Is "auto" climate full auto?

[bimmerpwr]

When I had 2001 M5 and 2003 330xi, I had to push AC button to get cool air in the summer even when the climate control was in "AUTO". It kind of defeated the meaning of "auto" I thought.

In my 2006 Acura RL, when it is set to "AUTO", it is fully automatic. No need to push anything else to maintain the temperature.

In my 2008 E70 4.8, the manual says, when set to "Auto", it regulates "AC" automatically. But it does not seem the case. Only when I push AC button, I get cool air to maintain the temperature settings (say 72 degree in 80 degree weather).

Does E70 X5 not have "full auto" and requires a push of "AC" button for cool air?

Thanks,