Just like any other battery-powered device, your car key fob relies on a small battery to function. If you’ve noticed your key fob becoming less responsive, or requiring multiple button presses to lock or unlock your doors, the culprit is likely a dying battery. Knowing What Battery Is In A Key Fob is the first step to a simple and cost-effective fix you can often do yourself.
Understanding the type of battery your key fob uses is essential for a quick replacement. While it might seem like a trip to the dealership is necessary, the truth is, replacing a key fob battery is usually a straightforward process. This guide will walk you through identifying the right battery for your key fob and how to replace it, saving you time and money.
Identifying Your Key Fob Battery Type
The most common type of battery found in car key fobs is a coin cell lithium battery. These small, round batteries are known for their longevity and power, making them ideal for compact devices like key fobs. However, not all key fobs use the same size or type of coin cell battery. Determining the correct battery is crucial before you attempt a replacement.
Here are a few ways to figure out what battery is in your key fob:
-
Check the Key Fob Casing: Many key fobs have markings directly on the case indicating the battery type. Look closely at the back of your key fob or under the battery compartment cover. You might find embossed letters and numbers like CR2032, CR1620, or similar.
-
Consult Your Owner’s Manual: Your vehicle’s owner’s manual is a valuable resource. It often includes information about key fob maintenance, including the specific battery type required for your key fob. Check the index or the section on keys and remote entry.
-
Open the Key Fob (Carefully): If you can’t find the battery type externally, you’ll need to open the key fob. This should be done gently to avoid damaging the internal components.
Common Key Fob Battery Types
While there are various types, some coin cell batteries are more commonly used in key fobs than others. Knowing these common types can help you narrow down your search:
-
CR2032 Battery: This is perhaps the most prevalent key fob battery. It’s a 3V lithium coin cell known for its long life and is used in a wide range of car makes and models.
-
CR2025 Battery: Slightly thinner than the CR2032, the CR2025 is another 3V lithium battery you might find in your key fob.
-
CR1632 Battery: This 3V battery is smaller in diameter and thinner than the CR2032 and CR2025. It’s often used in slimmer key fob designs.
-
CR1620 Battery: Another 3V option, the CR1620 is even thinner than the CR1632 and is suitable for very compact key fobs.
-
CR2450 Battery: Larger in diameter and thicker than the other types listed, the CR2450 is a 3V battery that provides a longer lifespan and is used in some key fobs requiring more power.
It’s important to note that while CR2032 is very common, specific car manufacturers and models may use different batteries. For example, as mentioned in the original article, some Honda CR-V models use a CR1250 battery. Always double-check to ensure you get the correct replacement. Some Ford Mustang key fobs even require two batteries.
Step-by-Step Guide to Replacing Your Key Fob Battery
Once you know what battery is in your key fob and have the replacement ready, you can proceed with the battery replacement. Here’s a general guide based on the original article’s instructions, with added detail for clarity:
Tools You’ll Need:
- New Key Fob Battery: Make sure you have the correct type and size.
- Small Flathead Screwdriver or Watch Knife: For carefully prying open the key fob case. A thin blade is ideal to minimize damage.
- Precision Screwdriver Set (1.4mm – 2.4mm): Some key fobs have tiny screws that need to be removed.
- Tweezers (Optional but Recommended): To handle the battery, especially in tight spaces.
- Your Smartphone Camera: To take pictures as you disassemble the fob, for reference.
Steps:
-
Prepare Your Workspace: Work on a clean, well-lit surface. Having a soft cloth underneath can prevent scratches to the key fob and help contain any small parts.
-
Open the Key Fob Case: Examine your key fob case. Look for a small notch or seam. This is usually where you can insert your flathead screwdriver or watch knife to begin prying it open.
- Gently Wedge and Twist: Insert the blade into the notch and gently twist or wedge to start separating the case halves. Work your way around the seam, applying gentle pressure. Avoid forcing it open at one point, as this can damage the plastic clips holding it together. Think of it like carefully peeling an orange, as the original article suggests.
-
Take a Picture! Before you remove anything, use your phone to take a clear photo of the inside of the key fob, especially the battery orientation and any small components. This is a crucial step, as key fob interiors can vary, and this photo will be invaluable when reassembling.
-
Remove the Old Battery: Carefully remove the old battery. In some fobs, the battery is held in place by a small clip or friction. You might need to use tweezers or your fingertip to gently lift it out. Note the orientation of the battery – usually, the positive (+) side is facing up, but your photo will confirm this.
-
Insert the New Battery: Place the new battery into the compartment, ensuring the correct orientation (positive side up or down, as per your photo and the markings in the battery compartment). Make sure it sits securely in place.
-
Reassemble the Key Fob: Carefully snap the two halves of the key fob case back together. Press firmly until you hear or feel them click into place. If you removed any screws, re-insert and tighten them gently.
-
Test Your Key Fob: Try locking and unlocking your car doors with the key fob to ensure the new battery is working correctly.
Important Tips and Cautions
- Gentle is Key: Always handle the key fob and its components with care. Forcing anything can lead to damage and the need for a complete key fob replacement.
- Static Electricity: While not as sensitive as some electronics, it’s good practice to ground yourself by touching a metal object before handling the circuit board to minimize static electricity risk.
- Battery Orientation: Double-check the battery orientation before inserting the new one. Incorrect orientation won’t damage the fob, but it won’t work.
- Avoid Touching Circuitry: As the original article advises, avoid touching the circuit board or any wiring inside the key fob. Focus solely on the battery replacement.
- If in Doubt, Seek Professional Help: If you are uncomfortable opening your key fob or are unsure about any step, it’s always best to seek assistance from a professional at a dealership, car repair shop, or battery center.
Conclusion
Knowing what battery is in a key fob empowers you to take control of a common car maintenance task. By identifying the correct battery type and following these simple steps, you can easily replace your key fob battery yourself, saving time and money compared to dealership service. With a fresh battery, your key fob will be back to reliably locking and unlocking your car, ensuring convenience and security. Remember to check your local battery retailers or online for replacement batteries to keep your key fob powered and working perfectly.
