three wires on ford Taurus E fan
 

I am doing the e-fan conversion on my FB. I got a ford Taurus e-fan from a 94 Taurus 3.8L. I have three wires coming from the motor, white, black and green with yellow stripe. Could someone tell me which one is for what?

as far as i can remember black is ground, and the other two are two different speeds, you can test which is low speed and which is high speed by trying one and then the other, you want the high speed.

the only way I can get the fan to work is by connecting the white- positive and green- negative and the other way around to push or pull. I can not get the black wire to do anything.

I have a black wire, a brown/yellow wire and a brown/orange wire. The black is ground, one of the brown needs 12v for low speed while the other needs 12v for high speed. Only one or the other is connected to 12v. Just like mentioned above except I only use the low speed. High speed draws a lot of power and I've always stayed cool with the low speed. Mine was a new fan from an online parts supplier, so an original stock fan may have different wire colors.

When I connected the black as ground and any of the other two wires (white or green with yellow stripe) the fan does not work. It only works with the white on positive and green/yellow on negative.
In the end what does the black wire do?

black is ground bro.. and other wires are low/ high speed wires

If it helps, take a look at this write up:
http://www.xenonz31.com/Electricfaninstall.html

On my OE replacement fan I also have these wire colors. Black is ground. Brown/Orange is Low Speed. Brown/yellow is Hi Speed.