Thermostat function for Park mode
Add a family of functions for controlling the car's AC: like a home thermostat, specifically for whenever the car is in Park mode. This "parked car" thermostat functionality would keep the vehicle within a set of temperature limits. The thermostat would also adjust its settings based on the exterior weather conditions: snow, rain, overcast, hot sun. That way it can be smart about how much temperature adjustment would be good enough yet frugal.