Lexus 2003 LS Owner's Manual page 35

Auto door locking function*: All the doors will lock
automatically when the selector lever is moved out of "P"
position. This auto door locking function is operable if any
doors are unlocked while the ignition switch is in the "ON"
position.
NOTE: *This setting can be changed as in the following:
B All the doors are locked automatically at 20 km/h (12
mph) or higher vehicle speed. However, if any door is
unlocked during driving, this auto locking function does
not operate until the unlocked door is once opened.
B When the selector lever is moved out of "P" position and
the brake pedal is held off your foot, this function is
enabled.
Ask your Lexus dealer for details.
Door closer (some models)
If any door is closed but does not latch shut, it
automatically closes completely. This system is equipped
on all the doors and will activate regardless of the ignition
switch position.
Pulling the door handle will cancel the door closer, allowing you
to open the door which is about to close. However, pulling the
door handle of the rear door which is locked with the child
protector will not cancel the door closer.
CAUTION
A Careful attention is needed so as not to get your
fingers trapped as the door automatically closes
when the door has not been fully closed.
A Never allow a child to operate the door.
KEYS AND DOORS
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