7 Small Changes That Will Make An Enormous Difference To Your Mazda 6 Key Fob Changing the Battery in Your Mazda 3 Key Fob

There's nothing more frustrating than returning to your vehicle after a long and tiring day and realizing that the key fob battery is dead. This is a simple solution that can be accomplished at a big box retailer or hardware store.

A spare key fob for your Mazda 3 is an inexpensive option to not have to take it by a dealership to let them reprogram the keys.

Battery Replacement

Change the battery in your Mazda 3 key fob is an easy task that you can do at home. But, it is best to replace the battery if it goes out of service, or if the key fob displays a message in the multi-information display that reads, "Low key fob battery. Replace battery."

To open the key fob's casing it requires a tape-wrapped flathead screwdriver as well as some patience. Find a gap or notch in the bottom metal part of your Mazda 3's key fob and then insert the tip of the screwdriver in it to pry off the lower portion. Repeat this step for the top metal piece but be careful not to scratch the rubber ring at the bottom of the key fob's case.

There is a slot on the opposite side of the case that contains the battery. Start on the other side of the case, and then gently open it. Remove the old CR2025 and replace it with a new one, making sure that you place it face-up to ensure the correct the polarity. Finally, place the cap back on and reconnect both sides of the key fob's case. Continue pressing until you hear them click.

After you've replaced the battery, test the fob to ensure it works by locking and unlocking your doors. If everything looks good then you're able to use the Mazda 3's remote features on the road again!

Pairing Issues

If your key fob stop working all of a sudden it could be because the transmitter inside your car is damaged. This typically requires the assistance of a professional for repair and may require a new replacement key fob.

If you have tried replacing the battery and reprogramming the key fob, but this isn't solving the issue it is possible that the chip inside the key fob may be defective. This can happen if your keyfob was dropped or exposed to saltwater or was touched by dirty fingers.

To identify the issue, you will need to find a small "key" built into the edge of the fob that allows you to open it up and take out the circuit board. You can then examine the chip for damage or corrosion. It is best to use a clean paper towel to avoid damaging the microchip.

You may also take a close look at the battery connector's terminals and examine if they're damaged or cracked. If this is the case, then carefully soldering them back in place can usually restore the function of the key fob. You can also examine the buttons for damage or wear. If the buttons are loose, they can easily be soldered back into place in the event that the button has actually snapped off.

Interference Signals

There are few things more frustrating than trying to get the engine started in your car and then seeing the message "No Fob Detected". It happens at the worst occasions, such as when you're running late to work or when you have to pick up your children from daycare/school. There are some things you can try to figure out the root of the issue.

mazda rx8 key fob can disrupt the remote key fob signal from the vehicle making it unable to work correctly. It can be caused by objects such as weather conditions, buildings and transmitters using the same frequency. Interference can also occur when you have an aftermarket device installed in the vehicle that transmits on the same frequency as the key fob.

In addition, if the key fob is exposed to salt or water water it may be damaged. The rubber seals on the electronic chip may be shattered by water, especially when it is submerged for an extended period of time such as in a pool or at the beach. This could cause the chip to stop working and require replacement of the key fob. If you have a key that can be programmed to work, you can clean it with isopropyl or electronic cleaners to restore its function. If this doesn't help the chip, it's likely fried and will need to be replaced.

Locking or Unlocking the Doors

The buttons on the key fob transmit electronic signals to a solenoid within the car. It transforms the signal into a mechanical action that locks and unlocks the doors. If the door lock isn't working, it could be a solenoid issue that requires some analysis with the help of an expert repair shop for autos.


A dead 12 volt battery can also stop the fob from functioning correctly. This can occur if your battery is not charged or if your contacts get corrosion-prone. The problem can be addressed in minutes with a new battery.

If the key fob won't work after you change the battery or try to reprogram it, the issue might be related to the receiver module. The device receives radio frequency signals from the key fob and interprets them to control the functions of the vehicle. If it malfunctions it could cost a lot to repair.

To determine if this is correct, place your spare key in the key slot. Then, turn the ignition ON. Press the key fob twice within 10 seconds, but without taking it out. The Mazda 3 system synchronizes the key with the vehicle and you can use it as your primary remote for driving. This allows you to program up three keys.