Since the lappy now does not have a DC connector at the back and only 3 wires come out of it, I have cut off the connector from the power supply and hardwired it to the wires coming out of the lappy. It works fine this way but no yellow flashing light to indicate battery is charging.

It’s possible that the laptop will not charge the battery because the “+” wire is not soldered properly.
On some motherboard you have to provide “+” power to BOTH sides of the motherboard. When the power jack is installed, both sides of the motherboard are connected through the copper sleeve inside the “+” hole on the motherboard. Thus, you plug in the power adapter into the jack and both sides of the motherboard gets power.

In your case the power jack is missing and it’s possible that the copper sleeve inside the “+” was damaged, it’s common. Take a look at this guide for more info:
http://www.laptoprepair101.com/laptop/2008/10/28/fortify-damaged-power-jack-connection-in-laptop/
It’s likely, that your guy soldered the “+” wire only to one side of the motherboard and the other side is not powered. That’s why the battery is not charging.
Hope you understand what I’m talking about.

Since the lappy now does not have a DC connector at the back and only 3 wires come out of it, I have cut off the connector from the power supply and hardwired it to the wires coming out of the lappy. It works fine this way but no yellow flashing light to indicate battery is charging. Do I take it that whatever problem I have now is not connected to the way the laptop is now powered?

The guy from I bought it used, offered to solder three wires and have them come out of the hole at the back! He has since gone overseas and I can’t contact him. BTW the wires are red, green and blue. I put the red to +ve and green to -ve. The laptop powers up and I can work on the AC PSU, but the blue floats now. If I connect the blue to the red it archs and the lappy shuts down!

My question.

How do I figure out which wires to use to charge the battery?

There is no special battery cable. The battery gets charge from the motherboard.
You’ll have to disassemble the laptop and take a closer look at the place where those wires are soldered. Test it with a voltmeter.

And stop shorting blue and red wires, you can kill the motherboard.

I live in one of these outposts where it was impossible to find a DC connector that fits my Compaq N610C. The guy from I bought it used, offered to solder three wires and have them come out of the hole at the back! He has since gone overseas and I can’t contact him. BTW the wires are red, green and blue. I put the red to +ve and green to -ve. The laptop powers up and I can work on the AC PSU, but the blue floats now. If I connect the blue to the red it archs and the lappy shuts down!

My question.

How do I figure out which wires to use to charge the battery?

Thanks!

Dude I couldnt un solder it so what i did was tore he metal plate off and then it was easier and safer to take off the board cause then each metal comes out piece by piece, I should put a better guide out for people who are not pro techs yet.

If you can make a guide, I will gladly publish it on this site. Let me know when you are ready.

Maybe someone can answer this. I ordered a new power jack connector, and took the old broken one out, then soldered the new one back in. But, I am still not getting anything to power up. Even though, I know I need a new power adapter, I know I am getting power through it, but, when I am plugged into the DC power jack (laptop)… nothing still comes on.

Unfortunately I cannot help you without looking at the laptop. It’s possible that you have to resolder the jack or maybe you have a dead motherboard.
If the motherboard gets power through the jack but the laptop appears to be dead, probably there is a problem with the motherboard.

I just unfortunitly purchased another used laptop, from a repair shop, before I came across this site. I still plan to keep my old Compaq Presario M2000 though, especially now that I found I could order another Power Connector Board off Ebay.