Function of ATA (Anti-theft Alarm system)
If the ATA system is primed, a visual and audible alarm is triggered in the following situations:
a door is opened
the vehicle is opened with the emergency key element
the bonnet is opened
the tailgate/rear-end door is opened
ATA is automatically activated in the following situation:
after the vehicle has been locked with the key
When the ATA system is primed, indicator lamp 
flashes in the overhead control panel.
ATA is automatically deactivated in the following situations:
After unlocking the vehicle with the key.
When the key is inserted into the ignition lock.
The alarm is not deactivated, even if you immediately close the open door that has triggered it, for example.