How To Change The Car Key Battery

How To Change The Car Key Battery

Replacing a key fob is more expensive than simply replacing the battery, so it’s worth checking if the problem can be resolved with a new battery. What to do when the key fob’s battery runs out? How to change the car key battery?

  1. Open up the key fob. 
  2. Find out what battery type you need. 
  3. Remove the battery.
  4. Add new battery with positive and negative terminals placed correctly.

If your remote key fob has stopped remotely opening the doors, it is possible that the battery needs to be replaced.

Similarly, if it only opens the doors every now and then, the battery may be getting weak, in which case a replacement is also a good idea so it can do its job properly.

The good news is, key fob battery replacement is simple. Here’s a step-by-step guide for how to change the battery in your key fob.

Signs You Need Key Fob Battery Replacement

Signs You Need Key Fob Battery Replacement

Even if your key fob appears to be working appropriately, there are some small irregularities that can occur when your battery is on its end.

It’s likely that you may be dealing with these issues without even realizing it. But these small inconveniences could eventually lead to some serious consequences down the line and no one wants that happening

  • The distance at which the key fob works is reduced.
  • You often have to press the lock/unlock buttons several times.
  • Key fob doesn’t work at all but the car battery is fine.

If you’re having any of the symptoms that we mentioned above, you need to change the battery in the key fob.

[Related Article: What Are The Reasons My Car Battery Won’t Charge]

Changing Car Key Battery

Changing Car Key Battery

Here’s how to change the battery in the key fob.

Look For The Seam

Look For The Seam

Most key fobs open in a clamshell fashion, where two halves snap together. There will be a seam where you can split the two halves—sometimes there will even be a notch at that seam.

If your car still requires you to put the key in the ignition switch, make sure you don’t hang anything from that keyring other than the fob; the weight of your other keys can wear down the ignition cylinder, which is potentially hazardous.

Pry The Key Fob Open

When it comes to how to change the battery in your key fob, you’ll only need one tool. Using a small, thin flat-bladed screwdriver (or, sometimes, a sturdy fingernail), pry apart the two halves gently to open the fob down the middle.

Most cars with key fobs and transponder keys won’t let you lock your keys inside the car, but you need to be prepared just in case the worst-case scenario happens. (By the way—if you have a habit of losing your keys, this key finder can help you out).

Find Out The Battery Type

Find Out The Battery Type

On some key fobs, the battery type will be printed on the outside. This way, you can go to the store and select your battery before you need to open up the fob.

Three of the most popular brands of key fob batteries are Duracell, Energizer, and Panasonic.

If the battery type isn’t printed, take the old battery to the store so you can get the exact same one.

Remember The Battery Orientation

Remember The Battery Orientation

The battery will usually resemble a small coin, be marked with the battery size, and have a plus and minus sign.

Note carefully which direction the battery is oriented. Once you’ve purchased a new battery of the same size, it will need to go in the same way.

Remove Old Battery And Install New One

Usually, the battery will pop out of its place with the press of a finger—if you’re having trouble, that flat-bladed screwdriver will help. Insert the new battery with the same orientation of plus and minus signs.

Test The Key Fob

Test The Key Fob

Assembly is the reverse of disassembly—snap the fob back together and test out the buttons. Everything should be as good as new!

Now that you know how to change the battery in your key fob, learn about the unusual car features you might not know you have.

If it doesn’t work then the problem may be wasn’t with the key fob. The problem may be with the battery.

If the battery is left out of the fob for too long, in some cases this can make the fob stop communicating with the car. At this point, it’ll need reprogramming, which may require specialist help.

[Related Article: How To Change A Car Battery]

Optional: Visit A Professional

Chances are, for some of you, this will be too much of a bother. More so, newer cars have key fobs that have a specific kind of battery. Changing the battery will require a professional.

If your car is still under warranty, I highly suggest taking the key to a licensed servicer. If not, consider taking your key fob to a professional.

Although their fee may cost more than simply buying a new battery, you are saving yourself from the hustle of replacing it.

Related Questions And Other FAQs

Can You Start A Car With A Dead Key Fob

In most cars, the security (immobilizer) chip inside the fob can start the car without a battery, but only from a short distance, so even if the fob’s battery is dead, it should still start the car. This key can open the driver’s door if the fob battery is dead or if the car’s main battery is discharged.

Does It Need Programming Afterward

If you change a key battery and the central locking stops working afterward, there is normally a simple reset procedure. Other keys just need the ignition turned on and the button held for five seconds.

What Happens If Battery Is Left Out Of Key Fob

If the battery is left out of the fob for too long, in some cases this can make the fob stop communicating with the car. At this point, it will need reprogramming, which may require specialist help. If your car key seems to be quickly using up batteries, get the advice of a specialist as this may suggest you need a new fob.

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