It’s a familiar scenario for many car owners: you press the unlock button on your key fob, and nothing happens. Or perhaps you need to press it multiple times before your car finally responds. This is often the first sign that your key fob battery is dying and needs replacing. While you might immediately think of a costly trip to the dealership, replacing your key fob battery is often a simple DIY task. But before you start, the most crucial question is: What Size Battery For Key Fob do you actually need?
This guide from the experts at keyfobx.com will walk you through everything you need to know about key fob batteries, focusing on identifying the correct size and replacing it yourself. We’ll cover the common battery sizes, how to find out the right one for your fob, the tools you’ll need, and step-by-step instructions to get your key fob working like new again. No more struggling to unlock your car – let’s get started!
Identifying the Right Key Fob Battery Size
Finding the correct battery size is the first and most important step in replacing your key fob battery. Using the wrong size can prevent your key fob from working and even damage it. Here’s how to determine the battery size you need:
1. Check Your Key Fob Case:
The easiest way to find out what size battery for key fob you need is to check the key fob itself. Many key fobs have the battery size embossed directly on the back of the case or inside the battery compartment. Look closely for a combination of letters and numbers.
Common markings include:
- CR2032: This is the most common key fob battery size. It’s a 20mm diameter, 3.2mm thick coin cell lithium battery.
- CR2025: Similar to CR2032 but slightly thinner (2.5mm thick). It can sometimes be used as a substitute for CR2032 in a pinch, but it’s best to use the specified size.
- CR2016: Thinner still (1.6mm thick), less common in key fobs but still used in some models.
- CR1632: 16mm diameter and 3.2mm thick, another less common size.
- CR1620: 16mm diameter and 2.0mm thick.
2. Consult Your Car Owner’s Manual:
If you can’t find the battery size on the key fob itself, your car owner’s manual is another excellent resource. Look in the index for “key fob battery,” “remote battery,” or “keyless entry battery.” The manual should specify the correct battery type and size for your vehicle’s key fob.
3. Online Resources and Battery Finders:
Several online resources can help you determine what size battery for key fob you require. Websites like battery finders (often found on battery retailer websites) allow you to input your car’s year, make, and model to find the compatible key fob battery. You can also search online forums or communities specific to your car model; other owners may have already shared information about their key fob battery replacements.
4. Open the Key Fob (Carefully):
As a last resort, if you can’t find the battery size information elsewhere, you can carefully open your key fob to identify the battery already inside. Here’s how to do it safely:
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Gather your tools: You’ll need a thin, flat tool like a watch knife or small flathead screwdriver. Precision screwdrivers (1.4mm to 2.4mm) might also be necessary for screws in some fobs.
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Locate the opening point: Most key fobs have a small notch or seam that indicates where to pry them open.
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Gently pry the case: Insert your tool into the notch and gently twist or pry to separate the two halves of the fob case. Work your way around the seam, applying gentle pressure. Avoid forcing it open, as you could damage the case.
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Take a picture: Before removing the old battery, take a photo of the inside of the key fob, noting the battery’s orientation (+ and – sides). This will be helpful when you install the new battery.
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Identify the battery size: Once open, you’ll see the battery. The size should be printed directly on the battery itself.
Important Note: While most key fobs use a single coin cell battery, some, like certain Ford Mustang key fobs, may use two batteries. Always check your specific key fob to confirm.
Tools You’ll Need for Key Fob Battery Replacement
Once you know what size battery for key fob to buy, gather these simple tools for the replacement process:
- New Battery: Purchase the correct size lithium coin cell battery (e.g., CR2032, CR2025, etc.). You can find these at most drugstores, supermarkets, and electronics stores, as well as Interstate All Battery Centers.
- Thin Blade or Small Screwdriver: For prying open the key fob case. A watch knife, small flathead screwdriver, or even a guitar pick can work.
- Precision Screwdriver Set (Optional): Some key fobs are held together with tiny screws. A precision screwdriver set with sizes ranging from 1.4mm to 2.4mm might be needed.
- Tweezers (Optional): Tweezers can be helpful for removing and installing the small battery, especially in tight spaces.
- Phone Camera: Essential for taking a reference photo of the key fob interior before removing the old battery.
Step-by-Step Guide to Replacing Your Key Fob Battery
Now that you have the correct battery and tools, follow these steps to replace your key fob battery:
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Open the Key Fob: Using your chosen tool, carefully pry open the key fob case as described earlier. Work gently and avoid excessive force.
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Take a Reference Photo: Before removing the old battery, take a clear photo of the inside of the key fob, paying attention to the battery’s orientation (+ and – sides) and the placement of any other components.
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Remove the Old Battery: Use your fingers or tweezers to gently remove the old battery. Some fobs have small clips or fasteners holding the battery in place; carefully move these aside as needed.
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Install the New Battery: Insert the new battery, ensuring it’s oriented correctly according to your reference photo (+ side up or down as needed). Make sure it’s securely seated in the battery compartment.
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Close the Key Fob Case: Carefully snap the two halves of the key fob case back together. Ensure they are firmly closed and all fasteners are engaged. If your fob has screws, tighten them gently but securely.
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Test Your Key Fob: Test the buttons on your key fob to ensure it’s working correctly. Unlock and lock your car, and test any other functions like the trunk release or panic button.
Tips for a Smooth Key Fob Battery Replacement
- Work in a clean, well-lit area: This will help you see the small parts clearly and avoid losing anything.
- Be gentle: Key fobs are delicate. Avoid using excessive force when opening or closing the case or handling internal components.
- Don’t touch the circuit board: Avoid touching the circuit board or any wiring inside the key fob to prevent damage.
- Dispose of old batteries properly: Lithium coin cell batteries should be recycled properly. Check your local regulations for battery disposal.
Where to Get Key Fob Battery Replacements and More
Knowing what size battery for key fob is just the start. You can purchase replacement batteries at many locations, including:
- Interstate All Battery Centers: For a wide selection of key fob batteries and expert advice.
- Drugstores and Supermarkets: Common coin cell batteries like CR2032 are widely available.
- Electronics Stores: Retailers specializing in electronics will also carry a range of batteries.
- Online Retailers: Amazon and other online retailers offer convenient purchasing options.
And remember, if you ever need a spare key fob or find yourself needing a replacement, Interstate All Battery Center locations offer key fob replacement services, providing a convenient and cost-effective alternative to dealership prices.
Replacing your key fob battery is a simple and cost-effective way to keep your car working smoothly. By following these steps and knowing what size battery for key fob you need, you can avoid dealership visits and get back on the road with a fully functional key fob.
