If you look on the backside of the housing of your headlamp assembly, you will notice that in one spot, there is a slight bulge box shape. Take a small 1/4" bit and drill in just about a 1/4" inch. It will take up to a week, but your creating a weep hole for condensation to release out into the atmosphere.
2009 Cobalt LS XFE U74
Mods: K&N Typhoon Intake, Option Cat-Back Exhaust, Cosmo Short shifter, Maxxim Ahead 17X7's, MPx shorty antenna, FE5 Strut/shocks, Tein S Techs, Moog endlinks, Moog spring seaters, ZZP shorty header, LSJ downpipe, LNF front grille