Toyota Prius 2011 Manual page 68

1-3. Opening, closing and locking the doors and back door
Locking the front doors from the outside without a key
STEP 1
Move the inside lock button to the lock position.
STEP 2
Close the door.
The door cannot be locked if the "POWER" switch is in ACCESSORY
or ON mode, or the electronic key is left inside the vehicle.
Depending on the position of the electronic key, the key may not be
detected correctly and the door may be locked.
Rear door child-protector lock
68
The door cannot be opened from
inside the vehicle when the locks
are 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.