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2010 Toyota Corolla - AC feels cool when switch isn’t on

Why is my car ac fan is cool without climate control switch on

I have a 2012…same generation. Just make sure the a/c button is off when driving.Could be that the outside temperature was cool that day…my guess!.

If you’re running the windshield defrost (edit: windshield zone setting), it will use AC whether the “AC” button is depressed or not. You could have a stuck/partially stuck compressor clutch or clutch relay. Somehow the “activation” wire (probably a negative/ground trigger), could be damaged and touching chassis ground, or the climate control panel could be faulty. Then there’s the possibility of gremlins… Seriously, I think I outlined every possible cause. You can tell of your compressor is running by watching to see if it’s spinning (which it shouldn’t be of it’s off).