
Your car's anti-theft system is an important line of defense against having your car stolen
. However, sometimes that defense system turns against you, and you can end up locked out of the car. Any attempt to open it might be met by a resounding alarm that wakes up half the neighborhood. There are ways you can get your car out of anti-theft mode, but before that, let's understand the reasons why it could malfunction and lock you out.In simple terms, an anti-theft system ensures that your car will
only start with your key, thanks to a transponder inside that is coded to your vehicle. The transponder sends a signal to your car's ignition system, which disables the anti-theft alarm and lets you unlock and start the car. It is, however, more complex than that. A car's alarm system consists of sensors, immobilizers, alarms, transponders, and more.
Car alarms are supposed to be triggered when someone tries to break a window, open a door with a duplicate key, or otherwise tries to force entry into your vehicle. These instances are detected by vibration or motion sensors. Immobilizers then prevent the engine from starting unless you use the correct key with a transponder in it.
Locking your car will activate the anti-theft system, while unlocking the car will disable it. Some cars even use smart keys that use encryption that changes codes with every use, making it harder to crack. Some even have GPS trackers that can track the location of a stolen vehicle. Of course, cars come with physical deterrents like steering wheel and door locks.
Read more: These Are The Cars Our Readers Wish Would Depreciate Faster
How To Tell If Something Is Wrong With Your Car's Anti-Theft System

There are a lot of reasons why your car's anti-theft system can malfunction or give out false alarms. One of the most common reasons why your key won't unlock the car is due to the battery in your key transponder dying. The transponder will be unable to communicate with your car's central locking system and will refuse to unlock.
Anti-theft alarm systems can also be falsely triggered. The vibration or motion sensor can be triggered by extreme weather like lightning, small animals or birds, and even vibrations due to loud music or heavy machinery being operated nearby. Radio or electromagnetic interference can cause alarms to go off too. The system can malfunction due to sensor failure, faulty wiring, or even software issues.
A straightforward way to know if your car's anti-theft system is not running optimally is if your car's alarm goes off and there is no foul play happening. If your car will not start or starts and immediately stalls, it could be due to an issue with the anti-theft system. Another indicator is if your car locks and unlocks immediately after, or vice-versa, when you try to lock or unlock it.
What To Do If Your Car Refuses To Let You In?

In some cases, your car's key fob does not unlock the car, or you cannot start the car at all. In case your car has a key fob, first check if the battery is dead. Sometimes, replacing the battery is all it takes to solve the problem. Also, check that the car's battery isn't dead.
You can also unlock the car using a physical key. These are hidden inside your key fob and easily accessible by opening the fob by pressing or pushing a small clip. Using it to unlock the driver's side door might be enough to deactivate the anti-theft system. If your car has no visible key slots, look for a hidden slot or faceplate under the door handle.
You can also consider resetting or disabling the car's alarm, although this process varies wildly from vehicle to vehicle. In some cases, starting the car with the key, or even keeping the ignition in the on position for a few moments, is enough to reset the car's anti-theft system. Disconnecting and reconnecting the car's battery or removing and refitting the immobilizer fuse, can perform a hard reset for the car alarm system.
Any of these methods will require that you check the car's manual before taking action, so read up. Those manuals also might suggest ways to deal with an uncooperative anti-theft system that's specific to your car -- or you can look to buy a car that's fast, practical, but undesirable to car thieves.
How To Disable The Anti-Theft System?

While not recommended as a permanent solution, disabling the alarm temporarily can be a better fix than trying to continuously bypass the anti-theft system every time you want to use your car. However, you should get your car's anti-theft system professionally checked as soon as possible. In the meantime, however, there are even a few methods for disabling the alarm system that you can try with your physical key.
The first thing you can try is insert the physical key into the car door and turn it to unlock the system. Hold the key in the unlock position for around 30 seconds -- in some vehicles, this will disable the alarm. Another method is to leave the key in the ignition slot turned to the on position for 10 to 15 minutes. After this, check if the anti-theft light on your car dashboard has stopped blinking. Once it has stopped, turn the key off for two to three minutes. After that, try starting the car.
Of course, these fixes are not universal -- no anti-theft system is. Even if they do work, you should treat these as temporary fixes at best and get your car's anti-theft system checked by a professional. After all, thieves have gotten so smart, they can steal modern cars by tapping into a headlight wire. Even if your car doesn't get stolen, there are quite a few car parts thieves love to steal, so it's best to have a functioning alarm just in case.
Want more like this? Join the Jalopnik newsletter to get the latest auto news sent straight to your inbox...
Read the original article on Jalopnik.