The security central locking feature allows you to unlock only the driver's door and the tank flap. All other doors and the boot lid remain locked.
Unlocking driver's door and tank flap
Press the 
button on the remote control key/convenience key once or turn the key to the unlock position once.
button on the remote control key/convenience key once or turn the key to the unlock position once.Unlocking all the doors, the boot lid and the tank flap simultaneously
Press the button on the remote control key/convenience key twice within 5 seconds or turn the key to the unlock position twice within 5 seconds.
button on the remote control key/convenience key twice within 5 seconds or turn the key to the unlock position twice within 5 seconds.The safelock mechanism* and the anti-theft alarm* are deactivated immediately even if you unlock only the driver's door, without unlocking the other doors.
You can change the settings for the security central locking system directly on Audi A3s with MMI* ►Link.