i noticed that the A/C was blowing hot air --- this despite the fact the temperature setting was on 72 degrees. essentially, it is acting as if the heater is on.

i adjusted the temperature to the lowest setting but the air is still hot. what on earth would cause this?

someone else drove my car this morning, and i'm wondering if maybe they pressed something? could it be electrical?

 

I don't have an answer for you, but my 2001 S40 did the same thing this summer and then just last night it would only blow cold air regardless of where I had the temperature selector. It is my understanding that the heater controls are all one computer and that none of the switches is available separately. If it is any consolation, mine seems to act weird for a day or so and then be fine again for quite some time.