Changing the Battery in Your Mazda 3 Key Fob

There's nothing more frustrating than stepping into your vehicle after a long day and realizing that the key fob battery is dead. Fortunately, it is simple to fix it with simple battery replacement from the hardware store or big box retailer.

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

Battery Replacement

Removing the battery from your mazda 2 key replacement 3 key fob is an easy process that can do at home. But, it is best to replace the battery when it goes out of service, or if the key fob displays a message on the multi-information display, "Low key fob battery. Replace battery."

To open the case of your key fob you'll need a tape-wrapped flathead screwdriver as well as some patience. Find a gap or notch in the bottom part of the metal of the Mazda 3's key fob, and then insert the tip of the screwdriver to cut off the lower half. Repeat this process for the top metal piece however, be careful not to scratch the rubber ring at bottom of the key fob's case.

When the fob case is opened, you'll notice the slots on either side of the case, which houses the battery. Use the flathead screwdriver with tape to gently the case open, beginning at one end and moving to the next. Remove the old battery, and put in a new CR2025 ensure that it's facing upwards to ensure proper orientation. Put the cap of the battery on again and attach both sides of your key fob case by pressing until they click.

Once you've replaced your battery Check the fob to verify that it's working by locking and unlocking your doors. If everything looks good, your mazda key Fob 3 remote features can be used again.

Pairing Issues

This could mean that the transmitter in your car may have been damaged. This is usually a matter for a professional, and you will require a brand new key fob.

If you have tried replacing the battery and programming the key fob, but this did not resolve the issue it could be that the chip inside the key fob could be faulty. This can happen if the key fob has been dropped on hard surfaces and exposed to salt water, or even touched by dirty hands.

You'll need to locate an extremely small "key" that is inserted into the seam, to take off the circuit board and determine the issue. You will then be able check for any corrosion or damage on the electronic chip. To avoid damaging the chip, it is best to use a fresh paper towel.

It is also possible to inspect the battery connector terminals to check if they're damaged or cracked. If this is the case, carefully soldering them back in place can usually restore the function of the key fob. It is also possible to check the buttons for wear or damage. If the buttons are loose, they can be soldered back into place and also if the button has actually snapped off.

Interference Signals

Few things are more annoying than staring at an "No Fob Detected" message when trying to start your car. This usually occurs at the most unpopular moments, like when you are late for work or when you are picking up your children from school/daycare. There are some things you could do to find out the root of the issue.

Interference signals can interfere with the remote key fob signal coming from the vehicle which causes it to not work properly. This can be caused by things such as buildings, weather conditions and transmitters that operate on the same frequency. Interference can also occur if you install aftermarket equipment in your vehicle that transmits at the same frequency as the key fob.

In addition, if your key fob is exposed to salt or water waters, it could be damaged. The rubber seals on the electronic chip can be penetrated by water, particularly when it is submerged over long periods of time, like in a pool or at the beach. This could cause the chip to stop working and may require replacement of the key fob. If you have a key that has the ability to be programmed to work, you can clean it using electronic cleaners or isopropyl to restore its function. If this does nothing will be able to fix the issue, then the chip has been damaged and needs to be replaced.

Locking/Unlocking of the Doors

The buttons on the key fob send electronic signals to a solenoid inside the car, which transforms the signal into a mechanical action that locks and unlocks doors. If the door lock isn't working, the issue could be a solenoid malfunction that requires investigation with the assistance of an expert auto repair shop.

A dead 12 volt can also prevent the fob from functioning effectively. This happens when the battery is unable to charge or if the contactors get corroded and stop transferring electricity. The good news is that a new battery can resolve this issue in a matter of minutes.

The receiver module could be the reason why the key fob won't work after you replace the battery or reprogram the device. This device detects radio frequency signals sent by the key fob to control the vehicle. If it breaks down, it can be expensive to repair.

To test if this is true, put your spare key in the key slot. Then, turn the ignition on. Press the key fob button three times within 10 seconds, without removing it. The Mazda 3 system synchronizes the key to the vehicle and you can use it as your primary driving remote. You can program up to three keys in this manner.