Theft systems are designed to go into effect and make it impossible for a car to start if the wrong key is used. Unfortunately, worn keys can accidentally cause this problem to occur and make it impossible to start a car. Thankfully, this problem can be managed and repaired.

Worn Keys Can Trigger An Anti-Theft Warning

Modern cars are designed to work with specific keys. The anti-theft systems in these vehicles note the shape of the key and alert the computer if the key is improperly shaped. In some instances, though, the proper key may be slightly worn down through wear and tear. Though the ignition accepts the key and starts the car, the theft system does not recognize it.

As a result, there is a disconnect between the car's computer and the car's ignition. While the mechanical ignition is more forgiving of slightly worn keys and starts without a problem, the anti-theft system has likely already sent dozens of warnings to the system about the key.

Knowing If The Anti-Theft System Is Failing

When starting the car, take a look at the dash and wait for the anti-theft light to flash. If it flashes for a moment or even continues to flash, there is a chance the system is troubled. This is especially noticeable if the car refuses to start and the anti-theft system light is blinking. The engine won't even attempt to turn over in these instances. Just how does the anti-theft system get to this point and cause such a difficulty with the car's engine? By sending warning signals to a car's computer. 

Resetting Your Computer May Help

When the worn key activates a theft warning, this warning is stored in the memory system in the car computer. If too many warnings compile, the car will refuse to start. However, resetting the computer may be able to help here.

This process requires unhooking the car from its battery and letting it sit for several minutes. Without power, the computer will eventually shutdown and restart. In some instances, this may be enough to clear the memory of the anti-theft system and make it possible to turn on the car again.

Unfortunately, this is a fix that may only work on certain cars. Even in those it does work on, it may be only a temporary fix. The theft system will still malfunction when the worn key sends too many theft warnings to the system. A professional auto repair shop can replace the theft system and the key to eliminate this problem.