Is your car key fob starting to feel a little… unresponsive? Do you have to press the unlock button multiple times before your car deigns to acknowledge your presence? It might not be your car being temperamental; the battery in your key fob is likely running out of juice.
Like any battery, key fob batteries wear down over time. While you could head to a dealership or auto repair shop and pay for a professional replacement, you can easily tackle this task yourself. Replacing a key fob battery is a straightforward DIY job that can save you both time and money. Plus, it’s empowering to know you can handle this common car maintenance task on your own.
So, How Do You Put A Battery In A Key Fob? It’s simpler than you might think. With just a few common tools and a little patience, you can breathe new life into your car remote. Let’s get started.
Identifying Your Key Fob Battery Type
Before you even think about opening your key fob, the first crucial step is to figure out what kind of battery you need. You don’t want to disassemble everything only to realize you have the wrong replacement battery on hand.
Often, your key fob case itself will give you a clue. Take a close look at the back of your fob or even inside the key sleeve. You might find embossed letters and numbers indicating the battery type.
While many car key fobs use a standard CR2032 coin cell battery – a common type of watch battery – it’s not a universal rule. Battery types can vary depending on your car’s year, make, and model. For example, some vehicles, like certain Honda CR-V models, might require a CR1250 battery. Even within the same car model, variations can exist; a Ford Mustang key fob, for instance, can sometimes take two batteries.
If you can’t find the battery type indicated on your key fob, don’t worry. The next step, carefully opening the case, will reveal the battery you need.
Tools You’ll Need to Replace Your Key Fob Battery
Fortunately, you probably already have most of the tools required for this simple repair around your house. Gather these items before you begin:
- A Thin Blade or Pry Tool: A watch knife, a small flathead screwdriver, or even a guitar pick can work. This is for gently prying open the key fob case. Avoid using anything too sharp that could damage the plastic.
- Replacement Battery: Once you know the type (either from the fob itself or after opening it), purchase the correct battery. CR2032 batteries are widely available at drugstores, supermarkets, and online retailers.
- Precision Screwdriver (Potentially): Some key fobs use tiny screws to secure the case. A precision screwdriver set, typically used for electronics repair, may be necessary. Sizes between 1.4mm and 2.4mm are common, but it depends on your specific fob.
- Tweezers: These are helpful for grabbing and maneuvering the small battery, especially in tight spaces within the key fob.
- Smartphone Camera: This is an invaluable tool! You’ll use it to take photos as you disassemble the fob, ensuring you can put everything back together correctly.
Step-by-Step Guide: Replacing Your Key Fob Battery
Now that you’ve gathered your tools and identified (or are about to identify) your battery type, let’s walk through the process of replacing your key fob battery step-by-step.
Step 1: Carefully Open the Key Fob Case
This is often the trickiest part, but patience is key. Locate the seam where the two halves of the key fob case meet. Many fobs have a small notch or indentation to give you a starting point.
Using your thin blade or pry tool, gently insert it into the seam at the notch or any point where you can get a slight opening. Do not force it. Work your tool around the perimeter of the case, gently prying as you go. Imagine you are carefully peeling an orange – you want to separate the halves without cracking or breaking anything.
Some key fobs are held together with tiny screws. If you encounter resistance or can see screws, you’ll need to use your precision screwdriver to remove them before prying the case open.
Step 2: Remove the Old Battery and Note the Polarity
Once the case is open, take a moment to take a picture with your phone. Capture the layout of the inside of the key fob, paying close attention to the battery’s orientation – specifically, which side is facing up (positive or negative). This photo will be crucial for reassembly.
Carefully remove the old battery. In some fobs, the battery is held in place by small clips or a sliding metal piece. Use your tweezers or a fingertip to gently lift the battery out. Note the “+” and “-” markings inside the battery compartment; these indicate the polarity.
Step 3: Insert the New Battery
Take your new battery and install it in the same orientation as the old one. Ensure the polarity matches the markings in the battery compartment (positive side up or down, as noted in your photo). Press the battery firmly into place until it is securely seated.
Step 4: Close the Key Fob Case
Carefully align the two halves of the key fob case and snap them back together. Press firmly around the edges to ensure a secure closure. If your fob had screws, replace and tighten them gently.
Important Tips and Precautions
- Gentle is Key: Never force the key fob case open. Patience and gentle prying are essential to avoid damage.
- Photo Reference is Your Friend: Taking a picture before removing the battery is a simple step that can save you a lot of frustration during reassembly.
- Mind the Polarity: Installing the new battery with the correct polarity is crucial for the key fob to function.
- Avoid the Circuit Board: Be careful not to touch or disturb any of the wiring or the circuit board inside the key fob. Focus solely on replacing the battery.
- Double-Check Battery Type: Before you start, and again before you close the case, ensure you are using the correct replacement battery type.
Conclusion
Replacing your key fob battery is a quick and easy DIY task that can save you a trip to the dealership and unnecessary expenses. By following these simple steps and taking a little care, you can restore your key fob to full working order and avoid the frustration of an unresponsive car remote. So next time your key fob starts acting up, remember you have the power to fix it yourself!
