Replace the battery yourself in under five minutes
You can replace a Hyundai key fob battery without going to a dealership. The process takes about three minutes and costs between $5 and $15 for the battery itself. Most Hyundai key fobs use a CR2032 coin cell battery, which you can find at any pharmacy, grocery store, or hardware store.
The steps are the same whether you have a 2015 Hyundai Elantra or a 2023 model—the fob design has remained consistent across generations. You will need only the replacement battery and possibly a small flathead screwdriver or coin to pry open the fob case.
Key Takeaways
- Most Hyundai key fobs use a CR2032 battery, which costs $5 to $15 and is sold at drugstores and supermarkets.
- You open the fob by inserting a coin or small screwdriver into the slot on the side and twisting gently until the case separates.
- The battery sits in a metal holder with a small tab; slide it out, note which side faced up, and insert the new battery the same way.
- Test the fob before you put the case back together to confirm the new battery works.
- If the fob still does not work after battery replacement, the problem is likely the circuit board, not the battery.
What battery your Hyundai key fob needs
Check your owner's manual or the back of your fob itself—most Hyundai fobs are printed with "CR2032" on the case. This is a 3-volt lithium coin cell battery, 20 millimeters in diameter and 3.2 millimeters thick. If you cannot find the marking, bring your fob to a pharmacy or battery retailer and they will identify it by sight.
CR2032 batteries are the most common coin cell sold in the United States. You will find them in the pharmacy section near the checkout, in the electronics aisle, or at the customer service counter. A single battery costs $3 to $8 at a drugstore; multipacks are cheaper per unit if you want spares.
How to open your Hyundai key fob
Look at the side edge of your fob for a small horizontal slot or seam. This is where the two halves of the case meet. Insert a coin (a dime or penny works well) or a small flathead screwdriver into the slot, positioning it so the edge of the coin or blade sits in the seam.
Twist the coin or screwdriver gently—do not force it. You should feel the case begin to separate. Rotate it a quarter turn and then try the opposite side of the fob. Work your way around the edge, twisting a little at each point, until the two halves come apart. The battery compartment will be visible inside one half of the case.
If the case is very tight, soak the fob in warm water for two minutes to soften any adhesive, then try again. Do not pry hard enough to crack the plastic.
Remove and replace the battery
Inside the fob you will see a small metal battery holder with a tab sticking out. The battery sits in this holder with the positive side (marked with a + symbol) facing up. Slide the battery out by pulling the tab gently toward you.
Before you insert the new battery, look at which side of the old battery faced up. The new battery must go in the same way. Place the new CR2032 into the holder with the positive side up, then slide it back into place. You should hear or feel a small click as it seats.
Do not touch the flat surfaces of the battery with your bare fingers—oils from your skin can reduce battery life. If you do touch it, wipe it clean with a dry cloth before inserting it.
Test the fob before closing it
Before you snap the case back together, press each button on the fob while standing near your car. The lock and unlock buttons should respond when ready—you will see the lights on your dashboard flash or hear the locks click. If nothing happens, the battery may not be seated correctly. Remove it, check that it is facing the right direction, and reinsert it.
If the fob still does not work after reinserting the battery, the problem is likely inside the circuit board, not the battery itself. In that case, you will need a replacement fob from a Hyundai dealership or a third-party fob programmed to your vehicle.
Close the fob case
Once the buttons respond, align the two halves of the case so the seam is even all the way around. Press them together firmly until you hear a click or feel them snap into place. Start at the top and work your way down, explore even pressure.
Test the buttons one more time after closing to make sure nothing shifted during assembly. The fob should work exactly as it did before the battery died.
How long a new battery lasts
A CR2032 battery in a Hyundai key fob typically lasts three to four years with normal use. Heavy use—pressing the buttons many times per day—can shorten this to two years. If you replace the battery and it dies again within a few months, the circuit board may be draining power abnormally, which means the fob itself needs replacement.
Keep a spare CR2032 in your car or at home so you are not stranded if the battery dies unexpectedly. They are inexpensive and take up almost no space.
Frequently Asked Questions
Can I use a different battery if I cannot find a CR2032?
No. CR2032 is the correct size and voltage for your Hyundai fob. Using a different battery can damage the circuit board or cause the fob to malfunction. CR2032 batteries are widely available—if one store is out of stock, try a pharmacy, supermarket, or online retailer.
What if my fob has no visible slot or seam?
Some older Hyundai fobs have a screw on the back instead of a slot. Look for a small Phillips or flathead screw, usually near the bottom of the fob. Remove it with the appropriate screwdriver and the case will come apart. The battery replacement process is the same.
Do I need to reprogram my fob after replacing the battery?
No. Replacing the battery does not erase the fob's programming. Once you insert the new battery and close the case, the fob will work when ready without any additional steps.
Is it safe to replace the battery myself, or should I go to a dealership?
It is completely safe to replace the battery yourself. The process involves no electrical risk and takes only a few minutes. A dealership will charge $50 to $100 for the same task, so doing it at home saves money and time.
What should I do with the old battery?
CR2032 batteries can be recycled. Many pharmacies and retailers that sell batteries also accept used batteries for recycling at no charge. Check with your local waste management program or call ahead to confirm drop-off locations near you.