What I said.... the AC is physically on it's the indicator not lit for those conditions. It also automatically switches air inlet from outside. It is a defrost mode. It's also described in the user manual. And many other car makes do that. It's just automated to the things we used to do manually. Because the AC is physically turned on the condenser fan will be cycled on. Since the mazda3 has only one fan, that fan does double duties.Ohhh, now that, I have never heard of on any car... Ac coming on without you physically turning it on. That is very interesting, I will switch the HVAC mode and see what happens later today as I would have never thought of that