Laptop battery stops charging when I move power cord
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.
Entry Filed under: Laptop Tips and Tricks
July 18th, 2008 at 4:41 pm
Thanks a lot, this is great stuff, but this does not solve my unique problem. I explained my problem in a comment in your previous post.
Should I even then disassemble my D610 and check the DC IN port? as when I connect the ac adapter the laptop neither charges nor discharges, and when I click on the battery icon I get : 2036:34 Hours remaining…
Can you please figure out what may be causing this?
Its not the battery as today I tested my laptop with another battery from a friends D610 and I got the same error, I also changed the charger but it did me no good.
July 20th, 2008 at 11:19 am
Faraz,
Remove the battery and start the laptop from the adapter. Wiggle the power plug a little bit. If the laptop shuts down when you move the power plug you should check the DC-IN port. If the laptop runs fine, apparently there it nothing wrong with the DC-IN port and it’s not necessary to disassemble it.
Will the battery charge when the laptop is turned off?
Here’s what you can try.
Try discharging and charging the battery. Run the laptop on the battery power until it’s empty and then charge it up.
Do you have any Dell utility for recalibrating the battery? Try recalibrating the battery.
Try reinstalling the power management software.
If it’s not the battery or the charger then most likely your problem is related to the motherboard. Apparently there is something wrong with the charging circuit.
Also, you can try reflashing the BIOS. Carefully read instructions before you reflash the BIOS.
August 7th, 2008 at 3:51 pm
My power cord was broken and I cut the wires and reconnected them again. It was working fine but then one day suddenly the laptop went off. Now my battery is not charging on my laptop. But when I put the battery on on my roomie’s laptop, I can charge it. Furthermore, If I remove the battery from my laptop and use adapter, I can’t turn my laptop on. It is able to switch on ONLY when
1) Battery is in
2) Adapter is plugged.
Even then, the battery is not charged. Nor does it get discharged. The laptop follows all the power options for my battery settings. Even the icon on right bottom shows that my laptop is running on battery and doesn’t show any DC power. But again, my battery is not getting charged, nor does it get discharged.
Now what?
August 15th, 2008 at 1:05 pm
Quick note.
When doing warranty validation, 99% of vendors will replace a defective solder joint, but will not replace a defective/damaged jack. Best way to test is by getting a pen or a paperclip and seeing if you can make the internals move around. On rare occasion, an internal will break in such a way a customer couldn’t have done it, in which case, they will cover it 80% of the time.
August 17th, 2008 at 3:21 am
Interesting-why don’t they cover the jack?I haven’t yet phoned DELL with my problem. My symptoms are if I wiggle the DC connection the laptop’s (XPS M170) internal fans come on, screen goes black and it shuts down. I have just purchased a new battery and my charger is also new.When I take out the battery and wiggle the connection it shuts down. It will not restart.It then takes a couple of hours to reboot.When I hold down the on button, with both battery and power supply in, the lights come on, it attempts to powers up, the Wifi lights come on, the Hard disc spins up, the keyboard lights up but it will not power up. When I take out the battery and the power supply and then replace them again there still is no reaction, even though I have a green battery light.Looks like it is an internal jack issue but it still charges the battery, which is different to the problem already posted. I cannot understand why the laptop will not switch over to battery even if it’s a jack problem.Also, when I first put the new battery in, it locked up and shut down after 15 minutes.This happened twice but the battery still charged. It does not seem to be an overheating problem because I clean out the fins with an air cannister regularily.