What Battery Your VW Key Fob Uses and Where to Buy It

Most Volkswagen key fobs use a CR2032 coin cell battery, a flat round battery about the size of a dime. Some older VW models use CR2025 or CR2016 instead, so check your owner's manual or the battery compartment itself before you buy. You can find CR2032 batteries at any drugstore, supermarket, electronics retailer, or online — they cost between $3 and $8 for a pack of two or four.

Before you open the fob, look at the back or sides for any markings that tell you which battery it takes. If you cannot find markings, open the fob first (see the next section) and look at the old battery itself — the size is printed on it. Taking a photo of the old battery with your phone makes it easy to match when you shop.

Key Takeaways

  • Volkswagen key fobs almost always use CR2032 batteries, which you can buy at any drugstore for $3 to $8.
  • Most VW fobs open by sliding a small lever or prying gently at a seam with a flathead screwdriver or coin.
  • The battery sits in a metal holder; note which side faces up before you remove it, then insert the new one the same way.
  • After you close the fob, test all buttons — lock, unlock, trunk, panic — to confirm the new battery is working.
  • If the fob still does not work after a new battery, the problem is likely the circuit board or buttons, not the battery itself.

Opening the Key Fob Without Damaging It

Most VW key fobs open one of two ways. The first is a small metal or plastic lever on the edge or back of the fob — slide it sideways or pull it outward, and the fob splits into two halves. If you do not see a lever, look for a thin seam running around the edge of the fob. Use a flathead screwdriver, a coin, or a plastic pry tool to gently work the seam open, starting at one corner and working your way around.

Do not force it. If the fob is not opening easily, you are likely prying in the wrong spot or using too much pressure. Stop, look again for a lever you might have missed, and try a different edge. Forcing the fob can crack the plastic housing or damage the circuit board inside.

Once the fob splits, you will see the battery sitting in a metal holder. The holder has a small lip or edge that you can use to lift the battery out. Some holders have a spring underneath the battery; if yours does, note which end of the spring is touching the battery so you can put it back the same way.

Removing the Old Battery and Installing the New One

Lift the old battery out of its holder using your fingernail or the edge of a plastic tool. Do not use a metal screwdriver directly on the battery itself, as this can damage it or create a short circuit. Once the battery is out, look at which side was facing up — the side with the + symbol or the flat side — and remember this orientation.

Before you insert the new battery, check that the metal holder and the contacts inside the fob are clean and dry. If you see any corrosion (a white or green crusty buildup), gently wipe it away with a dry cloth or a cotton swab. Corrosion can prevent the new battery from making good contact.

Insert the new battery into the holder with the same side facing up as the old one. The battery should sit flat and snug in the holder. If there is a spring underneath, make sure it is positioned the same way it was before. Close the fob by pressing the two halves together until you hear or feel a click, or slide the lever back into place if your fob has one.

Testing the Fob After Battery Replacement

Press each button on the fob — lock, unlock, trunk release, and panic if your model has one — and watch your car to confirm it responds. The car should lock and unlock smoothly, and the lights should flash or the horn should sound when you press panic. If all buttons work, the battery replacement is complete.

If some buttons work and others do not, the problem is likely worn contacts or a damaged circuit board, not the battery. If no buttons work at all, double-check that the battery is inserted the right way around (+ side up, usually) and that the fob is fully closed. Open it again and reseat the battery, making sure it sits flat in the holder.

What to Do If the New Battery Does Not Fix the Problem

If you have installed a fresh CR2032 battery and the fob still does not work, the issue is inside the fob itself. The most common causes are worn rubber button contacts, a cracked circuit board, or corrosion on the internal contacts that a new battery cannot fix.

At this point, you have two options: buy a replacement key fob from a Volkswagen dealer, an automotive locksmith, or an online retailer, or have a locksmith reprogram an aftermarket fob to your car. Dealer fobs are more expensive but may provide to work; aftermarket fobs are cheaper but require programming. A locksmith can usually do both the sale and programming in one visit.

Frequently Asked Questions

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

No. CR2032, CR2025, and CR2016 are different sizes and voltages. Using the wrong size can damage the fob or not fit in the holder at all. Buy the correct battery for your model — it takes five minutes to find at any store.

How often do I need to replace the battery?

A CR2032 battery in a key fob usually lasts three to four years with normal use. If you use the fob heavily or leave it in a hot car, it may drain faster. Replace it as soon as you notice the buttons responding slowly or the car not locking from a distance.

What if I lose the two halves of the fob while it is open?

Keep both halves in front of you on a clean surface while you work. If you drop a piece, do not panic — it is just plastic. Pick it up, inspect it for cracks, and continue. The pieces are not small enough to lose easily unless you are working over a sink or outside.

Is it safe to replace the battery myself, or should I go to a dealer?

Replacing the battery yourself is safe and takes about two minutes. You do not need special tools or training. A dealer will charge $50 to $100 for the same job. Save your money and do it at home.