at being able to solve this? 

Thank you 

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: Intel(R) Core(TM) i3-3217U CPU @ 1.80GHz, Intel64 Family 6 Model 58 Stepping 9
Processor Count: 4
RAM: 3981 Mb
Graphics Card: Intel(R) HD Graphics 4000, -2041 Mb
Hard Drives: C: Total - 454969 MB, Free - 12483 MB; E: Total - 953634 MB, Free - 310992 MB;
Motherboard: ASUSTeK COMPUTER INC., S400CA
Antivirus: avast! Antivirus, Updated and Enabled


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## Tabvla (Apr 10, 2006)

It might be helpful if you tried to determine if this problem is due to a Hardware or Software issue.

Check on the following to see if it is a Hardware problem


When the laptop is plugged into the Mains does the charger get warm?
Is the laptop, when plugged in, running at normal, below normal, above normal temperature?
Are the cables in good condition?
Does the charger plug sit firmly in the laptop socket?
Is the charger LED on the laptop ON when the charger is charging?
When the charger is plugged in is the screen brighter or the same as when the charger is plugged out?

T.


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## Azuses (Mar 23, 2014)

Hi mate,
Thanks for the questions - see my responses below but all in all i don't think it's a battery or charger problem:


The charging block is generating some heat and is sightly warm.
The laptop feels to me to be running at a normal temperature. The bottom of it is warm (though like the charger, not hot).
Cables look to be in good condition, and are fully plugged in.
The battery has a green led indicating it is fully charged.
Unplugging the laptop makes the screen go dimmer.


I mentioned the fact it was plugged in more to rule out the fact it could have died from low battery. It was fully charged and hasn't been running on battery since last week, but it was such a sudden failure (no warnings or error messages) that intuitively it felt hardware related. Very odd!


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## Tabvla (Apr 10, 2006)

Seems like the charger is doing its job.

The next piece of Hardware is the battery.


Is the battery running at normal temperature?
Is the battery seated securely in its enclosure?
Are the battery connectors clean?
What happens if (with the laptop ON) you open the battery enclosure and push gently on the battery in several directions?

T.


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## Azuses (Mar 23, 2014)

The design of my laptop is that you have to unscrew the entire bottom panel to get to the battery. I've never done this before but can do so if you'd like. It looks like this - http://www.laptopultra.com/guide/asus-vivobook-s400ca-disassembly/

From feeling the bottom it seems to be running at a normal temperature (warm but not excessive). I would suspect the connectors are clean given the sealed nature of it but check the rest without taking the panel off - should I leave it on or try it?


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## Tabvla (Apr 10, 2006)

No, I would not investigate the battery any further at this stage.

Let us assume for the moment that it is not a Hardware issue but rather a Software issue.

The first place to look would be the Power Settings in Windows. What are the Power Settings? Is the Laptop programmed to Shutdown or go into Sleep Mode or is the Hard Disk programmed to stop or the Monitor programmed to Sleep....?

T.


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## Azuses (Mar 23, 2014)

The display is set to turn off after 20 mins on battery and the laptop set to sleep after 1 hour on battery. When plugged in, it's "never" for both.

The HDD is set to sleep after 20 mins on both battery and power. (Is this normal? Should the HDD be going to sleep? I've never noticed it do anything after 20 mins activity but not sure what there'd be to notice).


I left my laptop on overnight and during today, I came back and it was still on, so no loss of power. Both times it's done this it was while I was actively using it, there hadn't been any period of inactivity. I should also point out it was a complete shutdown rather than going to sleep, as it went through the full start up procedure rather than turning instantly on to the windows login screen.


I found in the event viewer an entry for 6:01pm yesterday, when it turned itself off. It's quite generic but may make more sense to you than me!

"The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly." Task category 63, event id 41. - unfortunately no explanation for why.

The same entry is there for 30th Jan, when it did it again (the first time I noticed). There was also one on the 18th Jan, 20th december, start of november and a couple before then, though I don't recall what these were. I presume this log is created for any loss of power, which could include times I've deliberately held the power button. Yesterday and 30th Jan are the only times I remember the laptop switching itself off in an instant with no warning!


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## Tabvla (Apr 10, 2006)

> The display is set to turn off after 20 mins on battery and the laptop set to sleep after 1 hour on battery. When plugged in, it's "never" for both.


This is not related to your problem.... but those are rather long times. On battery 10min for display and 20min for laptop and on mains power 20min for display and 30min for laptop are usually adequate for most purposes.



> The HDD is set to sleep after 20 mins on both battery and power. (Is this normal? Should the HDD be going to sleep? I've never noticed it do anything after 20 mins activity but not sure what there'd be to notice).


Many HDD manufactures now recommend that there is no benefit to shutting down the HDD. In any case in a laptop environment the HDD will sleep when the laptop sleeps.



> I left my laptop on overnight and during today, I came back and it was still on, so no loss of power. Both times it's done this it was while I was actively using it, there hadn't been any period of inactivity. I should also point out it was a complete shutdown rather than going to sleep, as it went through the full start up procedure rather than turning instantly on to the windows login screen.


Now that sounds like a Hardware problem.



> I found in the event viewer an entry for 6:01pm yesterday, when it turned itself off. It's quite generic but may make more sense to you than me!
> 
> "The system has rebooted without cleanly shutting down first. This error could be caused if the system stopped responding, crashed, or lost power unexpectedly." Task category 63, event id 41. - unfortunately no explanation for why.


Every time that I have seen "...Task category 63, event id 41..." the problem has been related to the power supply unit. I am not saying that this is necessarily the problem with your laptop, but simply that I have not seen this error related to any other source.

And that makes sense because if Windows detected a PSU problem the immediate response would be to cut the power to the unit so as to prevent any permanent damage from over-voltage or similar PSU issues.

If the laptop is still under warranty then I would strongly recommend that you take it back for repair. If it is out of warranty then you will need to monitor things very carefully. From a safety perspective it would probably be a good idea to Shutdown the laptop and unplug it from the Mains power at night or if you will be away from it for an extended period of time, until you have correctly identified the source of the problem.

Laptop batteries have been known to catch fire or even explode. And laptop PSU's are sometimes not always of the best quality. It may be an over-reaction, but it is always preferable to err on the side of caution rather than be faced with some major disaster - like your house burning down or personal injury.

T.


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## Azuses (Mar 23, 2014)

Thanks - Unfortunately the laptop is out of warranty. What you have said is concerning though - would ordering a new charger be a good thing to do then?


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## Tabvla (Apr 10, 2006)

Azuses said:


> Thanks - Unfortunately the laptop is out of warranty. What you have said is concerning though - would ordering a new charger be a good thing to do then?


No, not necessarily. Without access to some basic electronics test equipment it is (almost) impossible to accurately determine where an electrical problem exists.

Heat and smell are usually the first indicators that something is not good. But by that time it might already be too late.

However, there is one piece of non-technical mains-electricity equipment that can often give one an early indicator that there could be a problem - or not as the case may be. And that piece of equipment is an Electricity Cost and Usage Indicator, which costs about US$15.

One of the readings on such a meter is Watts. Now Watts = Volts x Amps. For mains electricity you should already know the Volts and if you now know the Watts then you can calculate the Amps. Knowing the Amps can tell you a lot about the health of any piece of mains-connected equipment.

For example, if a piece of equipment is supposed to draw a maximum of 5 amps and your calculation shows that it is drawing the max or over the max then that to me would indicate that the equipment might be suspect.

T.


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## golddust (Jan 2, 2005)

You can find out if your battery is charged/charging or if your laptop is running on the battery or A/C. A little app called Battery Bar is available. I have it on my laptop. The free version should give you all the info you need .https://batterybarpro.com/basic.php . Once installed, an icon will appear in your taskbar notification area. It will tell you if you are running on A/C or using your battery. Hold your mouse over the icon and a bubble pops up with additional info.


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