This laptop has a power problem. The battery stops charging when I move the power cord on the DC adapter. When I start moving the cord left to right, the power LED light on the front goes on and off and the battery charge LED goes on and off too.
I removed the battery and tested the laptop again. The laptop starts fine from the DC adapter when the battery is removed, but as soon as I start moving the power cord the laptop shuts off. It looks like the laptop looses power immediately.
If you have a problem like that, most likely it’s related either to the power adapter or the DC-IN power jack.
First of all, I tested the power adapter with a multimeter. The power didn’t cut off no matter how badly I moved the cord. The power adapter output voltage was 15.45VDC all the time. That means there is nothing wrong with the power adapter and most likely there is a problem with with the power socket inside the laptop.
By the way, I just purchased a brand new FLUKE 179 multimeter here for less then $160. The retail price at Sears for the same multimeter is $240. FLUKE is a really good brand. Just a side note.
Now I’m going to test the power socket inside the laptop.
In order to access the power socket I had to disassemble the laptop and remove the top cover assembly with the display.
You can find disassembly instructions for many HP, Dell, IBM, Lenovo, Sony and Toshiba laptops in these service manuals and guides.
In the laptop I was fixing (Tecra M2) the power jack is attached to a DC-IN harness and this harness can be unplugged from the motherboard.
As you see, I removed the DC-IN harness from the motherboard, plugged in the power adapter and tested continuity with my multimeter as it shown on the picture.
When the power cord is still, the voltage output is 15.45VDC, the same as on the plug.
But as soon as I start wiggling the plug inside the jack, the power cuts off and voltage goes to 0. It means, the power harness is bad.
The problem was fixed after I replaced the defective DC-IN harness with a new one.
In some laptops the power socket (DC jack) is soldered to the motherboard.
If the battery stops charging when you wiggle the power plug inside the jack, either you have a bad power adapter (test it with a voltmeter) or the power jack is broken or loose.
You cannot simply unplug the jack and replace it with another one. You’ll have to unsolder the old jack and solder a new one back on the motherboard as I described in this post.
If the power jack is not broken but loose (not making good contact with the motherboard) you can resolder the old jack without replacing it with a new one.
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November 26th, 2010 at 6:50 am
Hi,
I’m so sorry for asking a question on an old post, but after hours of research this site seems the only one to really know their stuff.
I have a two year old toshiba laptop. I’ve used it A LOT. After I lost my 1st charger, I bought a generic one. I lost that one too. The thing is after my second one all my other chargers (my current one is my 5th one) stop working after 2 months!!! Now I started getting a “Consider replacing your battery” from Windows 7.
My question is: Is this an internal hardware problem? is this a battery problem? only a charger problem? or what? … I’m just very confused because I have no idea what to do and I don’t know if it’s smart to invest in another battery just to see another charger last for only 2 months.
Really appreciate the help!
October 23rd, 2010 at 9:21 pm
Greg,
If you have the latest BIOS installed, most likely reflahsing the BIOS will not help.
If the laptop runs fine from AC adapter with battery removed, most likely the AC adapter operates properly.
I think it’s either bad battery (more likely) OR possible motherboard failure (less likely).
I think replacing the battery is your best bet.
October 19th, 2010 at 5:21 am
I have an Inspiron 6400, original 65W adapter and on second battery 6-cell which I’ve been using for a little less than a year.
It is stuck at charging at 7%. It was stuck at 12%, but in trying many fixes, I ran on battery only for a while which decreased the charge in it.
The bios recognizes and identifies the AC adapter and the battery. The bios and Dell Quickset state the battery is operating normally, but the charge does not increase.
Only one 1/2 lights come on when I press the battery button.
I have reset the bios to factory defaults, and tried other tricks mentioned in the Dell forums, i.e. jiggling wires, holding power button down, disconnecting power and battery in different order then rebooting, doing the same after removing ACPI battery from device manager.
I have not reinstalled the BIOS. I am already running the latest A17 BIOS.
I did not automatically purchase a new battery or ac adapter yet, because supposedly, they are functioning ‘normally’?
What should I do next?
Reinstall the A17 BIOS?
Buy a new battery?
Buy a new AC charger adapter?
Something else?
September 27th, 2010 at 3:30 am
Sierra,
It depends what laptop you have.
In some laptops the jack is soldered directly to the motherboard, in other models it’s attached to a harness.
What is your laptop model?
September 16th, 2010 at 8:37 am
If the pin of the DC-IN power jack came out, what should I do?
1. replace the power jack?
2. resolder the pin into the power jack? How can I do that?
Thanks a lot!
August 29th, 2010 at 1:28 pm
T,
How it flashing? Is it switching from AC power to battery power and because of that screen changes brightness?
If you think your problem related to the AC adapter, next time make sure to buy the original factory replacement, not just a compatible third party adapter.
August 27th, 2010 at 4:43 pm
How do i get my laptop screen to stop flashing?? i changed the adaptor 3 times and the replacement one works fine for like 3 months and then it starts to flicker again?? and the wire connected to the laptop gets really hot as well?? please help!!
August 15th, 2010 at 9:07 am
john,
Dead charger? I guess you’ll have to buy a new one. Laptop chargers not designed for repair.
August 15th, 2010 at 4:05 am
My charger is dead how to fix this mess
June 11th, 2010 at 4:40 am
If I bring my computer to be fixed, about how much will a fix like this cost? Is it worth fixing a 3 year old laptop, or should I invest in a new one?