Changing the Battery in Your Mazda 3 Key Fob

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

A spare key fob for your Mazda 3 is an inexpensive method to avoid having to be towed by a dealership to let them re-program your keys.

Battery Replacement

You can change the battery on your Mazda 3 keyfob at home. It is recommended to replace it when the battery is dead or you see a message reading "Low keyfob battery" on the multi-information display. Replace battery."

You'll need to use an flathead screwdriver along with tape and patience to open the case. Insert the head of the flathead screwdriver into a notch, or gap on the bottom metal of the mazda 2 key replacement 3 key fob to pry the lower half off. Repeat this step for the top metal part, but be careful not to damage the rubber ring on the bottom of the key fob's case.

There is a slot on the opposite side of the case that contains the battery. Use the flathead screwdriver with tape to gently the case open, beginning at one end and moving to the other. Take out the old CR2025 and replace it with a new one, making sure to put it on its face to ensure proper the polarity. Finally, place the battery cap back on and reattach both sides to the key fob's case, pressing until you can hear them click.

Now that you've replaced the battery, test the fob to make sure it functions by locking and unlocking your doors. If everything seems to be in good order the Mazda 3 remote features can be used again.

Pairing Issues

This could indicate that the transmitter in your car has been damaged. This usually requires an expert repair and will likely require a new replacement key fob.

If you've tried replacing the battery and reprogramme the key fob but it hasn't worked the chip inside the key fob could be faulty. This could happen if the key fob has been dropped on hard surfaces, exposed to salt water, or even touched by dirty hands.

You'll need the small "key", which is inserted into the seam to remove the circuit board to identify the problem. Then, you will be able to check for any corrosion or damage on the electronic chip. To prevent damaging the microchip, it is recommended to use a clean paper towel.

It is also possible to take a close look at the battery connector terminals to examine if they're cracked or broken. If this is the case, then carefully reconnecting them can usually restore the function of the key fob. It is also possible to check the buttons for damage or wear. If the buttons are loose, they can easily be soldered back in place and also if 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 seeing the message "No Fob Detected". This typically happens at most unpopular time, such as when you're running late for work or if you're picking up kids from daycare/school. The good thing is that there are a few steps you can take to investigate the issue and determine what is causing it.

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

Additionally, if the key fob is exposed to salt or the water, it might be damaged. The rubber seals on the electronic chip may be penetrated by water, especially if it is submerged for long periods of time like in a swimming pool or at the beach. This could cause the chip to stop functioning and require replacement of the key fob. If you have a programmable key you can clean the chip with isopropyl Alcohol or an electronic cleaner to help it return to functionality. If this doesn't work, it is likely that the chip has fried and requires replacement.

Locking and unlocking of the Doors

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

A low-voltage battery can cause the fob to stop functioning properly. This could happen if your battery is not charged or if the contacts are damaged. The good news is that a new battery can solve this issue in only minutes.

If the key fob doesn't work after you have changed the battery or program it again then the problem may be related to the receiver module. This device receives radio frequency signals from the key fob and interprets them to control the vehicle's functions. It can be a costly repair if it becomes faulty.

To determine if this is true, insert your spare key in the key slot. Then, turn the ignition ON. Press the key fob two times within 10 seconds, but without taking it out. The Mazda 3 system will now be able to synchronize the key with your vehicle and you can then use it as your primary remote for driving. You can program up to three keys in this way.