I think you can check for the siren, by remove the cover for the coolant reservoir fill, and look in the corner at the base of the windshield on that side... you can see if the "Siren" unit is in there. you need that to make the chirps, for this particular config option to work, audible locking.
There are different levels of "alarm" it might be it works even if you don't have the siren unit ("BBS" ECU). It could use the horn. US cars mostly don't have the motion sensor (IMS) and they don't have the siren unit with the tilt/inclination sensor that detects the car being towed. They still have the basic siren, used in an "alarm" function, open the door without remote unlocking first and the siren will go off. US cars have the siren present though since they all have the audible locking feedback enabled as original I beleive.
Only the car with the IMS motion sensor, has the "reduced guard" button in the Sensus. Otherwise there are no controls for "alarm" functionality.
There are different levels of "alarm" it might be it works even if you don't have the siren unit ("BBS" ECU). It could use the horn. US cars mostly don't have the motion sensor (IMS) and they don't have the siren unit with the tilt/inclination sensor that detects the car being towed. They still have the basic siren, used in an "alarm" function, open the door without remote unlocking first and the siren will go off. US cars have the siren present though since they all have the audible locking feedback enabled as original I beleive.
Only the car with the IMS motion sensor, has the "reduced guard" button in the Sensus. Otherwise there are no controls for "alarm" functionality.