[bigdog]

i own a 2005 cobalt ss supercharged and a friend of mine pointed something out to me.The is a clear dome type button on the dash close to the windshield...i thought it was maybe a thermometer that measured the temp outside but im not sure. does anyone know what it could be?

 

[Josh]

jrever has it right, I have the same car and thats what it is. It is the light sensor that tells the car when to turn the heasdlights on. The thermometer is on the outside under the hood on the left side of the radiator.