ANTI GRAB: See Random Encryption.
ANTI HIJACK: Prevents a thief forcing a driver to hand over his keys and driving off with the car.
ANTI SCAN: The alarm will ignore a device such as a radio scanner which bombards it with multiple codes in order to find the correct code.
ARM CONDITION MEMORY: If the power to the alarm is disconnected it remains in the same state when it is reconnected so that the alarm cannot be disarmed by disconnecting and reconnecting the power.
AUTO RE-ARM: Prevents accidental disarming of the alarm. If the alarm is disarmed an no doors are opened within a period of time (usually 30 seconds) the alarm will re-arm itself.
AUXILLIARY OUTPUT: An output that be controlled from the remote control. Useful for control of electric boot releases, add on remote start modules, neon lights etc.
BATTERY BACK-UP: Allows the siren to continue to sound even if the car battery or alarm wires are cut.
BONNET SWITCH: A device to detect when the cars bonnet is opened.
BOOT RELEASE: An output that be controlled from the remote control and used for control of an electric boot release.
CDL: Short for Central Door Locking
CENTRAL DOOR LOCKING: Most alarms will also control your cars central locking so that the doors are locked and unlocked when the alarm is armed and disarmed.
COMPACT ALARM: An alarm that has all the electronics built into the siren. Generally considered less secure than a modular alarm and more susceptible to water damage of the alarms electronics.
EMERGENCY OVERRIDE: A method of overriding the alarm should the remote control fail to function or is lost.
IGNITION LOCKING: A safety feature where the doors are automatically locked when the ignition is turned on.
IMMOBILISER: Cuts a vital electrical circuit off preventing the engine from being started.
LAST DOOR ARMING: See Passive Arming
LCD DISPLAY: Some alarms have an LCD display built into the remote control. This give visual confirmation that the alarm is armed, which detector has triggered it and if the remote engine starter is operated.
LED: Flashing light usually installed on the dashboard to indicate that the alarm is switched on.
MICROWAVE DETECTOR: A device that detects movement inside the car, not susceptible to air movement inside the car. Can be used with convertibles even when the roof is down. A dual zone detector will also sound the Warn Away chirps on some alarms if someone gets too close to the vehicle.
MODULAR ALARM: An alarm that has the electronics and siren built into separate boxes. As the alarms electronics are inside the car these type of alarms are more secure and less liable to water damage than a compact alarm.
MUTE MODE: Allows you to arm or disarm the alarm without the confirmation chirps from the siren. Handy when coming home late at night so you don't disturb your family or neighbours.
PAGER: Send a signal to a receiver to let you know that the car is being broken into with a range usually around half a mile in ideal conditions.
PANIC FEATURE: Allows the alarm to be set off from the remote control for personal protection.
PASSIVE ARMING: The alarm automatically arms itself 30 seconds after the last door is shut should the owner forget to turn on the alarm.
PASSIVE LOCKING: The same as passive arming but the doors also lock. Be sure not to leave your keys inside the car if enabling this feature!
RANDOM ENCRYPTION: The remote control changes its code every time its used preventing anyone from copying the code.
REMOTE CONTROL: A keyfob style device for arming and disarming the alarm. Some models also feature a built in pager or LCD display to alert you when the alarm goes off.
REMOTE ENGINE START: A convenience feature on some alarms which allows you to start the cars engine from the remote control. By leaving your heater or aircon turned on when leaving your car you can use remote start to pre-warm or cool your car from the comfort of your house.
SCANNER: Series of flashing lights used to indicate that the alarm is switched on. Offers higher visibility than a standard LED.
SELF CODING: A method of easily programming in new remote controls without having to visit a dealer.
SHOCK SENSOR: A device that detects knocks, bangs or impacts to the car. A dual stage sensor will sound the Warn Away chirps on some alarms if there is only a light knock only setting the full alarm off with a heavier knock or impact.
SILENT ARM/DISARM: See Mute Mode.
SMART CHIRPS: A series of chirps when disarming the alarm to alert you that the alarm was triggered during your absence.
TOTAL CLOSURE: A feature of some vehicles where you can lock all the doors and close all the windows and sunroof from the drivers door lock. If the cars windows close when you lock the drivers door and hold the key in the locked position then alarms with this feature can also close the windows when the alarm is armed. Also see Window Closure.
TRANSPONDER BYPASS MODULE: Required on most vehicles from 1997 (and some earlier) for remote starters to function. Allows the alarm to turn the factory fitted immobiliser off when remote start is used.
TURBO TIMER: Some alarms with remote engine start also have a turbo timer feture which allows you to leave the car and arm the alarm whilst leaving the engine running for 3 minutes to allow your turbo to cool down gradually.
ULTRASONIC DETECTORS: A device that detects movement inside a vehicle.
VALET MODE: When in valet mode an alarm will only operate your central locking, all other alarm features are disabled. Ideal for valet parking services and when taking your car in for servicing.
WARN AWAY: Sounds a series of short chirps from the siren to alert people that the alarm is armed. Used with dual zone microwave sensors to detect someone too close to the car or dual stage shock sensors to detect light knocks or bangs.
WINDOW CLOSURE: An add on for cars without Total Closure which allows the windows to be closed automatically when the alarm is armed.
ZONE BYPASS: Prevents repeated false alarms from a defective or poorly adjusted sensor. The alarm disables a sensor if too many alarm activations occurr in a short time during one armed period. The zone is restored to normal operation when the alarm is next armed.