You'll probably have to do the security relearn. I don't remember what all is envolved but its like key one for 15 minutes, off for one, on for 15, off for one... It's a long drawn out process without a TechII scanner. Search over on LS1Tech for "security relearn". It's most likely posted there.

Did you check for blown fuses?

http://www.fullsizechevy.com/forums/...d.php?t=164702