I stole this pic from Iconoclast's dashboard repair thread. The round thing in the middle of the dash? My truck has been missing it since I bought it 6 years ago. I would like to find one to cover the chip that is there, but I do not know what it is called to do a search.

 

HVAC sensor

 

see, I would have never guessed that. I would have thought alarm or light sensor. Thanks! now to do a search so I can cover up that nastiness on my dash

 

It's a light sensor, apparently it bumps up the AC when the sun is bright.

 

Actually Art, that is a picture of my dashboard repair. I recognize the background! I won't bill you for copyright infringement!

 

Domino's Pizza sensor. When you pull in the drive thru they know to have the pizza ready and out the window for you to grab. Just a guess, could be wrong.

 

Art, if you haven't found it yet I think the part is JFT100190
The manual describes it like this:
Sunlight sensor - The sunlight sensor consists of two diodes that provide the ATC ECU with inputs of light intensity, one as sensed coming from the left of the vehicle and one as sensed coming from the right. The inputs are used as a measure of the solar heating effect on vehicle occupants. The sensor is installed in the centre of the fascia upper surface.

 

sorry, typo on part number, that's JTF100190, not JFT100190, not enough coffee yet this morning.

 

Thanks I found on on ebay. Not that it really matters, I never use the Aircon, I just got tired of looking at the broken chip in the middle of the dash and wondering what it is