My son got this 2003 CTS from his grandfather. I have been out of town and he bought a new battery. Come to find out it must have been the alternator. I got home and charged the battery and put it back in the car. First time I did it I got no lights or anything but the clock in the dash ran backwards a few times. I charged the battery again just to make sure and when I put it back in I get nothing. I have checked the battery and get power to the fuse box under the hood. I have no power to the car anywhere and can not get it out of Park. Keys were locked in but reading old forums now know how to get them out when the get stuck. Anyone know anything about this or heard anything about this happening.