Answers to Commonly Asked Questions about Keyless Car Entry

Posted on: 6 December 2017

Most cars produced today have some method of keyless car entry and car users prefer these over using the car keys to gaining entry. This article discusses the mechanism of keyless entry, what to do when it fails and how safe it is against unauthorized entry. Read on for details.

1. How does keyless entry operate?

Your car's key or fob has a short-range transmitter that sends a coded signal to an antenna in your car. The code sent by the key should match the one in your antennae for the door to be opened or shut, which is how you key only opens your car and not any other. Active remote keys are ones that require you to press a button to command an action, while passive/smart keys can work without pressing any button. The latter is powered by a series of antennae located around the car, creating a magnetic field between them. Your fob/key responds to this field to transmit the command code.

2. Is my keyless entry system safe?

Security is a major concern for keyless entry systems, given that there are millions of fobs that all somehow should open just one car. This is made possible by custom high-level encryption – 128-bit encryption (the code has 128 characters and so guessing is extremely difficult). In addition, car manufacturers install a program to randomly generate a new code after each use.

This doesn't mean keyless entry is completely safe, however. It is possible for hackers to gain entry to the system, but this will be very long and complicated. For instance, some hackers may send millions of code combinations within a parking lot, and if they hit a working code, that car's doors will unlock. Consider, however, that there are trillions of possible combinations when dealing with 128-bit encryption (those with 56-bit encryption should consider upgrading) and so successful hacking cases have been few and far between.

3. What should I do when my fob doesn't work?

Your key fob can fail for a number of reasons. Before bringing it to a locksmith, you can try the following:

  • Use the backup – fobs often come in two's (be sure to replace one when it gets lost or damaged). Try the backup key, and if it works you'll know it's the other key that's faulty. Sometimes all you need is to replace the fob's battery (also have a backup battery in your purse just in case). If both keys don't work, you may need to contact a mechanic, as the problem will be within the car and not the keys.

  • Reset the remote – sometimes your fob fails because of loss of memory, in which case you can reprogram it, which is a simple process. For this, enter your car using the ignition keys, close all doors and insert the key in the ignition. Without turning the car on, turn the ignition between the first and second settings until you hear a chime. Press a button on the remote and then wait until it chimes again. Next, take out the keys, leave the car and use the keys to lock all doors, then try to use the remote after about 30 seconds. This method works for most fobs, but consult your manual to find out how to reset your own key fob if this doesn't work for you.

If both of these fail, contact a locksmith for assistance.