I previously owned a 2007 Cobalt. I'm now looking at a 2008 Cobalt LT, but while test driving it, the "Cooling Mode On" light has come on 4 times. It's still under warranty, but the dealer said they have not been able to find anything. In fact, the light has not come on for them. I'm real leery about purchasing this car. Has anyone else had this problem? Is it serious? Can it be fixed? What exactly is going on? Thanks.