Engine wire?

[Pstephana]

Hello all. I recently replaced my radiator on my 2002 4.4i X5 and gathered data on this great site to help with my DIY project. While I was in the motor compartment, I noticed a loose wire with end clip just hanging around not attached to anything. The wire/clip seems to be part of a larger wire grouping harness off the right side of the radiator. I wanted to see if anyone might know what it could possibly be?
To give reference showing the wire/clip, I have attached a photo of the wire/clip-#1,
right side of radiator lower hose-#2,
the radiator sensor attached to lower hose-#3.

My car seems to be running fine except the AC/heater fan does not work...could this be related?

Any help would be fantastic!

[civdiv99]

Clips into little box mounted on ledge of the fan shroud just about 1:30 ~2:00 on the fan shroud (from the engines point of view)

Hang on I'll get you the official name.......

[civdiv99]

The little box is your "Automatic air recirculation control (AUC) sensor."

Don't blame me for that name, I'm just the messenger.

Look at your oil fill cap and draw an imaginary line straight fwd toward the radiator. There's a little notch in your shroud. That's where the sensor goes, and the line I see in your pic - colors as best I can make out, orientation, connector, etc, plugs into that little box shaped sensor. Assuming it's where it should be, but since you replaced the rad......