How to Reset Newer GM Theft lock Radio’s
The following instructions will allow you to reset any newer GM (General Motors), Cadillac, Oldsmobile, Buick, Pontiac theft lock radio.
The theft lock radio must be in “Locked” mode.
1. Turn the ignition ON (The radio should display “Locked”).
2. Hold down the Right Seek and Preset #5 buttons.
3. With those 2 buttons held down, Press the Power button.
This will put the radio in diagnostic mode and allow it to work, you will have todo this trick every time you start your car.
Other then that you will need to make a trip to the Dealership :/