Abstract: A complementary security system for installation, at least in part in a vehicle, has an Original Equipment Manufacturer (OEM) security system installed therein. The complementary security system for communicating an alarm condition beyond the communication range of the OEM security system. The complementary security system comprising: a control module for receiving a trigger signal being indicative of the alarm condition detected by the OEM security system; a communication module for transmitting by Radio Frequency (RF) an alert signal upon receipt of the trigger signal by the control module; and a remote transmitter for alerting a user upon receipt of the alert signal. The remote transmitter being located beyond the communication range of the OEM security system. A corresponding method is also described.

Abstract: A vehicle security system for performing selectable vehicle security functions that are programmable in a wireless manner. The system has a microcontroller controlling a vehicle security interface including at least a siren control unit and a vehicle head/signal light controlling unit. A physically independent remote programming unit is used for transmitting function-programming information to the microcontroller, and a radio receiver is connected to the microcontroller for receiving function-programming information transmitted by the remote programming unit. The remote programming unit includes a switch array for setting up a security function code pattern representing the selected security functions. The remote programming unit also includes a radio transmitter for sending, in an electromagnetic transmission, the function-programming command in a signal string representing the security function code pattern to the microcontroller.