Car Won’t start – Do I need a Car Key Battery?

Ford Fiesta smart key

If your car won’t start, we want to to try and help you. We get lots of calls about cars not starting and although we’re not mechanics, we do know a lot about car keys. So we can say with some confidence if your key is at fault. But before we look at your car problem, lets look at car keys generally so you understand the problem more. 

Which Type of key do you have?

There are two types of car key, the first type is one that has a blade, like the photo above. To start your car you put it into the ignition lock and turn it. We call this a traditional car key, or non-smart key

This type of key has a chip inside the key that is recognised when you turn the car ignition on. It happens in a second and we doubt you’ve ever have noticed it, but it happens. This is NOT the same as the battery.

If your car won’t start and you have this type of non-smart key, then a key battery will not help you. We know this for sure, so don’t waste any more time or money. 

There are only a very small number of cars that use non-smart keys but still need a car key battery to let the car start. They are old obscure Kia and Hyunadai cars and it’s very unlikely you have one of them. 

If you have one of these non-smart keys, and your car won’t start, then it could be the transponder chip at fault. However, we won’t be covering that in this article, so click here to find out more about problems with Transponder chips. 

Lets move on to give you some help.

Car won't start - is it your smart key?

Ford Smart Key

The other type of key we see doesn’t have a blade to put into the lock. These keys are called a several names, according to the manufacturer. 

They are called ‘smart’ keys, ‘intelligent’ keys or even ‘proximity’ keys.  For this article we’ll call them smart keys, although we do wonder the if the idea is very smart at all!

Suzuki Smart Key

The important thing with smart keys is that you need a really good quality car key battery. We’ve written about this at length so won’t repeat it all again, but click here to find out more. 

If your car key battery needs replacing in a smart key, there’s a good chance your car will not start.

There is a simple reason for this, so let’s look at why. 

New Technology but car won't start!

The thing that makes your car key smart, is that instead of you having to put the key into the lock and turn it, you just press a button. The manufacturer thought it would be a good idea to remove the lock, and replace it with a button.

spare car key in lincoln

We agree that this is a nice thing when it works. The downside is that cars are easier to steal

However, we’ll ignore this for now and concentrate on how to know if you need a key battery, to get your car up and running. 

With a smart key you still have a chip in the key. Remember that with a non-smart key, this chip gets checked when you turn the ignition on. Well your smart key does the same thing. When you press the start button, the car looks for your car key. If it can’t sense your car key, this may be a reason your car won’t start. 

Did you ignore the warnings?

When your car key battery starts to get weak, it gets harder for the car to sense your car key. It will help you by showing you a message to change your car key. This photo is from a Ford, but other manufacturers do a similar thing. 

car key battery change

You can probably get away with driving around like this for weeks, maybe months. However, eventually the car will no longer be able to sense the key and the car will not start. There are ways to use the car still, and we’ll cover this in future articles. However for now you need a new car key battery. 

Will I always get a message?

All of the manufacturers are different, however this is the general rule.

If your car does not see the car key, you’ll get a message telling you so. 

Car won't start
new car key
new car key battery

My car is turning over, but won't start

If your car won’t start, but is trying to, it’s not the smart key. If the car doesn’t see the key, it will normally sit there and do nothing. On many of the manufacturers, if it doesn’t see the key, it won’t even bring the dashboard lights on. So if it’s all behaving normally, the dashboard looks normal but it won’t start, the key is not to blame. 

I broke down driving and now my car won't start

This is not the fault of the key. If you were driving along quite happiy and then cut out, we know for sure that it isn’t the fault of the key. In fact you can start the car and then take them out of the car and you can still drive it. We know this because of the amount of drivers who leave the keys on the roof and drive off!

Once the car sees the car key, it doesn’t need to keep checking that it is still in the car. 

Can you change my car key battery?

Yes, if your close to us and need yout car key battery changed, just drop in. We’re based on Chieftain Way, just off Tritton Rd in Lincoln. Click here to find us on Google Maps.

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