Changing the Battery in Your Mazda 3 Key Fob

There's nothing more frustrating than returning to your vehicle after a long day, and discovering that the key fob battery is dead. Fortunately, this is an easy fix with an easy battery replacement at the hardware store or big box retailer.

A spare key fob for your mazda key fobs 3 is an inexpensive way to avoid having to take it to a dealership in order to have them re-program your keys.

Battery Replacement

You can change the battery on your Mazda 3 keyfob at home. However, you should replace the battery if it goes out of service, or if the key fob displays a message in the multi-information display saying, "Low key fob battery. Replace battery."

To open the key fob's case You'll need a tape wrapped flathead screwdriver and some patience. Put the flathead screwdriver's tip in a notch, or gap in the bottom part of the mazda 3 spare key 3 key fob to pry the lower half off. Repeat the process for the top metal part but be careful not to scratch the rubber ring at bottom of the key fob's case.

There's a slot on each side of the case, where you can find the battery. Use the tape-wrapped flathead screwdriver to gently pry the case open, starting on one side before moving to the next. Remove the battery that was used and place in a new CR2025 and make sure it's facing up to ensure the correct polarity. Install the cap on the battery the other side and attach both sides of your key fob case by pressing until they click.

After replacing the battery check the fob to confirm it is working by locking and unlocking your doors. If everything seems to be in good order then your Mazda 3 remote features can be used again.

Pairing Issues

If your key fob stopped suddenly it could mean that the transmitter in the car is damaged. This is usually a matter for a professional and you will require a brand new key fob.

If you've attempted to replace the battery and reprogramme the key fob, but it's not working then the chip in the key fob could be defective. This could happen if the keyfob was dropped or exposed to saltwater or handled by dirty fingers.

To determine the cause of the issue it is necessary to find a small "key" that is embedded into the edge of the fob which allows you to open it up and remove the circuit board. Then, you can examine the chip for damage or corrosion. It is best to clean the paper towel to keep the microchip from being damaged.

You can also examine the battery connector terminals to determine if they're cracked or broken. If this is the case, then carefully reconnecting them will usually restore the function of the key fob. You can also check the buttons for damage or wear. If the buttons are loose, they can be soldered back into place as well unless the button is actually snapped off.

Interference Signals

Few things are more annoying than looking at a "No Fob Detected" message when trying to start your car. This can happen at the most inconvenient occasions, such as when you're late to work or pick up your children from daycare or school. There are some things you can try to figure out the root of the issue.

Interference signals can cause the remote key fob not to function in a proper manner. This can be caused from objects such as weather conditions, buildings as well as transmitters operating on the same frequency. Interference may also occur if you have aftermarket equipment installed in your vehicle that transmits at the same frequency as the key fob.

Additionally, if the key fob is exposed to water or salt the water, it might be damaged. The rubber seals on the electronic chip can be shattered by water, especially when it is submerged over long periods of time like in the ocean or a pool at the beach. This could cause the chip to stop functioning and require replacement of the key fob. If you have a programmeable key, you can clean the chip with isopropyl Alcohol or an electronic cleaner to aid in its come back to normal. If this does nothing then it's likely that the chip has burned out and needs to be replaced.

Locking/unlocking the Doors

The buttons on the key fob send electronic signals to the solenoid of the car, which then transforms the signal into mechanical action. This locks and unlocks doors. If the door lock is not working, the problem could be a solenoid issue that requires investigation with the help of an expert repair shop for autos.

A dead battery of 12 volts can cause the fob to stop functioning properly. This can happen if the battery is unable to charge or if the contactors get corroded and stop transferring electricity. This problem can be fixed within a few minutes using a new battery.

The receiver module may be the cause of the issue if the key fob doesn't work after you replace the battery or re-program the device. This device receives radio frequency signals from the key fob and interprets them to control the vehicle's functions. If it malfunctions it could cost a lot to repair.

To verify if this is true, insert your spare key in the key slot. Then turn the ignition on. Press the key fob two times in a period of 10 seconds, without removing it. The Mazda 3 system synchronizes the key with the vehicle, so you can use it as your primary remote for driving. You can program up to three keys this manner.