GM Service Manual Online
For 1990-2009 cars only

This feature will delay the actual locking of the doors and liftgate when the power door lock switch or remote keyless entry transmitter is used to lock the vehicle.

If any door is open when locking the vehicle, three chimes will sound signaling that the delayed locking feature is active. Five seconds after the last door is closed, all of the doors and liftgate will lock. The turn signal lamps will flash to indicate that the doors have been locked. To cancel the delay and lock the doors immediately, press the lock button a second time.

If the key is in the ignition this feature will not lock the doors.

If your vehicle has a Driver Information Center (DIC), you can disable this function. See DIC Vehicle Personalization .