2002 Pontiac Sunfire

I'd have to make sure the battery has a full charge and battery connections, coming and going are all clean and tight on both ends.

Next, check the starter circuits, you have a crank relay. Terminal A16 is hot all the time, use a voltage tester check for voltage. Terminal B16 goes hot with the key in the crank position and is wired through the neutral switch. Check applicable fuses, one fuse that is not in the diagram, crank fuse, check that also. Any testing at relay, make sure tranny is in park or neutral and the e-brake is set.

The engine itself isn't froze-up?