Hello eveyone,
How would i know which one is ground..I have red, orange and black wire. I tested with continuity tester and found the red one is hot (positive ?)..now between orange and black wire which one is ground..and which one negative.

red is hot,orange is ground & black is negative

The a/c on my X was possessed and I recently replaced the Aux fan because thats what the moronic mechanic told me to replace when in actuality it was the FSR. So after replacing the FSR I now have cold air coming out of all four vents, as opposed to just the driver side. The problem now is that my Aux fan is on at all times when the vehicle is on. Even with the a/c off, Aux fan seems to be possessed also now and it stays on. Like I mentioned the fan is brand new and me being a fool, I trashed the old one I removed. Is there a madness to this fan that I dont know? How can I test it?

Wouldnt want this fan on at all times to take a toll on my alternator or battery being that is more unnecessary charge being used.

Surely ground and negative on a negative earth 12V vehicle are the same thing?

I am not so sure that hooking up 12V to the wires of the Aux fan is such a good thing. My understanding is that the fan is a variable speed unit and that the speed of fan is defined by a signal on one of the wires... Without knowledge of the type of control signal I think you could risk cooking the speed controller by thumping 12V down the wrong wire!

You have a constant ground (or negative, same thing) and constant juice. The other is a pulse signal. Running 12V to it briefly to confirm what you already suspect- that the fan is bad- should be ok. Open to other methods of inspection if you have any.

I tested with a 12v and the fan did not spin. I bought a new fan for $250 and tested by connecting and it works. So this weekend i am planning to remove the front bumber and install it. Thank you all for you feedback.

Where the hell did you find a new fan for 250 bucks??

Whats strange about mine is that it spins when I turn the car off, post cooling the fan will work.
When I put my A/C on it does not come on and I have the same issue, ice cold on the highway and hot at lights so I havent been using it.
How could the fan be bad if it still spins after driving for post radiator cooling? Is there a control for the A/C which may be bad?

Help...I am not able to take the bumper off. I removed all the 18 bolts and not able to slide..its as if something else is holding...I cannot find any directions for 2004 x5 3.0..I followed the 2001 X5 directions and they are not the same. there is one link for 2004 X5 and the link is not working.
I was reading some other articles and may it looks like there might be another bolt behind the fog lights. I am just afarid that i might break something there.