I might add that the electrochromatic mirror technology does not mechanically adjust the mirrors, rather they "dim" the mirrors by causing the mirror to electrochromatically change their reflective properties. In other words, they return a green tinted reflection that grows dimmer as the light source becomes stronger. Only the inside mirror and the drivers side mirror dim, the passenger side mirror doesn't dim.
The twilight sentinal does pretty much what was already answered, the lights are controlled by an electronic light sensor, so at a given lumin factor, the headlights and associated running lights are activated. I think they also are programmable to stay on for a given duration after the ignition is turned off, and the doors are locked. This action activates the sentinal timer for the programmed time, giving the driver illumination for the programed amount of time.
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