Use our VIN decoder page. Go to "jolly's......page" at top left. Click on "VIN Numbers" in the colored menu. Scroll down and read. As said "C" means Chevrolet. If the decoder you used said C-15, it's a Chevy decider or a bad decoder. We have the official.
you will have a 1502xxxxxxx............if you don't, better let us know what it is.