Ditto the replies above in regards to the ambient air temp sensor. I highly doubt it is the culprit of a "no start" situation. Seeing -40°F in the display is only a symptom that the ambient temp sensor has failed in some way...aka the wiring has been damaged or the temp sensor has failed in some way.

I believe it sends data to the DME...which is then shared with other modules like the IHKA & IKE & GM to regulate some of the IHKA's programs, display the temp in the cluster, and to actuate the heated mirrors & washer jets. But there's nothing about the ambient temp sensor that would stop the vehicle from starting.

__________________
Become a BMW CCA member! Click HERE to join and feel free to use my BMW CCA member #191509 as a referral.

• 2015 f06 650ix GC (Moonstone exterior/Cohiba brown Merino Leather interior)
• 2014 f15 X5 50i (Space Gray exterior/Mocha Nappa Leather interior)