Battery Light on?!, Please help Options

[99GT]

Alternator went out, burnt some wires. Got fresh wires soldered in to replace the burnt ones.
Now the car is in good and running order, nothing inside seems sluggish. I had everything I could on while driving 10 mile trip to and from.
E lights, rear defrost, wipers, radio full blast, heat full blast. The car made it without no issues.

No corrosion at battery.
Charged the battery before putting in, but battery was good previously.
I also tried a different good working battery. (light still on)
Battery cable ends are tight.
All the negative cable, and grounds are tight on both ends.
Alternator belt is secure and tight, but not too tight.
All the connections on the alternator are secure.
Brand new alternator.

Please help. I'm stumped.

This post has been edited by 99GT: Jan 3, 2009 - 10:35 PM

[GriffGirl]

Any lights on other than the battery light? Does it go off and on at times? I'm having the same problem - battery light is on and eventually after driving a little while, the airbag light comes on too. Drove hard over a pothole this morning and the battery light went out and didn't come back on the whole way to work.

I've narrowed it down to a bad ground or bad alternator. I also very recently replaced my alternator, and then the battery (which it turns out I didn't need to replace, so now I've got 2. )

Check all your grounds. One of mine completely melted (which was why I couldn't start my car, and erroniously bought a new battery). I replaced that ground and then it was good for a few days, and then the light came back on. So I replaced other grounds, added a few, and still - evil red rectangle. I keep being told too that it's a regulator issue, which means the alternator is bad. I was also told that testing the alt won't always tell you there's a problem; it might just tell you there's a generic "charging system" problem which is really vague.