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Air conditioner not working in low ambient temperature?

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Active Member
Aug 31, 2017
It has started to get into the mid-40s here and we recently had a couple of very sunny days, resulting in the car interior being uncomfortably warm inside after sitting in the sun, despite it being cool outside. Both times this has happened, I left the climate control on Auto and cranked the temperature down, eventually all the way to the "Lo" setting. The system responded by putting the fan on recirc, cranking up the fan speed higher and higher... and not turning the A/C compressor on -- exactly the wrong thing to do! I tried manually turning the A/C on, and the touchscreen said it was on, but never blew cold air. The only way to make it comfortable was to manually select fresh air rather than recirculation, which eventually cooled the car down.

So it's in for service right now, but I suspect this is nothing wrong with my A/C but something wrong with the firmware, given that no errors were in the logs and the system wasn't even trying to turn the A/C on. I'm thinking it just gets confused trying to cool in low ambient conditions. Has anybody experienced anything similar? I'm on 2018.10 (not 2018.10.4).
Update: Service didn't find anything. A/C works. Of course, they didn't actually attempt to replicate the problem I described. I am pretty sure this is yet another new firmware bug -- the car didn't do this last fall when we had similar weather.