So I made my Saturday project this week be doing some work to the front grilles. More specifically hitting them with a few coats of Plasti Dip. I decided to take the bumper off (I know this really isnt necessary but I got curious and wanted the experience). So after dealing with BMW's stupid tabs I finally got the bumper off. After pulling all the plugs for the lights I noticed that there was a cord sticking out of the metal front brace thing. It wasnt attached to anything and theres nowhere for it to be attached on the back side of the bumper. Does anybody know what this is? I was speculating maybe a thermometer? Hopefully theres somebody that knows what I'm talking about and will be able to provide an explanation.

 

I'm not sure but thermometer seems likely, for the tach temp display maybe.

 

Yep, that's your themometer probe for your inside temp. display. It attaches to the backside of your bumper around the turn signal area. It just slides into a plastic bracket. I did the same thing when I removed my bumper the first time.

 

If its just a cord and no black plastic sensor or plug at the end...then you did something wrong.
otherwise, what they said is correct^