How to replace the battery in a Mazda Key Fob?

by Phil Borges // in Car

Have you ever been in a scenario where your key fob battery has died, and the nearest auto shop is too far away to bring it? If so, read on for helpful tips on how to replace the battery in a Mazda Key Fob. 

How to replace the battery in a Mazda Key Fob?

Mazda key fob is your keyless entry into the car. It opens and starts your vehicle with a push of a button from outside without inserting it in the keyhole or fob pocket. This key fob is powered by a Lithium battery which is made to be replaced in due time. Knowing how to change the battery is very important to avoid unnecessary costs and inconvenience.

The Mazda key fob battery replacement is not a difficult task. The whole procedure will only take about 5 minutes or less with simple tools to use. Here's how to complete this project:

Step 1: Locate the small knob at the back of the key fob and press it down while sliding out the mechanical key.

Step 2: Use a tiny flat blade screwdriver to pry apart the two halves of the key fob. Be careful in doing this process as you may damage the key fob case if you exert too much pressure on it. You can wrap around a piece of tape or a thin fabric at the tip of the screwdriver to protect the casing when prying apart the key fob case.

Step 3: Remove the battery cover with your fingernails and then grab the small screwdriver to take out the old battery.

Step 4: Slide in the new battery and be sure to follow the correct battery orientation. As your guide, the side where the '+' sign should be facing up.

Step 5: Return the battery cap and reattach the key fob cover. Make sure that all sides are set correctly in place.

Step 6: Reinsert the mechanical back to its place and test out your newly replaced key fob battery to see if you have successfully replaced it.

Be sure to dispose of the old battery properly. These little batteries are dangerous as they contain hazardous materials.

Can you still use the key fob even when the battery is dead?

Don't worry! If your key fob battery dies, you can still get into the car and start its engine with just a few quick steps. It might be difficult for some people who are not accustomed to using these types of devices, but it's really quite simple once they know how.

Use the emergency key hidden in the key fob to unlock the doors of your Mazda. Insert the standard key in the lock and turn it to manually unlock the door on the driver's side. Get inside the car and place your foot on the car's brake pedal while pressing the key fob on against the push-button start. The vehicle will recognize the small chip in the key fob and will start the engine.

Don't forget to purchase a new battery replacement for your Mazda keyless entry system soon after the old battery dies. If you wait too long, it could drain the car's battery and leave you stranded without a ride. It is also a good idea to buy a spare battery and keep it in the glove compartment so you will always have a replacement on hand.

How often should you change the battery in the key fob?

You should change the battery in the key fob every three to four years or when the battery starts to drain. If your keyless entry remote is not working correctly, you need to replace its battery right away.

There are some signs that indicate there's a problem with the Mazda key fob battery, and these are:

  1. Weak signal strength - when you press the button on your key fob remote and nothing happens, this is an indicator that the battery needs replacing.
  2. The key fob does not lock or unlock the doors - there might be a problem with the circuit board, or it might be time to replace the battery.
  3. Problems programming - if you're having issues when trying to program your key fob, this is a sign that there's an issue with the battery.

If these problems sound familiar, make sure to get yourself a new Mazda Key Fob battery as soon as possible.


Changing the battery in the Mazda key fob is a great way to ensure that it doesn't stop working. It can save you from having to purchase another key fob or fix the one you have. Gaining knowledge on how to change the battery is also important so you can replace it yourself if needed. Just make sure to use the recommended battery, which is a CR2025, for this key fob for the best results.

About the author, Phil Borges

Phil Borges is a battery aficionado. He's written extensively about batteries, and he loves nothing more than discussing the latest innovations in the industry. He has a deep understanding of how batteries work, and he's always on the lookout for new ways to improve their performance.