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Tips for looking after your car keys

| Insurance

A lot of us rely on our cars to take us from A to B - but you’re not going to get very far without your keys. These days, many vehicles have keyless technology, meaning you can lock, unlock, and even start the ignition, all at the touch of a button. The modern car key fob is a smart piece of kit, so it’s important that you know how to look after it.

To find out how you can take care of your fob, including how to change the battery and what to do if it comes into contact with water, keep reading.

How to change a car key battery

If you notice that your car key fob only opens the doors now and again, or it does not lock or unlock the car at all, this could be a tell-tale sign that the fob battery needs replacing. Even though you may still be able to use the manual key function of the fob to secure your vehicle, the automatic lock and unlock feature can be extremely useful, so it’s worth knowing how to change the battery inside the fob when it needs replacing.

The good news is, changing the battery inside a car key fob is quick and easy for you to do at home. However, if you'd prefer, you could take it to your local garage or car dealership for assistance.

To determine that it is definitely the battery that’s the problem, you can first check if the manual locks on the car still work. If they don’t, it could be an issue with the vehicle’s locking mechanism rather than the car key or the fob battery. If you have a spare fob for your car, you could try locking and unlocking the car with this too. If it works, you can assume that the battery in the other one is the problem.

Once you’ve established that the battery needs replacing, you’ll need to purchase a new one. In most cases, car key batteries are round and flat like a coin. To make sure that you buy the right type and size of battery, open up the fob to look at the original battery.

You should be able to lift up the part of the fob where the battery is situated by simply using your finger, but you can also do this using a flathead screwdriver. After carefully opening up the fob casing, you should be able to see the battery inside. You can then remove the battery using your finger, or you could turn the fob upside down, give it a gentle tap and let the battery fall out into the palm of your hand.

On one side of the battery, you should be able to see a code. In most cases, this code begins with two letters, such as CR, and is followed by some numbers. You should make a note of this code or take a photo of it when purchasing a new battery for your car key fob. If you are struggling to find the code, you should be able to find this information in your car manual. You will be able to purchase a replacement fob battery from specialist retailers such as Halfords, as well as online from sites like Amazon.

When you’ve got a replacement battery, simply slot it back into the fob, clip the casing back together and your key will be good to go.


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How long do car key batteries last?

You probably use your car key fob a lot more than you think. Aside from using it to lock and unlock your vehicle, it’s likely your fob offers a variety of additional features too. For example, you might also use it to open and close the boot, and you might even be able to use it to start the ignition.

The truth is, you rely on your car key for a lot, so it’s no surprise that the battery inside it will not last forever. With this in mind, you could find that your car key battery lasts around three to four years before it needs replacing.

How to dry out a car key fob

Whether you accidentally drop it in a puddle, spill a drink over it or it ends up in your washing machine by mistake, you might panic if your key fob gets wet. There’s no denying that water, and other types of fluid, can be bad news for your key fob. It has the potential to damage the internal electronics of the fob, and even stop it from working altogether. So, if this happens, it’s important that you know exactly what you can do to help dry out your car key fob.

First, grab something to dry the fob with, such as a kitchen towel or even an old rag. It’s a good idea to turn the fob so that the buttons are facing downwards, giving it a gentle yet firm shake to remove as much excess water as possible. You may be concerned that you might get a shock from the wet car fob. However, it is highly unlikely that this would happen, but it is still advised to dry off the fob as soon as possible using a towel or cloth.

Once you’ve dried it off as much as you can, you should remove the battery from the fob, following the instructions outlined in the section above. After you’ve taken the battery out, don’t replace it with a new one just yet. It’s a good idea to let the inside of the fob dry out for a couple of days, especially as this is where the transmitter, and in some cases, a chip which controls the vehicle’s ignition system are located.

To help the fob dry out as much as possible, you could place it in a plastic bag with some packets of silica gel. These small sachets are often included when you buy a new pair of shoes or a handbag, so you might want to check if you have any of these lying around your home. If you don’t, you can simply leave your fob to air dry in a warm room.

When you’re drying out your key fob, don’t be tempted to use a hair dryer or place it on a radiator to speed up the process. You should also avoid placing it into a container of rice - a popular but questionable trick some people use to dry out mobile phones when they come into contact with water. While some believe rice can help absorb moisture, it can actually introduce moist starch particles, which will only make the problem worse.

Once the inside of the fob is dry, you can replace the battery and try it out to see if it works. If it doesn’t work, you will need to get a replacement key fob. In this case, it’s worth checking your car insurance policy to see if you’re covered for key protection, as you may be able to process a claim for the damaged fob and request a new one from your car dealership.

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