We have all had one of those days. You’re rushing to go somewhere, and as you try to start your car, or even unlock it, you realize that your car key is not working. In that moment, when you might be locked out of your car, your mind is racing to try and understand all the reasons why this might be. Sometimes, the answer will easily come to you, while other times it might take a while for you to figure out what the root of the problem is. We’ve all been there, so it is a familiar pain that we share. To make this ordeal much easier for you, should you need it now or in the future, I will take a look at some of the reasons why your car key is not working.

TYPES OF CAR KEYS

To diagnose the root of your problem, first you have to know the type of car key you have and how it works with your vehicle. There is a common misconception that all car keys are the same, after all, they are all used to operate cars, so they must be the same, right? Unfortunately, not. Although car keys and car door locks might be similar in many ways, they are all very unique, which is why bump keys don’t work on cars. This is the reason why it is important to understand the type of car key you have so you can properly diagnose the reason why your car key is not working.

TRADITIONAL CAR KEY

The most common type of car key used to be the traditional car key, which was mostly just a physical key that was used to engage your car door locks and work in conjunction with your ignition. Chances are if you own a vehicle that was manufactured before 1995, then your car keys are the more traditional kind.

Traditional car keys are very similar to the locks on your house. They are a single length of metal, with a series of cuts that fit a specific lock. If you were to cut a key to match the physical appearance of your key, it will start your car and open all the locks. Unless the key breaks, the grooves wear down or the lock cylinders’ malfunction, you won’t have an issue.

You likely have traditional car keys if…

• The key is a single length of exposed metal.
• There is no plastic covering on the thumb turn.
• The key is not attached to a remote.
• Your car does not use an immobilizer (likely in pre-1990s models).

TRANSPONDER CAR KEYS

After 1995, most car manufacturers began pairing vehicles with transponder keys. A transponder key essentially means that your car is now paired with your key in a much more secure way. There is a transmitter embedded within the key that corresponds to a receiver housed within the vehicle. In order for the car to work in the ignition, the transmitter and the receiver have to exchange a series of signals that serve as verification that the right key is in place.

Often the transponder chip is housed in a bit of plastic, covering the bow/thumb turn of your key. If the blade of your car key protrudes out of an attached remote, the transponder chip is likely in the remote. This chip can be damaged, or the receiver for its signal can stop working. If anything is interfering with the signal between the transponder key and the car immobilizer unit, your car will not start. With two communicating parts, it is important to check both when the car key is not working.

You likely have transponder car keys if…

• There is a plastic covering on the thumb turn.
• The key is attached to a remote.
• The car uses an immobilizer (unlikely in pre-1990s models).

KEYLESS ENTRY FOBS

These days, most modern cars have built upon the concept of communication that was introduced by transponder keys. This has led to the keyless entry remote. Keyless entry remotes look like little remote controls, and each button elicits an action from your car. Since these entry remotes are keyless, the key itself works by communicating with your vehicle. This action is similar to the transponder key described above, but in lieu of a key and ignition cylinder, most of these vehicles use push buttons.

Similar to the transponder car key, when the car key fob is not working, there is an issue with the signalling. The most likely cause will be low or dead batteries in the car key fob. But if that doesn’t solve your issue, you will need to troubleshoot more electronic issues. Besides electronic issues, if your key fob is not opening your car doors, you might have issues with your door lock assembly.

You likely have keyless entry fobs if…

• The car has a push to start ignition.
• There is no metal key.
• There is no keyed ignition cylinder.