There are a few sensors. The most obvious one right in the middle is probably the one to detect your wireless remote. Others detect sunlight to adjust the auto climate control. It's pretty cool to test out actually if you are in a garage or somewhere covered and pull out into the sun, you notice the air getting cooler.
thanks for the welcome invitation. Nice forum. I was just wondering if you could use that sensor to make it turn on your lights at night too. I used to drive a chevy malibu with auto lights and it was nice to not look like a jack ass with his light not on at night. The tsx guage lighting makes me think my lights are on but the contrast of the hid bright lights makes me remember, especially when i pull out of a gas station. Sooner or later, i'm gonna drive without my lights on. Dumbass!