You can replace a Honda key fob battery yourself in about two minutes with a coin
Most Honda key fobs use a coin-cell battery — typically a CR2032 or CR2025 — that you can swap out without tools or a trip to a dealer. The battery sits behind a removable cover on the back of the fob. You pry the cover open with a coin or flat object, lift out the old battery, drop in a new one with the correct side facing up, and snap the cover back. The whole job costs between $3 and $8 for the battery itself.
The exact steps depend slightly on which Honda model and fob design you own, but the principle is the same across nearly all of them. This guide covers the most common fob types. If your fob looks different — for instance, if it has a sliding battery door instead of a hinged one — the process is even simpler.
Key Takeaways
- Honda key fobs almost always use a CR2032 or CR2025 coin-cell battery that you can buy at any pharmacy, grocery store, or hardware store for $3 to $8.
- The battery compartment is on the back of the fob and opens by prying a seam with a coin, flathead screwdriver, or butter knife — no special tools needed.
- The battery must go in with the correct side facing up: the flat side (marked with a plus sign) faces toward you when you look into the compartment.
- After you replace the battery, test the fob by pressing each button to confirm it works before you leave the store or put the old fob away.
Identify which battery your Honda fob uses
Before you buy a replacement, you need to know which battery is inside. The easiest way is to open the fob and look at the old battery itself — the model number is printed on top. Most Honda fobs use either a CR2032 (the most common) or a CR2025. Both are the same diameter but slightly different thicknesses; a CR2032 is slightly thicker.
If you do not want to open the fob first, you can check your owner's manual or search online for your specific model year and fob type. Honda's website also lists battery types by model. When you go to buy the battery, bring a photo of your fob or the model number from your manual so the store employee can confirm you have the right one.
Do not guess or buy both types. Using the wrong battery can cause the fob to malfunction or fail to hold a charge properly.
Locate the seam and pry open the battery compartment
Turn the fob over so the back is facing you. Look for a thin seam running around the edge or across the middle of the back cover. This seam is where the two halves of the fob meet. You will insert a coin or flat tool here to pry them apart.
Use a coin (a dime or penny works well), a flathead screwdriver, or a butter knife. Place the edge of your tool into the seam and gently twist or pry. Do not force it — the cover should pop open with light pressure. If it does not budge, try a different spot along the seam; sometimes one side is easier to start than the other.
Once the cover begins to separate, you can usually pull it the rest of the way by hand. Set the cover aside in a safe place so you do not lose it.
Remove the old battery and insert the new one
Inside the compartment, you will see the coin-cell battery sitting in a small metal holder or slot. It is usually held in place by a slight lip or groove. Gently pry it out with your fingernail or the edge of your tool. The battery will pop out easily once you lift one edge.
Before you insert the new battery, check the orientation. The battery has two sides: a flat side marked with a plus sign (positive) and a rounded side (negative). The flat side should face toward you — toward the outside of the fob — when you look into the compartment. Slide the new battery into the slot with the flat side up, and it should click or seat into place.
If the battery does not sit flush or feels loose, you may have it upside down. Flip it and try again. Once it is seated correctly, it should not move when you gently shake the fob.
Close the fob and test all buttons
Align the two halves of the fob and press them together firmly until you hear or feel a click. The seam should close evenly all the way around. If one side does not close flush, open it again and check that the battery is seated properly and that no plastic tabs or wires are in the way.
Once the fob is closed, test every button: lock, unlock, panic, and trunk (if your fob has one). Press each button several times and listen for the click or beep from your car. If all buttons work and your car responds, the battery replacement is complete. If a button does not work, open the fob again and confirm the battery is facing the correct direction.
Where to buy a replacement battery
CR2032 and CR2025 batteries are sold at nearly every pharmacy, grocery store, and hardware store. Common retailers include CVS, Walgreens, Target, Walmart, Home Depot, and Ace Hardware. You can also order them online from Amazon or eBay. A single battery usually costs $3 to $8; multi-packs are cheaper per unit if you want spares.
Buy a name-brand battery (Duracell, Energizer, Panasonic, or Sony) rather than a generic or off-brand version. Cheap batteries often die faster and may not hold a consistent charge. If you are unsure which brand to choose, ask the store employee — they can recommend a reliable option.
What to do if the fob still does not work after replacing the battery
If you have replaced the battery and tested it but the fob still does not work, the problem is usually one of three things: the battery is in upside down, the fob has a deeper problem (like water damage or a broken button), or the car's receiver needs to be reset.
First, open the fob again and double-check that the battery is facing the correct direction — flat side up. If it is correct and the fob still does not work, try a different new battery in case the first one was defective. If a second battery does not work, the fob itself may be damaged and you will need a replacement from a Honda dealer or a third-party fob supplier.
If the fob works but your car does not respond, the issue is with the car's receiver, not the fob. In that case, you may need to reprogram the fob. Instructions for reprogramming vary by model year; check your owner's manual or contact a Honda dealer for the steps specific to your car.
Frequently Asked Questions
Can I use a different battery type if I cannot find a CR2032?
No. Using a different battery type can damage the fob or cause it to malfunction. CR2032 and CR2025 are not interchangeable with other coin-cell batteries. If your store is out of stock, order online or try another store. The battery is inexpensive and widely available.
How long does a Honda key fob battery last?
A typical CR2032 or CR2025 battery lasts three to four years with normal use. If you use your fob frequently (multiple times per day), the battery may last only two to three years. If you use it rarely, it may last longer. Replace it as soon as you notice the fob is not working reliably.
Is it safe to replace the battery myself, or should I go to a dealer?
It is completely safe to replace the battery yourself. The process involves no electrical risk and no special knowledge. A Honda dealer will do it for you, but they usually charge $20 to $50 for the service, whereas you can do it for $3 to $8 and five minutes of your time.
What should I do with the old battery?
Most retailers that sell batteries also accept old batteries for recycling. Take the old battery back to CVS, Walgreens, Home Depot, or another store and ask where to drop it off. Do not throw it in the trash. Many communities also have battery recycling programs; search online for "battery recycling near me" to find a drop-off location.
Will replacing the battery erase my car's settings or require me to reprogram the fob?
No. Replacing the battery does not erase any settings or require reprogramming. The fob will work exactly as it did before once the new battery is installed. Reprogramming is only necessary if the fob stops working even after you have replaced the battery.