Will not hold charge, touch power cord on back or move it any way and the computer shuts off, the third light bar on front of computer keeps flashing between red and green

DC Power Jack is bad, or it's solder connections to the motherboard.

To explain;
The DC Power Jack is the port you plug your AC adapter into. (Charger)

Your DC power jack Not installed looks like this,

http://www.megaemarket.com/dc-power-jack-for-dell-inspiron-laptop-b12120130.html

(You can click on the photo to enlarge)

Looking at the jack in the photo, it is upside down in relation to how it actually sits, on the motherboard.
Those flat pins you see go down through the motherboard, and are soldered.

As I'm sure you know, your laptop uses DC electricity. (Direct Current. A flashlight battery, and your laptop battery are examples of stored DC electricity. The AC adapter converts AC electricity into DC for the laptop)

The round metal pin in the center is for Positive. It is the Positive connection. The outside round hole has the Negative connection. (For this jack I believe it is a flat strip of metal going down the side of the hole)

What you can't see is that the body, or outside shell of this DC Power Jack is composed of Plastic. Looking at the photo, look at the rear view of the jack. The view on the right of the photo.
That metal center pin is riveted to the flat pin. (Or Prong, if you wish)

Doesn't take too much of a bump, when the AC adapter plug is installed into the jack, to break the plastic at this point.

However your jack may not be broken. It could be cracked solder joints. Solder joints where those flat pins are soldered to the motherboard.

I apologize for being so lengthy, but unless you repair these babies, you may never know this information, and I thought I would share.

I wanted you to know what the problem is.
It is my belief without looking at this laptop, and based on many repairs, that your DC Power Jack has cracked solder joints.

Only a professional, competent, tech will know for sure when they go to repair it. If the above is the case they will re-solder the joints.

Repair cost? This cost varies from city to city, and country to country. I could only hazard a guess.

In my area it varies from $50 on up. (The cost of the jack online is about $9 should one be needed)
(The entire laptop needs to be disassembled down to the bare motherboard. {The LCD screen stays intact} Then work on the jack can ensue)

If the laptop battery is more than 3 - 4 years old then the battery could be worn out. Recharageable batteries have a finite number of charge and discharge cycles and will lose their capacity over time until they won't charge up at all.

Check power adapter’s DC plug that connects into the laptop power socket with a multi-meter, the voltage should be slightly higher than the voltage that is printed on the label on the bottom of the adapter. If the voltage is zero or way below the voltage that is printed on the label then the power adapter is faulty and needs to be replaced.

If the adapter is OK then connect it to the laptop and power it up, then look at the power/battery charging LED light and wriggle the power plug in the laptop's power socket. If the power/battery LED light flashes and in a certain position this LED light stays firm, then the power socket is either faulty or it has a dry solder joint where it is connected to the motherboard.
This can be repaired but it requires the laptop to be completely dismantled to get at this power socket and repair. I suggest you get a quote first.

Hi,

Your battery has developed some faults that's why it s behaving the way in which it was behaving. Pleas visit your laptop manufacturer and ask for a battery according to specifications. his should cost you less than $200.

Good Luck

It could be a couple of things but it sounds like either your power cord or your power connector on your laptops mother board has a short hopefully it's just your cord you can get these fairly cheap on Ebay if the short is on your board you will need to bring it to a technician just inspect your power cord see if the tip of it moves easily if you can move it around and it has a lot of play its most likely your power cord it if it does not move you still may have problems in the cord itself try changing it as your first method of repair then go from there the reason the lights are flashing is becaus there is a short some where and it's switching from house power to battery power green is house red is almost dead battery power...

Sounds like, the DC power jack of this laptop needs to be replaced or repaired. The part is less than $10.00.
The DC power jack is soldered to the motherboard, It is a simple job if the person knows how to solder, the laptop has to be taken apart though, may not be easy without damaging something..

Best of luck
N Sabre

The plug needs to be resoldered to the motherboard. This need to be done soon as the arcing connection can damage the board. When the connection comes loose from the board the battery can not charge.