The back door can be locked/unlocked and opened/closed by the following procedures.
Locking the front doors from the outside without a key
Move the inside lock button to the lock position.
Close the door.
Vehicles without a smart key system
The door cannot be locked if the key is in the engine switch.
Vehicles with a smart key system
The door cannot be locked if the engine switch is in accessory or
ignition on mod ...