How to Replace a Key Fob Battery | O'Reilly Auto Parts

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Replacing a key fob battery is a straightforward DIY task, and requires only a basic screwdriver or other prying tool in most cases. This video demonstrates how to replace most key fob batteries, but be sure to know the specifications for the key fob for your vehicle before getting started. Restore your vehicle’s security and accessibility with a new key fob battery and the right advice from the parts professionals at O’Reilly Auto Parts.

Tools & Materials List

Step-by-Step Instructions

Additional Resources

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The key fob for your vehicle is responsible for controlling the alarm system, keyless entry and power locks, and in some cases, may also be used for remote starting. Key fobs feature disc or watch batteries that can lose power over time and with use. When key fob batteries become weak or die, it may limit the range at which you can use the fob, or prevent you from locking or unlocking your doors, remote starting your vehicle, or using the panic button when necessary.

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In three images, our expert locates the key fob's separating seam, pries it open, and separates the fob into two parts.

Step 1: Pry Open the Key Fob

Start by locating the small notch on the seam between the two halves of the fob. Use a small flathead screwdriver, a coin, or a knife to gently pry at the notch, working your way around the seam carefully until the two halves come apart.

Do It Right: Be careful to keep your fingers out of the way of your tool to prevent injury.

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The separated key fob is shown with the old battery in view.

Step 2: Locate the Key Fob Battery

Once the fob is open, locate the battery. Take note of the battery's orientation as you remove it so that your new battery can be installed properly.

Do It Right: Key fob and watch batteries, also called disc batteries, are labeled positive and negative on each side if you need to determine which way the current battery is facing.

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In three images, the new key fob battery is shown facing up and installed into the key fob.

Step 3: Install New Key Fob Battery

Install your new battery, ensuring it is facing the same way as the one you removed.

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In two images, the key fob is snapped back together and tested to see if the battery works.

Snap the two halves of the fob back together. Try it to make sure it's working.

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When it’s time to change a weak or dead battery in your car’s key fob, following these step-by-step instructions and referencing your vehicle’s owners manual can help you replace your fob battery in no time. Make sure to check what type of battery you need for your key fob before beginning this repair. If you’re not sure what battery is right for your key fob, or if you need help finding the right coin battery, our Parts Professionals can help you with all the supplies you need to get the job done right.

The automotive repair work depicted in this series is performed under the direction of the manufacturer of the product featured. Prior to undertaking any of the demonstrated repairs on your vehicle, we suggest you consult with a certified mechanic or another professional who can adequately advise you of the proper repair or remedy required. O’Reilly Automotive Stores, Inc. and its affiliates (“O’Reilly”) disclaims any responsibility for injury or damage resulting from a viewer’s attempt to recreate the repairs shown in this series.

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