General discussion

Laptop power cable/jack problem.

Alright so i'm not normally one to go net-hunting for solutions to my problems, i'm a fairly competent techy and have repaired many strange and unusual problems. But this has me stumped. I just resoldered a powerjack into a Fujitsu Siemens Lifebook (old i know) for a friend. It works fine while the laptop is off. It will charge the battery, you can see the indicator on the little lcd panel filling up the battery as if it is charging. However 9 times out of 10 when I turn on the laptop it will stop charging and run entirely off the battery.

So:
Plugged in, no battery = indicates its plugged in until i press the power button and the lcd panel goes blank as if i pulled the wire out.

Plugged in, with battery = indicates that its plugged in and charging, until I press the button then the 'plugged in' and 'charging' symbols disappear and the battery rapidly drains.

Unplugged, with battery (obv) = Laptop turns on, works fine, but battery rapidly drains.

So i know that it needs a new battery but my friend isnt bothered about it being portable, he just wants it to work when its plugged in. On occasion it will recognise that its plugged in and does charge the battery when its turned on. I'm thinking either faulty connection inside the jack itself for the signal wire or faulty connection to signal wire in the power lead. What do you guys think? Anyone had a similar problem? I do not want to replace anything, I would much rather repair whats already here as he doesn't need it to be portable, just to work. I have repaired chargers and dodgey problems with powering before and am competent with soldering and multimeter testing but I can't seem to get my head around this...

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Comments
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How old is that battery.

Given the SLIM details about make, model and AGE it could be another 300 CYCLE battery that is over 18 months old and nothing is wrong except it needs a new battery.

Tell more.
Bob

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battery IS broken, but DO NOT need the battery.

I apologise for the limited details about the laptop and age, it is an old laptop. The battery DOES need replacing but this he can do at a later date. The problem I am asking for help with is NOT the battery though, it is something else, either power board on laptop itself or the charger. If it was just the battery causing the issue then when I remove the battery and plug it in, the laptop would turn on powered entirely by the charger. However the issue is the same whether the battery is in the laptop or not. Like I previously stated, when the battery is in, the laptop will work fine it just wont recognise that its plugged in when it is turned on. When its turned off it not only recognises that it is plugged in, but also charges the battery. I think its the signal wire in the charger or the point it connects to on the jack. Please, no more posts about the battery, to an extent that is fine it still charges to 100% it just drains relatively quickly.

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Reading your post again.

You wrote about the ______ so many times it was hard to avoid a reply that asked about it.

I see nothing wrong with this behavior. That is, given the age and _____ condition. If this was mine I'd yank the _______ and if it didn't power up get out the Volt meter and see if power is making to the power jack and beyond. It's basic electronic troubleshooting skills but once in a while folk want a course in the basics but that does not fit here.

For those, you have to tell them to touch up the solder work and again, if they need a course in soldering it does not fit here. At that point you have to go with the following advice. Replace the cheapest parts first.
Bob

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Lol

It's not a normal thing for the charge to work perfectly when the laptop is off but not when it's on. And I am not looking for a course on the basics I am simply trying to see if anyone has had the same problem and what they did to repair it. Even the best techys need to ask advice from time to time and if anyone disagrees with that then they are obviously not a very knowledgable person haha. As to the multimeter and solding comments I have just stripped it down, the soldering is fine and I am currently testing circuits, I started all this right after posting on here I just thought it might save time and effort if someone had the same problem and knew what it was. Also i've never really experienced a faulty signal wire so I am kind of unsure what problems that would cause, so I was looking for someone to either confirm that it could be that or explain why it isn't. But I have to apologise for the confusion over the battery, I attempted to make it clear that I knew the battery was on its way out, but at the same time that this was NOT the problem and obviously by doing this I just caused the confusion lol. Thanks for the replies though Happy

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I've seen this for many reasons.

Mostly about the age of the machine and the hit the charger and circuits take when the _____ was failing. You are also over the expected life span of some basic parts in the laptop and charger. Since it's not the ______ you would inspect all the electrolytic capacitors (see BAD CAPS on google for what to look for) and while in there touch up any suspect solder joints.

The charger at this age can be gone as well. Your choice to try another or open it for the same inspection and touch ups.
Bob

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hmm

Ooooo I think I just had a breakthrough! While I attempt to repair this does anyone think that a wobbley signal port thing on the powerjack could be causing my problem? :-s

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hmm

like, super wobbley... As in, I think it might be getting pushed to one side by the pin for the signal wire when im inserting the power cable. That would explain why as soon as I turn it on it decides it doesn't like the charger no more...

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yup...

ok so yea that was the problem aparently the center peice of the powerjack was wobbley it had broke away from part that connects it to the board thats what was causing the problem... solution, new power jack cba to pull this one to bits just for a temporary repair...

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Google this

Laptop Power Jack Repair.

It's a big (small) business.

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