Before I get too far into it, the car just had the head rebuilt, which surprisingly, required the front end to be removed from the car.

Ok, so to me, -40F says the system is maxed out. So it's either a short to ground or has a constant 12V applied to it. My guess is it's shorted to ground, like a wire is pinched or something like a loose connector.

My guess is that the sensor is located behind the front bumper. Can anyone give me a little further guidance than that?

Danke

 

It is indeed in the front bumper (left side, IIRC). As I recall, the -40 occurs when the wire is not plugged in to the sensor. Can't remember if you have to remove the bumper to connect it.