I was on a short trip last week in my 2011 ES. The outside temp was around 10 degrees. Unless I set the climate controls to 66 (or lowest) heat in car was too hot. Has anyone had this issue? Also I noticed that I had the AC shut off. Does the AC play a part in adjusting the cabin temp even when it’s really cold outside? Thanks

 

I found an old 2013 post that is asking the same question.

Member IceBlast said the following
“A solution to your outside air problem:
When it is cool outside, you have to turn A/C off (no green light), set the temperature to lowest possible (LO) and ensure the fresh cabin air button is enabled. In this setting you get whatever temp is outside, inside the cabin.”

So if I set climate control to LO this does allow cold outside air into the cabin with cabin fresh air set to on. Otherwise It appears that AC does have to be on when CC is set to a temperature higher than LO.
This appears to be normal operation.

 

your temp sensors, flaps, engine coolant, and a/c all play a part in regulating your cabin temp. temp sensor control the flaps, which allow either hot air from coolant or cool air from a/c to pass thru. hot air is genrated by heater core. cool air is generated by evaporator. flaps regulate amount of air that passes over these and into the cabin. if it is cool enough outside, you dont need a/c, fresh air will work. but for defrosting, your a/c kicks in to dry the cabin air. that is it in a nutshell.....

soooooo..... one potential problem you could have is your temp sensors think it is cold, forcing the flaps open allowing too much hot air to pass over heater core. you are countering that by turning on the a/c

or...... you have a flap stuck open, allowing too much hot air in, and you are countering that by turning on the a/c

 

Thanks for the advice. I think I’ll go to the dealer to get it checked out.