Does anyone know where this connector attaches??

[DTW88]

This mystery connector is hanging under the front bumper on (US) drivers side. It is round with a blue and brown wire. It runs up and over fender in engine bay, im not seeing its source?

[peterman]

It should be your ambient temp sensor I think. Do you have an iS? brake ducts in place? look inside it to see if there is a TC hanging out in there.

Edit: See attached schematic.

[DTW88]

It is 88 e30 325e, ill peek around more and see if i can find anything.