65 degrees out and dashboard says -40°

[Shantyhag]

This just started happening in the past 30 minutes, but has repeated with each restart of the car (3 times now).  The dashboard temperature reads -40°.  No C or F, just -40° on what is a fairly temperate San Diego day.  Any thoughts or ideas would be greatly appreciated.  We have the 2017 model.  I've tried four times to upload a photo, but I'm not having any luck.

Edited March 18, 2021 at 01:02 AM by Shantyhag

[jsamp]

Searching through old posts.... The connector for the external temp sensor has a common corrosion issue.  Usually it will default to 50deg when it loses connection.  maybe this is what is happening to you.  One post said the sensor is behind the front bumper.  Maybe you can find the connection and unplug/clean/grease the contacts.

 

There's a reddit post about the -40 from a year ago:  

 

[Shantyhag]

Thank you, JSamp!  Very much appreciated.  I haven't experienced the wild temp swings yet, and I didn't notice any of the climate control issues, re: hot v cold, but I'm betting you're right about the sensor.  If it's corrosion prone, we live in San Diego, close enough to the coast to get sea air.  If something can rust, it probably will.  I've bookmarked the thread and I'll try to report back what I find just to provide closure on the issue.

[Timewellspent]

I have an issue once in a while on my 2015 when the outside temps get in the low teens or below, the display says 50 and the heat will stop coming out the HVAC, because the car thinks it is 50 degrees out. I have had it into the dealership more than a dozen times and they have never been able to fix the issue after many attempts. I don't get how they can't figure out the cause and have a fix for it. I have learned to live with it, but if mine was showing -40 and the outside temps were in the 90's and not being able to get AC, I would not ignore the issue. Good luck with your issue. If you get a fix, please post what the solution is.