Lexus 2012 RX450h Owner's Manual page 80

1-3. Opening, closing and locking the doors
Locking the front doors from the outside without a key
Move the inside lock button to the lock position.
STEP 1
Close the door.
STEP 2
RX350
The door cannot be locked if the "ENGINE START STOP" switch is in
ACCESSORY or IGNITION ON mode, or the electronic key is left
inside the vehicle.
The key may not be detected correctly and the door may be locked.
RX450h
The door cannot be locked if the "POWER" switch is in ACCESSORY or
ON mode, or the electronic key is left inside the vehicle.
The key may not be detected correctly and the door may be locked.
Rear door child-protector lock
80
The door cannot be opened from
inside the vehicle when the lock is
set.
These locks can be set to prevent
children from opening the rear
doors. Push down on each rear
door switch to lock both rear
doors.