CITROËN DS 5 Handbook page 60

Locking the passenger doors
F Open the doors.
F On the rear doors, check that the child lock
is not on.
For more information on the child lock, refer to
the corresponding section.
F Remove the black cap, located on the edge
of the door, using the integral key.
F Insert the integral key in the socket without
forcing it, then without turning it, move the
latch sideways towards the inside of the
door.
F Remove the integral key and refit the cap.
F Close the doors and check that the vehicle
has locked correctly from the outside.
Unlocking the passenger doors
F Pull the interior door opening control.