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How to Replace a Key Fob Battery

key fob

Key fobs make it easier to get into vehicles. Opening the doors and the trunk or tailgate are easier than ever with this device. Some are separate from the key and others have the key built right in. Others are called “smart keys” where you don’t even have to take the fob out of your pocket to open the doors, trunk, or even start the car. The battery is only there for the fob to control remote functions. The battery being weak or dead does not prevent you from starting your vehicle, only from using the fob itself. Replacing the battery is easy and they can be found at any auto part store, supermarket, or pharmacy.

Part 1 of 1: Replacing the battery

Materials needed

opening key fob with a screwdriver

Step 1: Open your key fob. Generally, all you need to open up your key fob is a strong fingernail. If that doesn’t work, use a small flat head screwdriver to gently pry it open.

To avoid breaking the key fob shell, pry gently from more than one location around the fob.

  • Note: Some all-in-one key fob/key combinations require you to split the remote from the key first as pictured below. Battery replacement procedure is the same.

all in one key fob with battery shown

Step 2: Identify your battery. Now that you have the fob opened, if you have not already purchased the replacement battery, you can now see the battery type/number printed on the battery and purchase one.

Note the battery + and - position as some fobs may not have the labeling inside.

key fob battery and location

Step 3: Replace the battery. Insert the battery in the proper position.

Gently snap the fob shell back together, making sure it snaps together completely.

Try all the remote buttons to verify it is working.

By noticing the signs that your key fob is giving you, it will be easy to replace the battery and restore its functionality. Make sure that a high-quality replacement battery is replaced correctly or just have an experienced mechanic, like one from YourMechanic, inspect and replace the key fob battery for you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

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