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. Luckily, this is an easy fix with a simple battery replacement from an hardware store or a big box retailer.

Adding a spare key fob to your Mazda 3 can be an inexpensive way to save yourself from the hassle of being transported to a dealership and having them reprogram your keys.

Battery Replacement

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

You'll need to use a flathead screwdriver, tape and patience to open the case. Put the head of the flathead screwdriver into a notch, or gap on the bottom metal of the Mazda 3 key fob to cut off the lower half. Repeat the procedure for the top piece of metal but be careful not to damage the rubber ring that is on the bottom of the case.

Once the fob case has been opened, you'll notice the slot on either side of the case that houses the battery. Make use of the tape-wrapped flathead screwdriver to gently open the case, starting on one side and then shifting to the other. Take out the old CR2025 and replace it with a brand new one, ensuring that you place it face-up to ensure proper orientation. Put the cap of the battery on again, and then attach both sides of your key fob case by pressing until they click.

Now that you've replaced the battery, test the fob to ensure it's working by locking and unlocking your doors. If everything looks good the Mazda 3 remote features can be used again.

Pairing Issues

If your key fob has stopped working suddenly it could be a sign that the transmitter inside your car is damaged. This usually requires an expert repair and may need a new key fob.

If you have tried replacing the battery and reprogramming the key fob, but how much does it cost to replace a mazda key not solve the issue it could be that the chip in the key fob might be damaged. This can happen if the key fob has been dropped on hard surfaces and exposed to salt water or even brushed by dirty hands.

To determine the cause, you will need to locate a small "key" that is embedded into the edge of the fob which allows you to open it and take out the circuit board. Then, you can check the chip for corrosion or damage. To avoid damaging the chip, it's best to use a fresh paper towel.

You can also take a close look at the battery connector's terminals to check if they're cracked or broken. If this is the case, then carefully connecting them back can often 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 a button has physically snapped off.

Interference Signals

There is nothing more frustrating than staring at the "No Fob Detected" message when you attempt to start your car key remote replacement. It typically happens at most awkward time, such as when you're late for work or picking up children from daycare or school. There are some things you can do to find out what's causing the problem.

Interference signals can cause the remote key fob to stop working properly. This could be caused by objects such as buildings, weather conditions and transmitters that operate on the same frequency. Interference can occur when your vehicle has aftermarket equipment that transmits at the same frequency as your key fob.

Additionally, if the key fob is exposed to salt or the water, [Redirect-302] it might be damaged. The water can penetrate the rubber seals of the electronic chip especially when the key fob is submerged in water for an extended duration. The chip may stop working and require replacement of the keyfob. If you have a programmable key, you can clean the chip with isopropyl Alcohol or an electronic cleaner to aid in its come back to normal. If this doesn't help then it's likely that the chip is fried and requires replacement.

Locking and unlocking of the Doors

The key fob's buttons 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 does not work it could be due to an issue with the solenoid. This requires expert repair shops to analyze.

A low-voltage battery can also prevent the fob from functioning properly. This can happen when your battery loses its charge or if the contacts become damaged. The good news is that a new battery is able to solve this issue in only minutes.

The receiver module may be the reason why the key fob won't work after replacing 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 fails, it can be expensive to fix.

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