My laptop charger is f'ed up

[Gogeta70]

My laptop charger is pretty messed up. It's been this way for quite a while and i've been wondering why it happens, but never really asked, so now i'm asking.


My laptop charger is a radioshack one that has a selector switch for various voltages. The one that came with my laptop shorted out so i had to get a new one. Anyway, the radioshack one has an LED on it to indicate that it is plugged in and charging the laptop. The laptop also has a light on it (a ring around the charger plugin) to indicate that it is being charged as well.

Now, the cable that goes from my charger to my laptop has a slight short in it, so the plug that goes into the laptop has to be in a certain position while plugged in or it won't charge the laptop. If i rotate it accidentally and it stops charging the laptop, the charger itself "dies," in other words, the LED on the charger goes blank and stops charging the laptop. I then have to unplug it for a couple minutes and plug it back in to make it work again. I noticed that if the charger "dies," but is left plugged in, the charger box still remains pretty warm (almost hot enough to burn you, actually). So... what exactly causes the charger to "die"?

[bad_brain]

hmm....this sounds like some kind of fuse is triggered, most likely a varistor one (http://en.wikipedia.org/wiki/Varistor" onclick="window.open(this.href);return false;), they usually need a while to cool down until they work again, and this would explain the waiting time.
the fuse is placed in the outgoing circuit it seems, so power is still coming in and that's why the power supply still gets hot.

if you have some "weapon oil" (no idea if that's the correct term, but you know what I mean) you can apply it VERY thin onto the plug (after cleaning it) and see if this helps....this trick is often used in the highend stereo segment for connectors because it optimizes the connection quality. but make sure to really just apply a very thin film.

[floodhound2]

I will have to disagree with BB on this one. Seems to me if the charger is hot then there is a definite short and the Varistor is doing its job in this case.

We basically have 3 definitive variables in this situation

1. Charger
2. Battery
3. Laptop

1, Possibly the charging cable was shut in a bedroom door, or perhaps something has caused the conductor inside the insulation to short when a specific curve or angle is presented during charging. Inspect the cable rigorously and deduct the charger from the equation if possible. Make sure also that the power requirements are sufficient for both charger and laptop.

2, If the charger is getting real hot and the cable has no damage my next area of interest would be the battery itself. How old is the battery in the laptop? Will the laptop run with the battery removed, and if so will the charger remain hot? You should check to see if the manufacture had a recall on your laptops battery system.

3, If the battery and the charging system remain in great working order then you'll have to inspect the laptop circuit. The focal point should be the Jack that the power cable is inserted into. Loose, corroded and broke pins should be fixed.

Sure there are other issues that I have not mentioned but you can see that mainly you have to start injecting "Good" parts to find the unknown "Bad" part/s.

[Gogeta70]

I inspected the cable and aside from scuffs and scratches, there is no major damage.

The battery and laptop where both purchased in august, 2008. The battery doesn't hold much of a charge anymore (about 10 minutes of battery life at 100%), but the laptop does run without the battery. I also noticed earlier today that i had the laptop plugged in all night, but turned off. It remained charging and when i felt the box of the charger, it wasn't hot at all. So i'm not really sure what causes the charger to get hot.

Lastly, i also looked at the charger jack on the laptop itself. The pin was sturdy, and i couldn't see any corrosion on the inside of the jack either.

[floodhound2]

Did you check for Recalls on that laptop - it was common a few years ago? I think you need a new battery and as long as you are sure that the charger is sufficient. A lot of times non factory laptop chargers don't provide enough, or provide too much current / voltage. Something to think about I suppose. Hell charging a battery these days is becoming a science. But if you battery is not holding a charge time to replace it.

Here is a great battery that you might want to look into

http://www.sciencedaily.com/releases/20 ... 100455.htm

[Gogeta70]

Yeah, i forgot to mention it. I googled and checked several links, but there was no mention of recall for the battery of my laptop (hp pavillion dv6000). And it's like you said - my battery is an 18.5 volt battery, but the charger doesn't have a setting for that, so it's putting out 19 volts instead. The battery has needed replaced for quite a while, actually... It's almost pointless having a laptop that you always have to have plugged in, lol.

I checked the link you posted, but i don't think i'll be able to find a laptop battery like that...


So, do you think that replacing the battery will fix the problem that i'm having with the charger?

[floodhound2]

I would think that the charger is working. This is somewhat obvious to me because if the laptop can run while the battery is out, then the charger is working. That Voltage seems very good the only "unknown" at this point is the current.

I think that a new battery should fix this issue. But that said please don't hate on me if you buy a battery and you still have a problem. Its never a 100% certainty until you try to fix the problem.

What do you think?

[Gogeta70]

Well, i need to buy a new battery anyway. hell, even windows 7 is bugging me to buy a new battery with a message that says "Please consider replacing your battery".

Last time i checked the prices, it ran about $80 or so, so it'll probably be a while before i can afford one.

I guess no more information can really be gathered until then. Thanks for the help.

[lonewolf]

A couple of things to check the wires inside of the protective coating could have damage. You mentioned that if the cord rotates in the socket the battery quits charging. Two things that you can do to see where the problem is with the power supply.

1 if you have a dvom hook the test leads to the plug that goes into the computer. Slowly move the strain relief on the back of the plug and see if the voltage changes then work your way down the cord to the transformer watching the meter as you go. If the voltage changes anywhere as you move the cable you have found your short.

2 if you do not have a dvom leave the cable plugged into the computer and move very slowly down the cable the same as above. This will take a little longer as there is usually a short delay from when the power stops and the light goes out.

I am betting that the short will be in the strain relief at the end of the plug, that is the part where the wires are able to move the most. The cord strain relief will usually pull the insulation off the wires inside the flexible part of the strain relief so when the wires move a certain way the wires are able to short out.

Now I may be dating myself but the older power supplies used to have a circuit called a crowbar circuit. Its job depending on what it was watching voltage or current was pretty much the same. If the voltage or current went higher than specified it would activate and cause a direct short before the appliance to blow the fuse or thermal breaker thus saving the appliance. Some were wired into the main side of the supply to stop the input voltage. If you are loosing the light that tells you that it is plugged in the voltage is being broke at the input.

The other option and a much cheaper option thermal breaker on the supply transformer. A minor short in the wiring with the load of the computer could be drawing enough current to slowly heat up the transformer until the thermal breaker kicked off. If this is the case the transformer is already starting to break down the insulation between the windings and will eventually fail.

[DNR]

looks like Floodie has his neo - nice job lonewolf. You might learn a thing or two from Floodhound - our O.G. of hardware stuff that you did so nicely here.

Logical, and thorough, we need more of this.

DNR