Won't charge when low on charge

[linkrulesx10]

Heya All

Back Ground

I have a Toshiba P100 Laptop, that also has a few other things wrong with it including sporadic green and red pixels that are not screen or graphics card related. *as both have been tested/replaced* Included inase it was relavent

Now this has been going on for a while, finally starting annoying me enough to do something about it.

Problem

My laptop's battery works when off charge.
However if I get it down low like 20%, 50% something below around 80-90% *dont have exact numbers for this* the problem occurs.

I will plug the charger in and it will start charging.
After some amount of time later, 3 seconds, 5 minutes, half an hour it will stop charging. Jiggling it may or may not have an effect on this I have been unable to determine whether it plays a role.
When you plug it out and in again it once again starts charging.

While it is not charging it is also not using up the battery so the battery will stay constantly at whatever percent it is at. Also the computer then lags every few seconds like clock work, it is momentary lapse. Where it just doesnt take input or do what it is supposed to be doing making typing things annoying as you often miss letters.

Additional Information

Note this problem doesnt occur when the laptop has alot of charge. Only when it is low.

If it matters my laptop connecter is 4 pronged, which always struck me as odd considering most laptops used circular plug ins.

What sort of problem am I looking at here? Circuitry, faulty battery?
I have searched and browsed these forums and other places and have been unable to find problems quite like this.

Thanks for reading I appreciate it!

[techsheaven]

The most common issue with charging is the socket where your power adapter plugs in. Power down the system and remove the battery. While a plug in it's socket may or may not be loose, that is NOT what we are looking for. Apply a small amount of pressure to the socket to see if it is loose. Often, the solder will break an simply needs to be re-soldered. Sometimes the socket itself is broken (I suspect this is the case with yours); the part will cost only a few bucks, but taking the machine apart may take hours.

If the socket seems solid, leave the battery out, connect the power cord and boot the system -- Tell us what you find out!

[techsheaven]

Hold the phone. After I shot off my mouth, I was going to look up some links for you. I found out that your jack is not soldered in, but plugs in! I t may be loose inside!

Is this yours? http://www.laptopjacks.com/view_part/Toshiba-P100-ST9762-Laptop-DC-Power-Jack-TS422500.html

Though it's more expensive than others (about $30US) it requires no soldering.

[linkrulesx10]

Ok thanks.

I do have two questions, what do I do once I remove the battery?

The socket seems pretty firm in my computer.

Another question how could this socket explain this problem only really happening when low on charge?

Thanks for your help :)

[techsheaven]

Good question.

I have seen power jacks do strange things. Most of the time, someone calls and says, "My kid tripped over my power cord and now I have to put tape and a rubber band on it to make it work." This is the classic power jack failure.

Anther time, someone asked me to look and her laptop because it would run on the power cord but the battery would not charge, nor would the indicator light come on. She bought a new battery and it would not charge either. She charged the batteries in a friends computer and it would run on them! I took it apart and noticed the solder was cracked. one touch with a soldering iron fixed it.

In your case, I think the connector may be barely on, so high amperage can not pass (as when the battery is low and drawing more) but low amperage can. If I'm right the battery is acting as a buffer for the fluctuating power. If you run the machine without the battery, and it seems to run fine, but suddenly shuts down, it may be that. It could be other things, but I go to the most likely component.

The military uses this approach with the idea that it is better to have an aircraft with a probable fix rather than no fix. We are on step one of what could be many.

[denaeva]

Have you used the laptop battery for more than one year?
If that's true, you maybe replace your battery or adapter
Is this 120W Universal AC Adapter for Laptop suitable for your?

[linkrulesx10]

Thanks Techeaven, I will take it out and see how it goes without the battery.

Another thing that may be important as after more testing I worked out it charges 100% when the laptop is turned off. Once again this could be explained by your low amperage explanation. Anyway thanks and back to testing :)

Also Denaeva I have already replaced my laptop AC adaptor because I initially thought it might be the problem but the problem occurs on both.

Well my battery is out and my computer seems to be good and not having those annoying stutters it normally does. Once again it could be the voltage thing, maybe the battery is the fault. I am sensing I may have to see a technician who can look it this better then I can if I can't issolate the problem...

[linkrulesx10]

Double Post due to restart and firefox auto save settings.

[techsheaven]

Charge the battery as much as you can and then see if it holds a charge out of the laptop for about 6 hours. Battery cells can short out in such a way that they draw more amps than the converter ( power adapter ) can produce.

If you return the battery to the laptop and it is substantially lower than when you took it out - it IS the battery.

Let us know what you find out. I know we have not discussed your video issue yet!

[linkrulesx10]

I had the battery out since my last post just put it back in and same charge that I left it at.

So unfortunently we can't point the finger at the battery yet.

If it is not hte battery the alternative would mean it would be like the powerboard in the laptop that is causing the problem? I can get the DC power plug for 10$ here in australia so I may go see if that can fix the issue as well. *At least I think it is 10$ stupid website has no pictures have to find out more info...*

Well I just talked to my Apprentice technician friend he reckons it would be the power supply, most likely intergrated into the mother board and if it is that then well I guess I am screwed to try and repair it.

Thanks for all your help, I appreciate it alot. And if you have any more ideas I would be happy to follow through with them.

[techsheaven]

If you replace your power plug, make sure it has the same output voltage and at least the same amperage as the original equipment. Didn't you say you already replaced it?

If it gets down to your motherboard, pay close attention, as you diesassemble the laptop, to connectors. I have repaired many laptops by simply re-seating loose connections (I suspect this may be the issue with your video too).

I want to key-in on a symptom you mentioned in passing, "those annoying stutters." This sounds like a symptom of a bad power jack... Will you tell me mor about "those annoying stutters?"

[linkrulesx10]

I will gladly tell you more.

These stutters only occur when it is not charging.

It seems like clockwork, for a brief moment it will not accept inputs and the screen will freeze but it is like 0.3 of a second *not exact just an estimate* and it happens continously untill it starts charging again.

[techsheaven]

It sounds to me like the system is switching power profiles. I know you said you have replaced the power cord, so I shouldn't have to ask if there is physical damage to it (cuts, bumps, twists, etc.). That puts us right back to the power jack. Are there bent, broken, or corroded pins? There should be strong contact between connections. What abou the wall outlet? Is it tight when you plug in?

Is there a light in the power "brick?" When the laptop stops charging is the light on or off?

[linkrulesx10]

there is no light on the power brick so I dunno how that goes.

My laptop has a yellow charging light that flickes off when it is not charging and on when it is.

Well I have not yet had the ability to take my laptop apart and look at but eexternally i cant see any problem. I just noticed smeething that maybe of importacne there is a chip in the casing near the power jack... Maybe that coulod have damaged it. Better look into that as well.

[techsheaven]

http://www.eserviceinfo.com/downloadsm/37636/Toshiba_Satellite.html

Try the link above. Scroll down to:

Download >> To download the file, please, click here ! << Download

Is this your Laptop Service manual? It has some great troubleshooting flow charts and disassembly instructions.

[linkrulesx10]

oooh it is, had no idea somethign like that existed. Thanks will be sure to check it out.

[linkrulesx10]

Thanks for your help, it has helped me narrow things down. I do believe the problem is a faulty mother board which is out of my price range to repair.

I had this verified today by talking to a toshiba technician who said it would be the motherboard.