There are two security features on a Ford. One is a personal alarm system that makes a loud noise if someone tries to break into the vehicle. This is turned on and off using a remote control key. The other system is a passive system called the Securilock. This prevents the engine from starting without the use of a coded ignition key. This is the key that comes with the vehicle from the factory that is specially coded to start the vehicle.
Examine the remote entry key and find the loudspeaker icon. Press this icon to turn on the personal alarm. This will sound the alarm.