GM Service Manual Online
For 1990-2009 cars only

Your vehicle has an automatic transaxle shift lock control system. You must fully apply your regular brakes before you can shift from PARK (P) while the ignition is in RUN. See Automatic Transaxle Operation .

If you cannot shift out of PARK (P), ease pressure on the shift lever by pushing it all the way into PARK (P) while keeping the brake pedal down. Release the shift lever button. Then move the shift lever out of PARK (P), being sure to press the shift lever button.