GM Service Manual Online
For 1990-2009 cars only

The lockout protection feature makes it difficult for you to lock your keys in your vehicle. If the driver's door is open while the keys are in the ignition, a chime will sound and you will not be able to use your power door lock switch to lock the vehicle.

If you don't leave the keys in the ignition or if you use the manual door lock, you could still lock your keys in your vehicle. Always remember to take your keys with you.

To turn this feature off or on, see Vehicle Personalization .