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8 Reasons Why Your Car Key Is Not Working

Car Key Not Working

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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

In order to diagnose the root of your problem, you have to first know the type of car key that 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.

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.

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.

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.

Why Your Car Key Is Not Working

Now that we have brushed over some of the differences in car keys, let’s dive right into some of the reasons why your car key might not be working. Keep in mind that if your car key is broken, or if you broke your car key off in the lock, the points below will not help you. Instead, I suggest that you reach out to a locksmith that is skilled in handling broken car key extractions. Let’s begin:

1. Damaged Lock

Repair Car Door Lock

If your car key is not working when you attempt to unlock your car, there is a possibility that the lock itself is damaged. If you drive a fairly modern car, there is less of chance that you will have to deal with this, which is mostly attributed to the presence of key fobs and keyless entry remotes. However, if you have an older model car that still requires you to unlock your car door with your key, you might come across this issue. It is very likely that your car key is not working because the lock is faulty, or worn down. Car door locks work in conjunction with keys, which means that if you are constantly using your car key to physically unlock your car door, the internal mechanism of the lock will wear down over time.

This is not the only way that your car door locks can be damaged. Since these locks are on the exterior of the car, you have to take stock of the effect that environmental changes and external force have on the lock. This means that the lock can be blocked by dirt and debris if it is not regularly cleaned. Or on the flipside of things, the lock might be damaged due to an external collision.

2. Damaged Key

One of the main reasons why your car key might not be working is simply because the car key is damaged. When most people think of damaged keys, they tend to conjure up a picture of a broken key that is split into pieces. However, this is a grave misconception. A damaged key does not always have to be broken in place. If you take a look at the way car door locks work, you will come to understand this. The grooves in a key correspond to the internal mechanisms of the lock or the ignition that it is used for.

Keys are physical components, which means that each of these elements is prone to some wear and tear over time. Most people do not pay enough attention to their locks and keys to realize the effect that constant use might have on them. Once this is coupled with a lack of maintenance, it increases the probability of keys being damaged. If the grooves on the key are altered over time, and the key is no longer able to operate the internal mechanism of the lock, it is potentially damaged and this is probably one of the reasons why your car key is not working.

3. Faulty Ignition Cylinder

Your key is not only associated with your external car door locks, but it is also the tool that works in conjunction with the ignition. Car keys are not meant to exist alone. This means that for every key that exists, there is a lock or a mechanism that it is meant to function with. If your car key does not work when it is inserted into the ignition, it does not necessarily mean that your car key is faulty or damaged.

Sometimes, this is a symptom of a much larger issue, which might be damage to your car’s ignition. If you have not realized by now, cars are moving mechanical components. (Back in the day this would be called magic, but we can call it science and technology.) The point is, mechanical components are prone to wear and tear, so it is common for things to break down, and your ignition cylinder is no exception.

4. Worn Out Key Fob Batteries

Key Fob Replacement

Another reason that your car keys might not be working might be because the batteries in your key fob or keyless entry remote are out of juice. This is a common problem, but one that has a rather easy solution. Batteries run out after a certain period of time, so diagnosing this problem is relatively simple.

If you notice that your vehicle is not responding to the commands and signals being sent from your key fob, it is very likely that the batteries are dead. However, you should keep in mind that this is not the only reason your key fob might not be working. When you do realize that your car key is not working because of worn out key fob batteries, the simple solution is to find the right batteries and then replace them. Once this is done, your car key fob should be as good as new.

5. Internal Damage To Key Fob/Keyless Entry Remote

As I mentioned earlier, there are several different types of keys that each have their own unique uses and traits. The key fob depends on communication between a transmitter and a receiver, so if one of these components is damaged, it means that your car key will not work the way it was intended. If there is something wrong with the internal electronics of your car, or if there is damage to either the receiver or transmitter, your car key will not work.

Sometimes these elements can be damaged over time and manifest in the form of frayed wires etc. In other cases, damaged internal wiring can be as a result of external damage to your key fob or to your car itself. This could arise from something as simple as dropping your car keys and knocking the internal components of your fob out of alignment.

6. The Key Has Not Been Programmed

In a sense, even traditional keys have to be paired to cars. Although, technological advancements in the automotive industry have changed the way we view this pairing. The way car keys are paired now adds a layer of security that keeps cars much more secure than before. This is done through the use of transmitters, which are put in place to enhance the way car keys and cars interact, while simultaneously making car security harder to bypass.

Traditional keys do not have a programming issue, as it is something that only keyless entry remotes and transponder keys have to deal with. If your car key is not working with your vehicle, there is a chance that the key has not yet been programmed to work with your car. This is a common occurrence among people who replace their car key remotes or acquire duplicate car keys. They often forget that the transponder key and the key fob have to be programmed to communicate with your car. If you do not do this, the most you will be able to do with said key is unlock your car doors and your trunk.

7. Aftermarket Car Keys

Aftermarket car keys are essentially a much cheaper option that people often explore when they are looking to get replacement keys or spare car keys. It is crucial that you understand the dangers that aftermarket electronic car keys can pose, but if your car key is not working, that is probably the last thing on your mind.

If you buy an aftermarket car key for your vehicle and you neglect to reprogram it, you will most likely find that your car key is not working. Aftermarket items are usually the best place to get spare parts and other assorted automotive goods. However, you should keep in mind that most of these parts might not have been designed for your specific vehicle, so some additional work might have to be done. This is the reason why you should always make sure that your aftermarket car key is appropriately programmed and paired to your vehicle.

8. You Might Be Using A Copied Key

Car Key Copies

Car key duplicates are popular among drivers, and for good reason. It gives you the peace of mind knowing that your chances of being stuck in a car lockout are much more slim, simply because you have spare keys that you can utilize. It also gives you the luxury of being able to share your vehicle with members of your immediate family etc. However, many people do not realize that every consecutive car key duplication that is carried out reduces the integrity of the original key.

Forgive me if that sounds slightly complicated, but allow me to explain it in much simpler terms. Each time that a key gets duplicated, the duplicate moves further away from being identical to the original. This means that if you duplicate a duplicate car key, the version you are going to get will actually be different than the original. It might not sound like a big deal, but you need to understand that this will impact the way your car keys work.

In some scenarios, you will find that your car key is not working, simply because you might be using a duplicate car key that does not function the same as your original key. Obtaining a duplicate car key is a much cheaper option that getting a new key cut to code, but it is not always the best option, nor is it the most secure.

What To Do When Your Car Key Is Not Working

Ideally, the list above should help you determine why your car key is not working. However, determining the problem is only a small step towards arriving at the solution. I’ll leave you with some quick solutions that you can chase down:

1. If your physical key is damaged, then you should be looking to get a new key. For those that have traditional keys, a simple car key replacement will do the trick. However, if you have a transponder key, then you will need to have your replacement key programmed to your vehicle.

2. For damaged car door locks, you can reach out to either a professional locksmith or your car dealership for them to lend you assistance. In this case, they will either repair the damaged lock or install new car door locks. The latter might be a more expensive alternative.

3. Automotive locksmiths are well versed in dealing with faulty ignition cylinders, so if that is the reason why your car key is not working, make sure you reach out to one. They will advise you on whether or not the ignition can be salvaged and repaired, or whether they will have to replace the ignition cylinder entirely.

4. If your key fob batteries are worn out, you should simply replace them. To find the specific battery that your key fob uses, check out the owner’s manual for your vehicle. Some manuals will also give you some basic guidelines to help you change the batteries. If you cannot find your physical copy of the manual, you might be able to find it online via the manufacturer’s website. Key fob and car key remote batteries can be found at local hardware stores or a store that sells automotive parts.

5. Internal damage to the key fob or keyless entry remote is usually best handled by an automotive locksmith or your car dealership. Since they know how to navigate the internal workings of the fob, they will be able to help you get it repaired. If not, they will advise you on the proper key fob replacement.

6. Transponder key programming can be carried out by a reputable automotive locksmith or by your dealership. It is usually much cheaper to have this handled by a locksmith. The same concept applies to reprogramming aftermarket car keys. It all boils down to programming your vehicle to work with your key.

7. If you are using a duplicate key that is not longer viable, you will need to have a new replacement car key made. If you have a traditional key this will be very easy to accomplish. However, if you have a transponder key or a keyless entry remote, then you should always remember to have the replacement key programmed.


Car keys are an integral part of any drivers daily activities, so whenever your car key is not working, it can be a costly hassle. Taking the time to read through the points listed out above will help you properly diagnose the reason why your car key is not working. Hopefully, this will help you find the solution fairly quickly. Always remember that if you are unsure what to do, you should contact an automotive locksmith rather than tinkering around and potentially damaging your key, lock, or ignition.

Category: Automotive, Car Keys

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