How to Change the Battery in a Key Fob: A Step-by-Step Guide for Every Vehicle

In today’s high-tech vehicles, it’s imperative to have a key fob that works. That’s why every driver should know how to change the battery in a key fob or know a good locksmith. The good news is that it’s a simple thing to learn. Plus, once you learn it, you’ll be able to leverage all the benefits of a working fob, like using remote starting, unlocking and locking the doors, and more.

When a car key fob battery is low, you can’t do any of those things. So, battery replacement skills are good to have. Most people contact a locksmith for key fob reprogramming because locksmiths know how to fix a key fob. Signs that the battery is low include delayed responses, being unable to lock or unlock doors, and needing to press buttons multiple times for common functions. Knowing how to change the battery in a key fob can prevent many problems for car owners.

Why Changing the Key Fob Battery is Important

Even if you know how to change the battery in a key fob, it helps to know when and why to do it. Key fob battery replacement opens the door, no pun intended, to lots of useful functions, like opening the trunk, remote engine starting, unlocking and locking all vehicle doors, and sometimes more advanced features.

However, before you learn how to replace a key fob battery, find out how to open a key fob and how to identify the key fob battery type. Remember that a non-functional fob might mean you end up locked out of your own vehicle, unable to start it, or unable to lock the doors or open the trunk. That’s a potential safety risk, so it should be avoided. But how?

Begin by keeping your fob in excellent condition and changing the battery at regular intervals. Well, what if the key fob is not working after a battery change? That is a good time to visit a locksmith. While replacement is relatively easy to do on your own, if you don’t want to do it or don’t know how to change the battery in a key fob, a professional locksmith is the alternative. The great thing about locksmiths is that they can quickly put the right battery in, repair the fob if it’s broken, or even reprogram it if that is required.

How to Identify the Right Battery for Your Key Fob

Here are some useful tips for knowing how to identify the right key fob battery type after you learn the basics of how to replace the key fob battery:

• The CR2032 key fob battery is the most common across most makes and models of vehicles.
• Most key fob battery replacement units, like the CR2032, are coin-shaped lithium batteries with excellent reliability and shelf life.
• You MUST use the correct battery type, or you risk a non-functional or damaged fob.
• The battery’s type is printed on the flat surface.
• Vehicle owner’s manuals contain information about the type of battery to use.
• Purchase reputable brands instead of discount, “no-name” brands when buying batteries.
• Best places to find fob batteries are electronic stores, automotive retailers, and online sellers.
• Check expiration dates when buying, and make sure all packaging is intact and not tampered with.
• Shop around. Prices vary a lot between sellers, so a few minutes of research can save you some money.

Step-by-Step Guide to Replacing a Key Fob Battery

Step 1: Open the Key Fob

First, find the seam of the unit. It’s usually along the thinnest part, or side, of the device. Use a special tool or any small, non-metallic object to pry open the seam. If there are screws, remove them first. Be careful not to touch or damage the inner components of the fob when pulling it apart. Never force it open, or you’ll risk breaking the unit and rendering it useless.

Step 2: Remove the Old Battery

After the fob is completely opened, find the location of the battery. It’s usually very obvious, but you might need to carefully slide it out or unclip it from its seating in order to remove it. Take a picture of the battery’s position before removing it. Duplicate that orientation, for positive and negative poles, when putting the new battery in. Metal tools can permanently damage the fob by short-circuiting it, so use plastic ones or your fingernail to remove and replace the battery.

Step 3: Insert the New Battery

Hold the new battery in between your fingers and gently insert it into the slot in the same position as the old battery. Pay close attention to the positive and negative sides as you do this. Most fobs have marks that show the “+” and “-” signs. Insert the new battery until it is snug and fully seated. If it doesn’t slide in easily, check to see that you have the negative and positive poles in the right orientation and that you’re using the right battery size.

Step 4: Reassemble the Key Fob

Place the two halves of the unit in proper alignment and snap them back together. If there are screws, snap the two halves together first, and then put the screws in. Firmly press the two halves until you hear a snap, which indicates that all is well. It’s essential that all the component parts are correctly lined up, inserted, and positioned. Otherwise, even a new battery won’t be of any use. Fobs tend to be user-friendly, and most people don’t have any difficulty with this step.

Step 5: Test Your Key Fob

Almost done. After the new battery is in place and the unit is fully reassembled, get ready to perform a few tests by standing a few yards away from your vehicle. Attempt to use the fob to lock and unlock doors, open the trunk, start the vehicle, or whatever functions your unit is capable of. If all goes well, then you have successfully installed the new fob battery. If something doesn’t work right, check all the connections by disassembling the fob once more. Then reassemble it and perform the tests again.

Troubleshooting Common Issues After Battery Replacement

What to do if the key fob still doesn’t work

Always check the car’s official owner’s manual first, and then consult a few online resources to see if you can quickly diagnose and remedy the problem. Be sure that the battery is properly “seated” in the fob and that the unit has been snapped or screwed together correctly. If there’s still a problem, it’s likely that the unit needs to be reprogrammed, which is a task that your local locksmith can perform.

Possible reprogramming needs and how to perform them

The vehicle owner’s manual will sometimes include instructions about how to reprogram a fob after the battery has been changed. This is particularly true of newer models. Usually, it’s necessary to turn the ignition on and then off and press a specific sequence of buttons on the fob to reset it.

When to seek professional help

If you’ve done all of the above steps and your fob still doesn’t work, there’s probably something more complex going on than a dead fob battery. Contact a reputable locksmith who can diagnose the problem. If the locksmith discovers a major issue with the vehicle, they’ll direct you to contact a dealer or a licensed mechanic. Fortunately, your locksmith can usually deal with the problem by reprogramming the fob, saving you a potentially costly trip to a mechanic.

Tips to Extend the Life of Your Key Fob Battery

• Strive to keep the key fob away from temperature and humidity extremes.
• Store fobs in safe, dry, controlled locations, like protective cases inside your home. Avoid storing them in the glove compartment unless the vehicle is garaged when not in use.
• Fob batteries can easily deplete themselves, even when they aren’t used. That’s because electronic devices have the potential to disrupt the fob’s electrical system. So, keep fobs away from phones, wireless chargers, tablets, and microwave ovens.
• Fobs are delicate, so avoid dropping them onto hard surfaces. Use a cushioned carrying case if possible.
• Don’t press too hard on the unit’s buttons. Only press down enough to make an electrical contact between the button and the inner workings of the device. Pressing too hard can shorten the life of the fob.

Key Takeaways

While it might seem pretty technical at first, changing a key fob battery is actually a very simple and inexpensive job that almost anyone can do. Making sure your vehicle key fob is in good working order is a core part of everyday convenience and security. It’s always helpful to check for signs that your car key fob battery is low or completely out of power.

Follow the easy steps outlined above to do a quick and painless battery replacement. Likewise, know how to reset the key fob after a battery change and where to go for help with key fob reprogramming. Reputable locksmiths know how to fix a key fob on any make or model of vehicle. Keep your car fully accessible and secure by monitoring the health of the key fob battery and knowing the phone number of a good locksmith.