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. Before you assume there’s a major issue with your vehicle’s remote system, the most likely culprit is a simple one – a dead or dying battery in your key fob. But What Batteries Do Key Fobs Use? This is a common question, and understanding the answer can save you time and potentially money.
The good news is that replacing a key fob battery is usually a straightforward process you can do yourself. You don’t necessarily need to visit a dealership or a mechanic. However, knowing the correct battery type is the first crucial step. While the battery inside your car key remote might seem insignificant, it’s the power source for all the convenience features you rely on daily, from remote locking and unlocking to starting your engine in some newer models.
Common Types of Key Fob Batteries
Most car key fobs rely on small, round batteries known as coin cell batteries. These are lithium batteries known for their long life and consistent power output, perfect for the low-drain, intermittent use of a key fob. While there isn’t a single universal battery for all key fobs, several types are frequently used.
The most common type you’ll encounter is the CR2032 battery. This 20mm diameter, 3.2mm thick battery is a workhorse in the key fob world. Its popularity stems from its balance of size, power, and longevity. You’ll find CR2032 batteries in a wide range of car brands and models.
However, the CR2032 isn’t the only player. You might also find key fobs using:
- CR2025: Very similar to the CR2032 in diameter (20mm) but slightly thinner at 2.5mm. It offers slightly less capacity than the CR2032 but can be used in some fobs designed for CR2032 if space is a concern.
- CR2016: Again, 20mm in diameter, but even thinner at 1.6mm. Used in slimmer key fobs where space is at a premium. It has a lower capacity than both CR2032 and CR2025.
- CR1632, CR1620, CR1616: These are smaller diameter batteries (16mm) and come in thicknesses of 3.2mm, 2.0mm, and 1.6mm respectively. They are less common than the CR20xx series but are still found in some key fobs, particularly in certain makes like Honda. For example, the Honda CR-V sometimes requires a CR1250 battery, although this might be a less frequent type compared to the CR16xx and CR20xx series. It’s always best to double-check.
It’s also worth noting that while most key fobs use a single coin cell battery, some, like the Ford Mustang key fob, might require two batteries to operate.
How to Determine What Battery Your Key Fob Uses
So, how do you know exactly what battery your key fob uses? There are a few ways to find out:
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Check the Key Fob Case: The easiest method is to look directly at your key fob. Many manufacturers emboss the battery type directly onto the back of the fob or inside the battery compartment. Look for markings like “CR2032” or similar codes. Sometimes this information is visible without even opening the case.
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Open the Key Fob: If you don’t see the battery type on the exterior, you’ll need to carefully open the key fob. As the original article mentions, you’ll typically need a thin, flat tool like a watch knife or a small flathead screwdriver. Gently pry open the case, being careful not to force it and damage the plastic. Work your tool around the seam of the case to gradually separate the two halves.
Caution: Avoid just pulling the case apart from one point as this can easily break the plastic fasteners. Wedge your tool around the entire perimeter, gently prying as you go.
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Examine the Old Battery: Once you have the key fob open, you’ll see the battery. The battery type is always printed directly on the battery itself. This is the most definitive way to know what battery your key fob uses. Take note of the code (e.g., CR2032, CR1620) and the battery manufacturer if you wish.
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Consult Your Car Owner’s Manual: While less convenient, your car’s owner’s manual might specify the key fob battery type. However, this is not always the case, and the manual might only refer to “key fob battery” without giving the specific code.
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Online Resources: If all else fails, you can search online for your car’s make, model, and year along with “key fob battery type.” Numerous online forums, car parts websites, and battery retailers provide battery compatibility information for various vehicles.
Replacing Your Key Fob Battery: A Quick Guide
Once you’ve identified what battery your key fob uses, replacing it is a simple process. Here’s a summarized step-by-step guide, drawing from the original article’s advice:
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Gather Your Tools: You’ll need the correct replacement battery, a small pry tool (watch knife or small screwdriver), and possibly tweezers. A precision screwdriver might be needed for some fobs with small screws.
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Open the Key Fob: Carefully pry open the case as described earlier.
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Remove the Old Battery: Use tweezers or your fingers to gently remove the old battery. Note the orientation of the battery (positive side up or down) before removing it. Often, the positive (+) side faces upwards. Taking a photo with your phone at this stage is a good idea as a reference.
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Insert the New Battery: Place the new battery into the compartment, ensuring the correct orientation (positive side usually facing up).
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Close the Key Fob: Snap the two halves of the key fob case back together until they are securely closed. You should hear a click or feel them snap into place.
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Test Your Key Fob: Try using your key fob to lock and unlock your car to ensure the new battery is working correctly.
Tips for Choosing and Buying Key Fob Batteries
- Buy the Correct Type: Always ensure you are purchasing the exact battery type specified for your key fob (e.g., CR2032, CR1620). Using the wrong type can lead to poor performance or even damage your key fob.
- Choose Reputable Brands: Stick to well-known battery brands for reliable performance and longevity.
- Check Expiration Dates: Coin cell batteries have a shelf life. Check the expiration date on the packaging to ensure you are buying fresh batteries.
- Consider Buying in Multi-Packs: If you have multiple vehicles or want to have spare batteries on hand, buying batteries in multi-packs can be more economical.
Conclusion
Understanding what batteries do key fobs use and how to replace them is a small but valuable piece of car ownership knowledge. By taking a few minutes to identify the correct battery type and following a simple replacement procedure, you can restore your key fob’s functionality and avoid unnecessary trips to the dealership. Keep your key fob powered up and enjoy the convenience it provides every day.
