It's The Ugly Reality About Mazda 6 Key Fob Changing the Battery in Your Mazda 3 Key Fob

It's a pain to get into your car at the conclusion of a long and tiring day and discover that your key fob is dead. Fortunately, it is an easy fix with the simple replacement of a battery at a hardware store or big box retailer.

A spare key fob for your Mazda 3 is an inexpensive option to not have to take your vehicle to a dealer to have them re-program the keys.

Battery Replacement

Change the battery in your Mazda 3 key fob is an easy procedure that you can perform at home. It is recommended to replace it when the battery goes out or 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 and some patience. Find mazda 3 car key or notch in the bottom metal part of the Mazda 3's key fob, and insert the head of the screwdriver into it to pry off the lower part. Repeat the procedure for the top piece of metal but be careful not to scratch the rubber ring at the bottom of the case.

There's a slot on each side of the fob case that contains the battery. Start on the other side of the case and then gently open it. Remove the old CR2025 and replace it with a brand new one, making sure that you put it on its face to ensure the correct polarity. Then, put the cap on the battery and then reattach both sides of the key fob case, pressing until you hear them click.

After replacing the battery, lock and unlock your doors to confirm that the fob is working. If everything looks good then you can begin using the Mazda 3's remote features to drive again!

Pairing Issues

This could be a sign that the transmitter in your car has been damaged. It's usually a task to a professional and you will require a brand new key fob.

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

You'll need an extremely small "key" that is inserted into the seam, in order to remove the circuit board and diagnose the issue. You can then check the electronic chip for damage or corrosion. To prevent damaging the microchip, it is best to use a fresh paper towel.

You may also take a closer look at the battery connector's terminals to check if they're cracked or broken. If this is the case, carefully connecting them back can usually restore the function of the key fob. In the same way, you can examine the buttons to see whether they've been worn out or damaged. If the buttons are loose, they can be soldered back in place in the event that the button has actually snapped off.

Interference Signals

There's nothing more frustrating than trying to start your car only to see the message "No Fob Detected". This typically happens at most awkward time, such as when you're late for work or picking up children from school/daycare. The good news is that there are a few steps you can take to pinpoint the issue and figure out what is causing it.


Interference signals can cause the remote key fob to cease working in a proper manner. This could be due to things like weather conditions, buildings and transmitters using the same frequency. Interference may also occur if you install aftermarket equipment in the vehicle that transmits at the same frequency as the key fob.

The key fob can also be damaged if it is exposed to water or salty water. The rubber seals on the electronic chip may be damaged by water, especially when it is submerged for an extended period of time, such as in a pool or at the beach. This can cause the chip to stop functioning, requiring replacement of the key fob. If you have a programable key you can clean the chip using isopropyl alcohol or an electronic cleaner to aid in its get back to its original functionality. If this does not help, the chip is likely to be damaged and will need to be replaced.

Locking and Unlocking of Doors

The buttons on the fob's key send electronic signals to the solenoid inside the car, which transforms the signal into mechanical action. It locks and unlocks doors. If the door lock isn't working, it could be a solenoid issue that requires some analysis with the help of a professional auto repair shop.

A dead 12 volt can also prevent the fob from functioning properly. This could happen if the battery loses charge or the contacts are corroded and stop transmitting electricity. The good news is that a new battery can fix this issue in just minutes.

The receiver module may be the cause of the issue if the key fob does not function after you replace the battery or re-program the device. The device detects radio frequency signals sent by the key fob to control the vehicle. If it malfunctions it could cost a lot to fix.

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