For 1990-2009 cars

A vehicle with power door locks has the delayed locking feature which delays the actual locking of the doors when the Remote Keyless Entry (RKE) transmitter is used to lock the vehicle.

If any door is open when locking the vehicle using the RKE transmitter, three chimes will sound signaling that the delayed locking feature is active. Five seconds after the last door is closed, both doors will lock and the parking lamps will flash. To cancel the delay and lock the doors immediately, press the lock button on the RKE a second time.

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