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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March 2nd, 2010 at 8:09 pm
I had purchased a new external power supply (mine was chewed on by the cat). It worked great for a few days then the internal power supply was loose so I followed these directions . YAY laptop is as goos new. Thank you thank you thank you for your help.
February 15th, 2010 at 11:52 pm
i wish this applied to mine but i need a new battery, so what your saying is like foreign to me.
February 9th, 2010 at 4:51 pm
Liminal,
I think you can use this DC-IN harness – part number P000484410. Google the part number and you’ll find it.
February 8th, 2010 at 1:44 pm
I have a Tecra too, though a different model (Tecra A9) and I’m having a similar problem. Where would I be able to get a DC-in harness that would be suitable for my laptop? The one I would need would require a much longer cable coming out of it
Thanks for the help and the excellent advice given here by the way!
January 25th, 2010 at 6:33 pm
I have a gateway mx6214 laptop. When I try and charge it the charging led blinks off and on pink and will not charge. The battery is new so its not the battery.
January 14th, 2010 at 10:10 am
Pls my hp pavilion dv6000 laptop can’t charge my laptop battery,i have tested the power jack and all seems.Is there any way i can find where the problem is?