Buick 2004 Regal Owner's Manual page 72

Power Door Locks
The rear doors do not have power door lock switches.
2-10
The vehicle has front
power door lock switches.
Press the top portion of
a door lock switch to
unlock or the bottom
portion to lock all doors.
Programmable Automatic
Door Locks
Programmable power door locks are intended to provide
enhanced security and convenience by automatically
locking and unlocking doors under certain conditions.
The doors can be set to one of four operating modes.
Mode 1: Doors do not lock or unlock automatically when
the transaxle is shifted out of or into PARK (P).
Mode 2: All doors automatically lock when the transaxle
is shifted out of PARK (P), but do not unlock automatically
when the transaxle is shifted into PARK (P).
Mode 3: All doors automatically lock when the transaxle
is shifted out of PARK (P) and automatically unlock
when the transaxle is shifted into PARK (P).
Mode 4: All doors automatically lock when the transaxle
is shifted out of PARK (P) but only the driver's door
automatically unlocks when the transaxle is shifted into
PARK (P).