Having a key fob for your car can sure make life easier in a lot of ways. With a key fob, it's a cinch to lock, unlock, or even potentially start your car. Just like other electronic devices though, sometimes the battery in your key fob might need a replacement. Luckily, it's relatively simple to change the battery in your key fob on your own. 

Read on as we answer the question "How do you change the battery in a key fob?" through easy-to-follow directions. 

Signs That You Might Need To Change the Battery in Your Key Fob


While sometimes the batteries in key fobs unexpectedly die, there are often some warning signs that suggest the battery power is waning. Here are some signs to watch out for indicating it might be time for you to replace your key fob battery: 

  • If the buttons on your key fob no longer respond when you touch them.
  • If you notice the distance that you have to stand from your vehicle to use the key fob has lessened. For instance, your vehicle might normally have a 50 feet range for the fob, but you notice suddenly that you need to be closer to 20 feet away for the key fob buttons to work. 
  • If a warning light on your car dashboard suggests that there's a problem with a low battery or the charging system .

How Do You Change the Battery in a Key Fob?

Key fobs operate through a wireless connection to your car. A battery inside of the key fob powers this wireless connectivity. Key fob batteries typically last between two to five years, although the exact time they endure can vary based on factors like how often you use the fob and the type of battery they operate on. 

Let's take a closer look at the exact steps you can use to change the battery in your key fob so you can once again control your car with ease: 

1. See If You Can Determine the Battery Type in Advance

Some key fob manufacturers print an icon on the exterior of the fob indicating the size and brand of battery that it uses. If your key fob has one of these icons, then you can purchase the exact battery type that the fob needs before you open up the fob and extract the old batteries. Some common key fob brands include Energizer, Duracell, and Panasonic. 

2. Find the Notch Where the Fob Opens

Many key fobs have a clamshell-like design, with two halves that can open and close together. Look for a notch along the seams of the key fob showing where you can pry the fob halves part. You might find this notch along the top or the bottom of the fob. If you can't see a notch, you'll likely need to separate the halves at the connection point where the metal key emerges from. 

3. Carefully Take the Fob Halves Apart

Use a tiny screwdriver with a flat edge to gently separate the two halves of the key fob. You might also be able to use a fingernail instead of a screwdriver as long as you're extra careful. The key fob will part down the middle to reveal the battery inside, likely a small circular one. If you weren't able to determine the battery type that your key fob uses prior to opening the fob, you can now see the exact size and brand that you need to purchase. 

4. Determine How To Insert the Battery

Examine the battery orientation so that you know where both the positive and negative ends of the battery should go. It's very important to insert the new battery with the same orientation as the old one. 

5. Remove and Replace the Battery

Most batteries inside of a key fob will come out when you press a finger down on the center of the battery. If that doesn't work, use your flat-edge screwdriver to carefully remove the battery. You can then put the new battery inside the fob. 

6. Close the Fob and Check That It Works

Put the fob back together by aligning the edges of both halves and snapping it closed. Check to make sure that all the buttons now operate as they should.

What Do You Do If the Key Fob Battery Dies Without Warning?

Although many key fobs will indicate ahead of time when their battery power starts to wane, sometimes a key fob battery might stop working without warning. The good news is that most key fobs also contain a regular metal key that you can use to manually lock or unlock your car doors and start your engine. If you have your owner's manual on hand, you can consult that for more specific instructions about using your vehicle without its key fob. 

In general, the following procedure can work if you're out and about when your key fob unexpectedly dies: 

  1. Extract the metal key from the fob, usually by holding down a button that causes the key to pop out. 
  2. Unlock your car door with the metal key. Depending on your vehicle type and settings, this might cause your car's alarm to activate, but luckily, you can deactivate it by inserting the metal key into the ignition. 
  3. If you normally use your key fob to start your vehicle, you'll likely need to pull out the start-stop button in order to access the ignition and put in your key. Be sure to first have your vehicle set to park while your foot holds down the brake pedal. 
  4. Turn the key to activate the car's engine. If you had to remove a stop-start button to find the ignition, be sure to store the button in a secure location until you've fixed your key fob. 

Did you find these instructions on changing the battery in your car key fob useful? Let us know in the comments section of this blog. If you're still having trouble with your key fob, feel free to book an appointment at our service center. We'd also be happy to help you sell or trade in your current car or get a new or used vehicle

Image by Reinhart Julian is licensed by Unsplash License

Categories: Service
Tags: key fob