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Alarms & upgrades
Car alarm basics
Car alarms have been around for years and most people associate them with the loud, unrelenting screeching noise they make, typically around 1am, just as you are about to enter your deep sleep.
Nonetheless, they are designed to prevent someone getting into your car when you don't want them to. Many now come with the following as well:
Check out the alarms buyer's guide to see what to look for.
Jargon buster
You may come across the following jargon or terms when looking for a car alarm.
Use the quick links below to navigate more quickly:
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
Alarm
This system sounds an audible and possibly visual warning when the vehicle is tampered with.
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 and no doors are opened within a period of time (usually 30 seconds) the alarm will re-arm itself.
Auxillary output
An output that can be controlled from the remote control. Useful for control of electric boot releases, add-on engine starters, neon lights etc.
B
Battery back up
A siren that has its own battery, which allows the alarm to continue to sound even if the car battery is disconnected.
Bonnet release
Usually a function in the remote control where you can open the boot by pressing a button.
Bonnet switch
Detects when the bonnet is open.
C
CDL
Stands for (C)entral (D)oor (L)ocking.
Central door locking
Many alarms now link into, and control, your car's central locking. Central locking will be activated or de-activated with the alarm.
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.
D
Dead Locking
This disables the normal lock functions and prevents a thief opening the car from the inside by breaking the window and operating the release handle or button.
E
Emergency override
A feature enabling you to override the alarm if your remote control is lost or stops working.
G
Glass Break Detector
This sets off the alarm if a thief breaks a car window.
I
Ignition locking
A safety feature where the doors are automatically locked when the ignition is turned on.
Immobiliser
An immobiliser stops the vehicle from being driven away. There are two types:
1. Mechanical: These lock either the steering wheel, gear lever or pedals in position.
2. Electronic: These disable the vehicle's electrical system and engine. This sets off the alarm if a thief breaks a car window.
Inclination sensor
This sets off the alarm when it senses the vehicle is being raised or jacked up to tow the vehicle away or steal the wheels.
L
Last door arming
See Passive Arming.
LCD display
A display on the remote control itself. This give visual confirmation that the alarm is armed, which detector has triggered it and if the emote engine starter is operated.
LED
Flashing light usually installed on the dashboard to indicate that the alarm is switched on.
M
Microwave sensor
A sensor that detects movement inside the car, but is not susceptible to air movement. Designed to reduce the possibility of false alarms on soft top vehicles.
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.
P
Paging
A paging device sends a signal to the owner, telling him the car is being attacked or stolen.
Panic feature
Allows the alarm to be set off from the remote control for personal protection.
Passive arming
The alarm/immobiliser is switched on automatically when you leave the car.
Passive locking
The same as passive arming but the doors also lock.
Perimeter Protection
If a thief opens any doors, boot/luggage areas or the bonnet, the alarm will go off.
R
Radio Key (Remote Control)
A tiny radio transmitter, which may operate the alarm/immobiliser and/or door, locks.
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.
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 the remote to start to pre-warm or cool your car from the comfort of your house.
S
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.
T
Total Closure/Central Locking
Enable the whole car (doors, boot, sunroof) to be locked with just one operation of a key or remote control.
Touch Key
A key which operates the alarm/immobiliser, by direct contact with the keypad.
Transponder
This is a uniquely coded identification microchip, which can be used in an immobiliser key to help prevent a vehicle from being stolen.
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 the remote control is used to start the engine (Remote engine starter).
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.
U
Ultrasonic detectors
A device that detects movement inside a vehicle.
V
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.
Volumetric Sensor
This sets off an alarm if a thief enters the vehicle.
W
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 if someone is 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.
Z
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.
Reviews & ratings
See our reviews and ratings section for other car owner's views.
