If it is a Factory Radio there is No Code. You have to have the Chevrolet Dealer Connect the Tech 2 Scan Tool to Reprogram it.Try:Disconnect Positive + Battery CableWait 2 - 3 Minutes.Reconnect Battery.Turn Ignition ONTurn Radio On.
If that does Not work, then Dealer will have to reprogram
You do not understand...........If you have the Factory Radio:It is a Class 2 DATA RadioThose GM Radios do NOT have Codes.It has to be Reprogrammed at the Dealer by the Scan Tool
Class 2 DATA Radios store information about the Vehicle & is Uploaded to GM ( V.I. N., Year, Make & Model , etc. )