How To Change the Battery in a Mazda Key Fob

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Key fobs are convenient and being used everywhere, from vehicles to schools to businesses. They allow users quick access to whatever it is that the key fob opens. But what happens when a key fob stops working? For your Mazda, do you need to take the key fob to a dealer and pay to have it fixed, even if you suspect the issue is the battery? If you’re experiencing a Mazda key fob that no longer works, and you think it has a dead battery, you can change the battery yourself and save time and money. Our service team at Hiley Mazda of Fort Worth will be more than happy to help you out if you schedule a Mazda service appointment today, or If you have any questions give us a call at (817) 663-7404. 

Tools of the Trade

When your KEY dashboard warning light stays on even after the engine is off, or if your key fob indicator light no longer flashes when you try to use it, your Mazda key fob battery is more than likely dead and needs to be replaced. Although it’s recommended that you visit a certified Mazda dealer and work with a technician to avoid damaging your key fob, you can go through the steps on your own. Before you get started, you will need a few simple tools to get the job done. For a 2016 or newer Mazda key fob, you’ll need the following:

• The Mazda key fob with the suspected dead battery.
• A flathead screwdriver wrapped in tape.
• A battery to replace the dead one.

Once you have gathered these tools and found a good light to work under, you’re ready to open up your Mazda key fob and change that dead battery.

Changing the Battery in a Mazda Key Fob

Your owner’s manual is the best reference for the most current steps in replacing your key fob battery. Here are the steps as outlined for the 2016 model year. Although most model years don’t vary much, you will still want to double-check before cracking open your key fob. Follow these steps carefully:

1. Remove the auxiliary key from the key fob by pressing the little knob on the back of the fob. The auxiliary key is hidden away in the key fob to be available if you experience a broken or dead key fob. This auxiliary key will manually open the door to your Mazda. It will also start the vehicle, if necessary.
2. Take the flathead screwdriver you have wrapped in tape and insert it into the opening where you removed the auxiliary key. Gently twist the screwdriver toward the opposite end to the opening in order to loosen the cover of the key fob. After you have loosened the cover, put the screwdriver into the gap that opened up on the outside of the key fob. Then slide the screwdriver down that gap to loosen the cover even more until you have safely removed it.
3. Now that you have the cover off, remove the battery cap and then the battery itself. If the little rubber ring inside your Mazda key fob comes off during this step, make sure that it does not get damaged or scratched.
4. If the little rubber ring does come off, you should attach it before moving on to the next step.
5. Grab the new battery and position it with the positive end facing the top of the Mazda key fob and then gently insert it into the key fob.
6. Put the battery cap back on.
7. Replace the key fob cover by carefully snapping it back into place.
8. Put the auxiliary key back into the hidden spot of your Mazda key fob.

These steps seem simple enough, but again, it’s recommended that you work with a certified technician to guarantee that you don’t do any damage to your Mazda key fob. They will also be able to help you if changing the battery doesn’t fix the issue.

What if It’s Not a Dead Battery?

After taking the time to replace the battery in your Mazda key fob, if it still doesn’t work to open your vehicle, then it’s time to schedule an appointment with a certified technician so that they can further delve into what may be causing the issue. In the meantime, in order to unlock and drive your Mazda, you’ll need to use the auxiliary key located within the key fob.

Using the Auxiliary Key

Don’t find yourself stuck due to a broken Mazda key fob! Every Mazda key fob comes with an auxiliary key hidden within the fob itself. Here’s how to use it:

1. Press and hold the little button on the underside of the key fob to release the auxiliary key.
2. Grab the end that has a tiny loop on it at the top of the fob.
3. Gently pull the auxiliary key out of its housing.

After completing these steps, you can now use the auxiliary key to unlock the driver’s side door and start your vehicle. To start your Mazda:

1. Put the shifter into Park (P) or Neutral (N) before starting.
2. Press the brake pedal down.
3. The engine start button should flash green at this point, indicating that it’s ready.
4. Grab your key fob and touch the push-button start with the backside of the key fob.
5. Once the green engine starts light stops flashing and stays lit, you can press the push-button start as if you usually would star your vehicle.
6. Let your car idle for 10 seconds before taking it out of Park (P) or Neutral (N).

Mazda knows that it’s essential to have a backup, just if the key fob fails. Once you’re up and running, take your vehicle and the broken key fob to a Mazda service center as soon as possible.

What if I Lose My Mazda Key Fob?

Losing a key fob can be a horrible experience, but there is a light at the end of the tunnel. If you simply can’t find your Mazda key fob, you will need to contact a Mazda dealership to obtain a new one. If you still have the other key fob, this will be slightly easier and less expensive because programming might be easier. The dealership will need to program a new key fob to work with your Mazda vehicle to get you back on the road.

If you need help changing the battery in your Mazda key fob, figuring out what’s wrong with your broken fob, or even need to replace a lost fob, reach out to us at Hiley Mazda of Fort Worth. Our friendly, knowledgeable service staff are here to help you with all your Mazda needs.