There is no separate switch, that I'm aware. The mirror heaters are activated when in front defrost/defog mode. I vaguely recall that from perusing the manual I believe.

 

^ He's right. The heated feature in the side view mirrors is activated when the rear defroster is turned on. I have that as part of the Premium package in my car.

 

Something I'm not too fond of the auto headlights feature is the fact that I have stock HID's, and when I drive under overpasses or tunnels with the auto feature kicked in, the HID's would turn auto turn on/off many times which could decrease the life of the HID's. So I usually keep the light stalk in the off position during the day, and hit the auto position at nighttime.