CITROEN Grand C4 PICASSO Owner's Handbook Manual page 71

Normal locking
Turn the key towards the rear of the vehicle
to lock the vehicle completely.
Deadlocking
Turn the key towards the rear in the driver's
door lock to lock the vehicle completely.
Turn the key towards the rear again within
five seconds to deadlock the vehicle.
Depending on your version, the
direction indicators flash for a
few seconds, the door mirrors fold.
If your vehicle has an alarm, this
function is not activated by locking with
the integral key.
Access
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