Chevrolet Venture 2003 Owner's Manual page 120

To unlock the driver's door from the outside with the
key, insert the key and turn it toward the front of
the vehicle. If your vehicle has power door locks, you
can unlock all of the doors and the liftgate by inserting
the key, turning it toward the front of the vehicle
and holding it there for one second. To lock the driver's
door from the outside with your key, insert the key
and turn it toward the rear of the vehicle. If your vehicle
has power door locks, all of the doors will lock when
you insert the key and turn it toward the rear of
the vehicle.
2-10
From the inside, use the manual or power door locks.
To unlock either front door from the inside, pull back on
the manual lever. To lock either front door from the
inside, push the manual lever forward.