Man Unlocking CX-5 With Key

How to Open the Mazda Key Fob and Replace a Dead Battery

Having remote start, push button start, and keyless entry on your vehicle can be very convenient, so much so that when they stop working, you’ll want them back up and running immediately. When these features stop working as they should, it could be that the battery simply needs replacing. While you can have these issues resolved at your local Mazda service center, you can also learn how to open the Mazda key fob and replace a dead key battery yourself at home! Here’s what you’ll need to get started:

  1. A replacement battery on hand (CR2025 battery)
  2. Your Mazda key fob
  3. A small flat head screwdriver with the head wrapped in tape to prevent scratches

Opening Your Mazda Key Fob

Whether you’re looking to learn how to open your Mazda6 key fob or a Mazda CX-5 key fob, you’ll be happy to know the process is very similar for all Mazda models from recent model years. Follow these steps to reveal the battery:

  1. Press the auxiliary key button on the back of your key fob in order to remove the metal auxiliary key
  2. With the metal key gone, you’ll notice a slot on either side of the key fob case. 
  3. Use the tape-wrapped flathead screwdriver to pry open the case, first on one side, and then on the other. Work gently.
  4. This should remove the case. Place the latter in an easily-visible spot where you won’t lose track of it.

Replacing Your Mazda Key Battery

Once you have your Mazda key fob opened, remove the dead battery and replace it with the new one to get your favorite features back up and running. This process should only take a moment:

  1. Remove the battery cap, and set it next to your key fob case.
  2. Your Mazda key fob battery should be fully exposed. Remove it, being careful not to damage the small rubber ring that it sits upon.
  3. If you scratched or damaged the rubber ring, it’s important to replace this component before moving on.
  4. With the ring in place, take your new replacement battery and set it in its place in the key fob. The positive (+) side should be up, facing you.
  5. Return the battery cover to its proper place, and then reattach both sides of the key fob case. Press until you hear them click into place.

Get Service Assistance at Findlay Mazda

Once you learn how to change the battery in a Mazda key fob, you’re set to do so at home! If you don’t have time to replace your Mazda key fob battery yourself, or simply want to make sure that it’s done right the first time, reach out to Findlay Mazda to schedule service. Check out our available service specials to help you save more! Contact Findlay Mazda with any questions.

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