Most Hyundai key fobs use a CR2032 coin battery that you can swap yourself in under a minute

Your Hyundai key fob runs on a small coin-shaped battery, usually a CR2032, that sits behind the plastic case. You can open the fob, remove the old battery, and install a new one without tools or a trip to the dealer. The whole job takes about 30 seconds once you have the new battery in hand.

The battery type varies slightly by model year and fob design, but CR2032 is the standard across most Hyundai vehicles from the last 15 years. You can buy a CR2032 at any drugstore, grocery store, or hardware store for a few dollars. Some Hyundai dealerships will also swap the battery for you at no charge, though you will save time doing it yourself.

Key Takeaways

  • Hyundai key fobs almost always use a CR2032 coin battery, which you can buy at any pharmacy or supermarket for a few dollars.
  • The fob case opens by sliding a small metal lever or prying gently at the seam with a coin or flat tool — no screwdriver needed.
  • When you install the new battery, the flat side faces up and the ridged side faces down, sitting in the metal contacts at the bottom of the case.
  • If the fob still does not work after you install a fresh battery, the problem is likely the circuit board or buttons, not the battery itself.

Identify your fob type and battery before you start

Open your glove box or check your owner's manual to confirm your fob model. Hyundai uses two main designs: a flip-key fob (where the key blade slides out) and a push-button remote. Both use CR2032 batteries, but the way you open them differs slightly.

If you have lost your manual, you can also look at the back of the fob itself. Many Hyundai fobs have a small slot or seam that shows where the case splits. Some models have a tiny metal lever stamped into the plastic. Take a photo of your fob before you go to the store so you can show the clerk exactly what battery you need — they will confirm it is the right one.

Open the fob case without damaging the plastic

Look for a small slot or seam running along the edge of the fob. If your fob has a metal lever (a thin stamped piece on the back), slide it gently in the direction of the arrow to pop the case open. If there is no lever, use a coin — a dime or penny works well — and insert it into the seam at the edge. Turn the coin slowly to pry the two halves apart.

Work around the entire seam if the case does not pop open on the first try. The plastic is designed to split at that line, so you should not need to force it. If you are worried about scratching the fob, wrap the coin in a thin cloth or use a plastic spoon handle instead of metal. Once the case cracks open, you can pull the two halves apart by hand.

Remove the old battery and note its position

Inside the fob you will see a small round battery sitting in a metal holder or slot. The battery has a flat side and a ridged side. Look at which way it is facing — the flat side should be pointing up toward you, and the ridged side should be touching the metal contacts below. This matters when you install the new one.

Gently pry the old battery out with your fingernail or a plastic tool. Do not use a metal screwdriver or anything sharp, because you can damage the metal contacts inside the case. Once the old battery is out, set it aside. If the battery looks corroded or leaking, wipe the inside of the case gently with a dry cloth before you install the new battery.

Install the new CR2032 battery the correct way

Take your new CR2032 battery and hold it so the flat side faces up. Slide it into the metal holder, flat side up, until it sits flush. The ridged side will rest against the metal contacts at the bottom. Press down gently to make sure it is seated — you should hear or feel a small click.

Do not force the battery. If it does not slide in smoothly, flip it over and try again — you may have had it upside down. Once the battery is in place, the fob is ready to close. You do not need to do anything else inside the case.

Close the case and test the fob

Line up the two halves of the fob so the seam runs straight. Press them together firmly until they snap. You should hear a click or feel the case lock. If your fob has a metal lever, slide it back to the closed position.

Test the fob by pressing each button — lock, unlock, and panic if your model has one. Stand a few feet from your car and press the lock button. You should see the lights flash or hear the locks click. If nothing happens, open the fob again and check that the battery is seated correctly, with the flat side facing up. If the fob still does not work after you reseat the battery, the problem is likely inside the circuit board or the buttons, not the battery itself.

When to replace the battery again

A CR2032 battery in a key fob usually lasts between three and four years, depending on how often you use the fob. You will notice the range getting shorter — you have to stand closer to the car for the buttons to work — before the fob stops working entirely. When that happens, follow the same steps to swap in a fresh battery.

Keep a spare CR2032 in your car or at home so you are not stuck if the battery dies when you are away from a store. They are inexpensive and last a long time on the shelf, so buying two or three at once makes sense.

Frequently Asked Questions

Can I use a different battery size if I cannot find a CR2032?

No. CR2032 is the correct size for Hyundai fobs, and using a different battery can damage the contacts or not fit in the case at all. CR2032 batteries are widely available and inexpensive, so it is worth waiting a day or ordering one online rather than substituting.

What if the fob still does not work after I put in a new battery?

Open the fob again and check that the battery is sitting flat with the correct side facing up. If it is, the problem is likely a broken button, corroded contacts, or a damaged circuit board. At that point, a dealership can repair or replace the fob, or you can buy an aftermarket replacement online.

Is it safe to open the key fob myself?

Yes. The fob case is designed to open and close by hand, and there are no electrical hazards inside. The only risk is scratching the plastic if you use a sharp tool, so use a coin or plastic tool instead of a screwdriver.

How do I know if my battery is dead or if something else is wrong?

If the fob worked fine and suddenly stopped, the battery is the most likely culprit. If the fob has been weak for weeks and the range keeps shrinking, the battery is definitely dying. If you install a fresh battery and the fob still does not work, the problem is the fob itself, not the power source.