2.0L L4 - Gas, 3.6L V6 - Gas. The auto dimming will darken the mirror automatically when the cars behind you or on the side is too bright or with high bean as well as cars from opposite direction with to bright headlight or high bean. It will then clears back to normal when the brightness reduce from cars in front or behind automatically. Dealership will cost over a hundred dollars just for the mirror + time of installation.
It is easy to remove and mount the new one on yourself without the technician.