Ok, I don't have my camera with me at the moment, so hopefully I can describe this well.
I have an 05 GP GT, and in the front, down in the air dam where you can see through to the radiator, there's this wiring hanging down. At the end of it is what looks very similar to the plug or harness used at the headlights, but there's this odd... thing plugged into it. The object plugged in is black and extends a little, and then has this white part (all of this being made of plastic) that can move on a hinge.
I'm just thinking it should probably be mounted somewhere specific, but I have NO idea what it is, and it's been hanging quite a while.