The Basics: Car Alarms
While most purchases from the local car electronics shop are purely for entertainment, an alarm's sole purpose is to protect your investment, not only in your automobile and your mobile electronics, but in your personal safety as well. Other safety and security items include remote starters and backup sensors.
Alarms have come a long way from the systems that merely sounded when a door was opened improperly. They now flash the vehicle's lights, disconnect the ignition, and act as keyless car entry systems. Some can even use a computer interface to completely customize their performance. Alarms use a combination of techniques, the most common being motion sensors and dome light detectors. When a door opens, the overhead light comes on, triggering the alarm. Many of today's security systems provide multizone protection, which lets you decide what you want the alarm to protect and selectively arm and disarm individual components.
Most remote starters can start a car from 500 feet away or more, and if you've set your climate controls before you got out the last time, your car will be just right when you're ready to go. While comfort is one advantage, this is also a way to preserve other components--people with a short commute know that mufflers need a certain amount of drive time to blow out accumulated moisture. The extra warm-up time might cut down on the frequency of muffler replacements.
Some car owners feel every scratch and ding on their vehicles as though the damage was done to their own bodies, and accidents they cause themselves are even more painful. People back into things every day, including light poles, garage walls, garbage pails, stray toys and bicycles, shopping carts, and other cars. In addition, the size and design of vehicles these days (think SUVs) make reversing more challenging. While these minor accidents are unfortunate and annoying, incidents involving children are immensely more serious. All of these accidents might be avoided with the aid of backup sensors.
A backup sensor transmits an ultrasonic signal from its mounting position on the back of a car. If the signal encounters an object, it bounces back to a receiver, which can then determine the distance between the transmitter and said object. This works along the same principles as radar; the length of time between the signal's emission and reception determines the distance. The ultrasonic pulses work through all kinds of low-visibility situations, and they are also helpful in the blind spot. Many new systems now combine sensors with a small video camera to really let drivers see what's going on behind them, while others rely solely on a camera and a dashboard-mounted video screen. With the rapid increase in popularity of in-vehicle DVD systems and displays, some manufacturers are now offering cameras specifically designed to work with car audio/video systems.
In no way do these systems replace common sense. They do not offer 100-percent coverage, especially at extremely close range. Always proceed with caution.
How to Shop
Security systems come with a wide range of features. An essential option is a panic alarm, which sets off the alarm via a button on the keyless remote. Dual remotes are handy for cars that generally have more than one driver. Some systems add a safety feature that will turn on the interior car lights when the system is disarmed, allowing for safe entry. A field-disturbance sensor sounds with any movement inside the car, and a back-up battery keeps the system armed even if the car battery dies or is disconnected.
Remote starters are operated from a small controller that is designed to fit on a key chain--most systems come with two remotes to accommodate two drivers of the same vehicle. They can work on their own, but remote starters work more securely and efficiently when used in conjunction with a car alarm system. Not only can they be programmed to start the engine, but also they'll perform basic functions like unlocking a door or opening the trunk with the touch of a button. Check to see that the package you're looking at will work on the type of car you have--automatic transmissions, keyless entry doors, and fuel injected systems are sometimes required. Also, some systems will not work with diesel engines.
You want to look for a backup system that includes all of the required wiring cables and harnesses, and make sure you're comfortable with the installation. Some backup systems can be easily installed at home, but others require professional installation.
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