Changing the Battery in Your Mazda 3 Key Fob

There's nothing more frustrating than getting to your car after a long day, and finding that the key fob battery is dead. This is a straightforward fix that can be found at a big box retailer or at a hardware store.

Adding a spare key fob to your Mazda 3 can be an affordable solution to free yourself from having to be transported to a dealership and having them reprogram your keys.

Battery Replacement

Change the battery in your mazda 2 key replacement 3 key fob is a simple process that you can do at home. It is recommended to replace it if the battery goes out or remote if you notice a message stating "Low keyfob battery" on the multi-information display. Replace battery."

To open the case of your key fob you'll need a tape-wrapped flathead screwdriver as well as some patience. Put the flathead screwdriver's tip in a notch or gap on the bottom metal of the Mazda 3 key fob to remove the lower part. Repeat this procedure for the top portion of the metal however, be careful not to damage the rubber ring at bottom of the key fob's case.

There's a slot the opposite side of the case that houses the battery. Start on one side of the case and gently lift it up. Remove the old CR2025 and replace it with a brand new one, ensuring that you put it on its face to ensure the correct polarity. Then, put the cap back on and reconnect both sides of the key fob case, pressing until you can hear them click.

Once you've replaced your battery check the fob to make sure it is working by locking and unlocking your doors. If everything appears to be working then you can begin using your mazda key 3's remote features for the first time!

Pairing Issues

This could mean that the transmitter in your car is damaged. This is usually a matter of an expert repair and will likely require a replacement key fob.

If you've tried replacing the battery and reprogramming the key fob, but isn't solving the issue it is possible that the chip inside the key fob could be defective. This can occur if the key fob has been dropped on hard surfaces or exposed to salt water or even touched by dirty hands.

To determine the cause of the issue, you will need to find a small "key" embedded in the seam of the fob which allows you to open it and take out the circuit board. You can then examine the chip for damage or corrosion. To avoid damaging the microchip, it is recommended to clean the chip with a new paper towel.

It is also possible to take a closer look at the battery connector terminals to determine if they're damaged or cracked. If this is the case, carefully attaching them back can usually restore the function of the key fob. In the same way, you can examine the buttons to see if they are worn or damaged. If the buttons are loose, they can be soldered back regardless of whether the button is actually snapped off.

Interference Signals

Few things are more frustrating than staring at an "No Fob Detected" message when you attempt to start your car. It can happen at the most unfavorable possible times, like when you're running late to work or have to pick up your children from school/daycare. The good news is that there are a few steps you can follow to resolve the issue and determine the cause.

Interference signals can interfere with the remote key fob's signal from the vehicle, causing it to not function properly. This could be caused by things like weather conditions, buildings, and transmitters that use the same frequency. Interference can also occur when you have an aftermarket device installed in your vehicle that transmits at the same frequency as the key fob.

In addition, if the key fob is exposed to water or salt seawater, it may be damaged. Water can penetrate the rubber seals of the electronic chip particularly when the key fob has been submerged in water for a prolonged time. The chip may cease to function and may require replacement of the keyfob. 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 work the chip, it is likely to be fried and will require to be replaced.

Locking/unlocking the Doors

The buttons on the keys send electronic signals to a solenoid within the car, which converts that signal into a mechanical action that locks and unlocks the doors. If your door lock fails to work it could be because of an issue with the solenoid. This will require experts from repair shops to analyze.

A dead 12 volt can cause the fob to stop working effectively. This can happen if the battery loses its charge or the contacts become corroded and stop conducting electricity. This issue can be resolved in minutes with a new battery.

If the key fob doesn't work after you change the battery or program it again the issue could be with the receiver module. This device interprets radio frequency signals sent by the key fob to control the vehicle. If it breaks down it could be costly to fix.

To determine if this is the case, start by inserting your spare keys into the key slot and turning the ignition to ON. Press the key fob two times in a period of 10 seconds, without removing it. The Mazda 3 system will now synchronize the key with the car and allow you to use it as your primary remote for driving. You can program up to three keys in this manner.