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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May 13th, 2009 at 3:49 am
welcome
dell 1525
vista sp1
my computer is not charging or arrive at 94% and stopped
what can I do
April 17th, 2009 at 3:23 pm
Ka.Ramesh,
That could be a software related issue. Back up all personal files and try reinstalling Windows.
April 15th, 2009 at 10:01 pm
Hi,
Mine is Dell Isnpiron 6400. I updated the BIOS Version to A017. No the battery on my Inspiron 6400 was not detected anymore. I saw this on Windows Vista’s battery monitor, but also when running the BIOS setup, it said there was no battery plugged in.
The battery charges and the computer switches to using the battery when not plugged in, but I just can’t monitor its state, because even though it works, it is not detected. When running on battery, the battery indicator LED is orange. When charging it flashes green. When charged and plugged it’s off.
Thanks for any help.
March 19th, 2009 at 10:23 am
I purchased 2 AC adapters thinking that it was the problem. If only I thought to test the laptop with the multimeter.
March 5th, 2009 at 9:58 pm
i have a computer that dont charge the battery if you plug the adaptor immediately it will come up after some time if you unplug it the laptop goes off when the adaptor is on instead of showing the battery charging icon it will showing direct dc icon on the destop.my question is why all this happen and how can this be corrected i have changed battery without number but all is the same
March 4th, 2009 at 11:33 am
Someone had a similar question, is there a way to connect the ac adapter directly to the battery input.
February 22nd, 2009 at 8:28 pm
#22 UPDATE Well i bit the bullet and got a new ac adaptor, and viola the computer boots but the battery is still not charging, could be a bad batt. In all my readings no one talked about the center pin, ie i have a barrel connector with the outside being ground, the inner sleave being around 18.5 volts, which is what i have. However there is a center pin that read zero, with the new adaptor the center pin reads 8vdc, I then took the old adaptor apart and did some voltage checks, and found that the cable connectors had grd, 18.5 and 14vdc on the center pin. Ohms check on the center pin cable to adaptor read open, so i have a bad pin. I will update everyone when i get a new connector, I am hoping that the new connector with 14vdc on the center pin may start the battery charging again. Must be something in the circuitry that needs at least 8vdc to allow the laptop to operate. This is on my HP 6710b Laptop. OR
February 19th, 2009 at 12:03 pm
I need disassembly instructions for a Gateway m320. I have searched and cannot find any, I need to replace the dc power adapter.
February 18th, 2009 at 11:06 pm
MY HP 6710b has a similar problem, it will not charge the battery for awhile now. Running on ac power it started intermittenly shutting off and on. At times you can apply force in a pinching movement and the laptop will get power. I have tested the adaptor and it reads good and I can not get it to change at 19v-20v regardless of the twisting I do. I took it to a local pc shop and they said it was my adaptor, but if it is why is it working sometimes on my computer albeit with a pinch or twist? Is there a reason i would have good voltage but still failing? ie current draw? The adaptors here are about 40 bucks non returnable, so I want to make darn sure it is an adaptor before I buy one. Thanks for your replies ahead of time. OR
February 13th, 2009 at 8:27 am
I have a laptop that won’t register the cord. I took out the battery and it runs fine off the cord, wiggling it doesn’t affect it at all. For a while we’ve had to wiggle the cord to get the computer to register it, but now it won’t at all. It says its plugged in, but it won’t charge, just keeps the battery at the same level. Any tips?