It happens to every car owner eventually: you press the button on your key fob, and nothing. Or maybe you have to press it multiple times to get your car to respond. These are classic signs that your car key fob battery is dying and needs replacing. While you might immediately think of a mechanic or dealership, replacing a car key fob battery is often a simple DIY task. The key to a smooth and successful replacement? Knowing the correct Car Key Fob Battery Size.
This guide, brought to you by the automotive experts at keyfobprog.com, will walk you through everything you need to know about car key fob batteries, with a special focus on finding the right size for your vehicle. We’ll cover identifying the battery size, the common types you’ll encounter, and step-by-step instructions to replace it yourself, saving you time and money.
Identifying Your Car Key Fob Battery Size
Before you even think about taking apart your key fob, the first step is to determine the correct car key fob battery size. Luckily, there are a few ways to find this information, often without even needing to open the fob itself.
Check Your Key Fob Case
Many car key fobs are designed with battery information readily available. Examine your key fob closely. Look for embossed letters and numbers on the back of the fob or inside the key sleeve, if your fob has one. Manufacturers often imprint the battery type directly onto the case.
These markings usually correspond to a standardized battery size. Common markings you might find include CR2032, CR2025, CR2016, CR1632, or CR1620. These codes indicate the battery type and dimensions, ensuring you purchase the correct replacement.
Consult Your Owner’s Manual
Another reliable source of information is your vehicle’s owner’s manual. Check the index or the section on vehicle maintenance. Manufacturers often include specifications for various components, including the car key fob battery size. While it might take a moment to locate, the owner’s manual is a definitive guide for your specific car model.
When in Doubt, Open the Key Fob
If you can’t find the battery size externally or in your manual, don’t worry. Opening your key fob is usually straightforward. You’ll need a few simple tools:
- A thin, flat blade: A watch knife or small flathead screwdriver works well for prying open the case.
- A precision screwdriver: Between 1.4mm and 2.4mm, depending on your fob’s screws (if any).
- Tweezers: Helpful for handling the small battery.
Steps to Open Your Key Fob and Identify the Battery:
- Locate the opening point: Most key fobs have a small notch or seam indicating where to pry them open.
- Gently pry the case: Insert your thin blade into the notch and gently twist or pry to start separating the two halves of the fob. Work your way around the seam, carefully releasing the clips or fasteners holding the case together. Avoid forcing it open, as this could damage the fob.
- Take a picture: Before removing the battery, take a photo of the internal components, especially the battery orientation. This will be invaluable when you reassemble the fob.
- Identify the battery size: Once open, you’ll see the battery. The car key fob battery size is usually printed directly on the battery itself. Note down this code (e.g., CR2032).
Common Car Key Fob Battery Sizes
While there’s some variation depending on the car manufacturer, model, and year, several battery sizes are commonly used in car key fobs. Understanding these common sizes will help you quickly find the right replacement.
- CR2032: This is by far the most common car key fob battery size. It’s a 3V lithium coin cell battery, known for its long life and reliability. Many brands, including Honda, Toyota, Nissan, and Hyundai, frequently use CR2032 batteries.
- CR2025: Slightly thinner than the CR2032, the CR2025 is another 3V lithium coin cell. It’s sometimes used in slimmer key fobs. While it can often substitute for a CR2032 in a pinch, it may have a slightly shorter lifespan due to its lower capacity.
- CR2016: Even thinner than the CR2025, the CR2016 is a 3V lithium coin cell used in very slim key fobs. It’s less common than CR2032 and CR2025 but still found in some models.
- CR1632 & CR1620: These are smaller diameter 3V lithium coin cells. Less frequently used than the CR20xx series, they are still found in certain car key fobs.
- CR1220: A smaller 3V lithium coin cell, the CR1220, like the CR16xx series, is less common but used in some specific car models, such as certain Honda vehicles which may use a CR1250 as mentioned in the original article, potentially a typo for CR1220 or a less common variant.
It’s crucial to always verify the specific battery size for your key fob rather than assuming it uses a common size. As the original article mentions, even within the same car make and model, battery requirements can vary. For example, while many Ford key fobs might use a CR2032, a Ford Mustang key fob could require two batteries, and potentially a different size altogether.
Step-by-Step Guide to Replacing Your Car Key Fob Battery
Once you’ve identified the correct car key fob battery size, replacing it is a simple process. Here’s a step-by-step guide:
- Gather your tools and new battery: You’ll need the tools mentioned earlier (thin blade, precision screwdriver, tweezers) and the correct replacement battery. Purchase a high-quality lithium coin cell battery of the identified size for optimal performance and longevity.
- Open the key fob: Follow the steps outlined earlier to carefully open your key fob case.
- Remove the old battery: Use tweezers or your fingertip to gently remove the old battery. Note the orientation of the battery (positive side up or down) before removing it if you didn’t take a picture earlier.
- Insert the new battery: Place the new battery into the battery compartment, ensuring it’s in the correct orientation (match the positive and negative markings or refer to your photo).
- Close the key fob: Carefully snap the two halves of the key fob case back together. Ensure it’s securely closed and all fasteners are engaged.
- Test your key fob: Try using your key fob to lock and unlock your car and start the engine (if applicable for your fob type). If it works, you’ve successfully replaced the battery!
Importance of Using the Correct Car Key Fob Battery Size
Using the correct car key fob battery size is essential for several reasons:
- Proper Functionality: The wrong size battery may not make proper contact with the terminals inside the key fob, leading to intermittent or no function.
- Battery Life: Using a battery with incorrect specifications can affect its lifespan and the overall performance of your key fob.
- Damage Prevention: Forcing a battery that’s too large into the compartment could damage the key fob’s internal components.
- Secure Fit: The correct size ensures a snug and secure fit within the battery compartment, preventing movement and maintaining consistent power supply.
Conclusion
Replacing your car key fob battery is a straightforward DIY task that can save you a trip to the dealership and unnecessary expenses. The most crucial step is identifying the correct car key fob battery size for your vehicle. By following the methods outlined in this guide – checking the fob case, consulting your owner’s manual, or carefully opening the fob – you can confidently determine the right battery and restore your key fob to perfect working order. Remember to always double-check the size and use a quality replacement battery to ensure reliable performance for years to come.
