Changing the Battery in Your Mazda 3 Key Fob

There is nothing more frustrating than getting in your car after a long work day and finding that the key fob battery is dead. This is a simple fix that is easily done at a big box retailer or hardware store.

A spare key fob for your Mazda 3 is an inexpensive alternative to not having to take it to a dealership to have them re-program your keys.

Battery Replacement

Removing the battery from your Mazda 3 key fob is an easy process that can perform at home. It is recommended to replace it if the battery goes out or if you see a message saying "Low keyfob battery" on the multi-information display. Replace battery."

To open the case of your key fob it requires a tape-wrapped flathead screwdriver and some patience. The flathead screwdriver's tip in a notch, or gap on the bottom of the metal of the Mazda 3 key fob to pry the lower half off. Repeat the process for the top metal piece but be careful not to damage the rubber ring that is on the bottom of the case.

Once the fob's case is open, you'll be able to see a slot on either side of the case that houses the battery. Use the tape-wrapped flathead screwdriver to gently pry the case open, beginning on one side before moving to the other. Remove the old battery, and put in the new CR2025, making sure that it's facing upwards to ensure the correct polarity. Then, put the cap back on and then reattach both sides of the key fob case. Keep pressing until you can hear them click.

After replacing the battery after replacing the battery, lock and unlock your doors to confirm whether the fob is working. If everything looks good, your mazda 3 key fob replacement 3 remote features can be used again.

Pairing Issues

If your key fob has stopped functioning suddenly it could be because the transmitter in the car has been damaged. It's usually a task to a professional and you will require a brand new key fob.

If you've tried to replace the battery and reprogram the key fob, but it hasn't worked then the chip in the key fob might be defective. This can happen if the keyfob has been dropped or exposed to saltwater or handled by dirty fingers.

You'll need the tiny "key", which is inserted into the seam, to take off the circuit board to identify the issue. You can then check the electronic chip for corrosion or damage. It is best to use a clean towel to prevent damaging the microchip.

If you're unsure you are not sure, you can check the battery connector terminals for cracks, or breaks. If this is the situation it is possible to solder the terminals back to their original position will usually bring back functionality to the key fob. In the same way, you can examine the buttons to determine whether they are worn out or damaged. If the buttons are loose, they can easily be re-soldered and also if the button is physically snapped off.

Interference Signals

There's nothing more difficult than trying to start your car and seeing the message "No Fob Detected". It happens at the worst occasions, such as when you're late for work or when you have to pick up your children from school or daycare. There are some things you could try to figure out what's causing the issue.

Interference signals can interfere with the remote key fob's signal to the vehicle which causes it to not function properly. It can be caused by objects such as weather conditions, buildings and transmitters using the same frequency. Interference can occur if your vehicle has aftermarket equipment that transmits at the same frequency as your key fob.

Additionally, if the key fob is exposed to salt or water waters, it could be damaged. The rubber seals on the electronic chip could be damaged by water, especially when it is submerged over long periods of time, such as in a pool or at the beach. The chip can stop working and may require replacement of the keyfob. If you have a key that can be programmed, you can clean it with isopropyl and electronic cleaners to bring it back to its original function. If this doesn't help will be able to fix the issue, then the chip has burned out and needs to be replaced.

Locking/Unlocking of the Doors

The key fob's buttons send electronic signals to a solenoid within the car, which converts the signal into a mechanical action that locks and unlocks doors. If the door lock isn't functioning, the issue could be due to a solenoid problem that requires investigation by an expert auto repair shop.

A dead 12 volt battery could also stop the fob from functioning properly. This could happen if the battery's charge is lost or the contacts become corroded, and stop transferring electricity. The good news is that a new battery can fix this issue in just minutes.

The receiver module could be the problem if the key fob won't work after you replace batteries or reprogram the device. The device receives radio frequency signals from the key fob and interprets them into controlling the vehicle's functions. It can be a costly repair if it is damaged.

To determine whether this is the case, start by inserting your spare key into the key slot and setting the ignition to ON. Press the key fob button two times within 10 seconds without taking it. The Mazda 3 system will now connect the key to the vehicle and you can then use it as your primary remote for driving. This allows you to program up to three keys.