Replace the battery yourself in five minutes with a coin

You can change a Toyota key fob battery without tools or a trip to the dealer. Most Toyota key fobs use a coin-cell battery (usually CR2032 or CR2016) that you can buy at any pharmacy, grocery store, or hardware store for two to five dollars. The whole job takes about five minutes and requires only a coin—a dime or penny works fine.

The battery sits inside a plastic case that snaps open. You do not need a screwdriver or special equipment. Once you have the new battery, you can swap it out and have your key working again in the time it takes to read these instructions.

Key Takeaways

  • Most Toyota key fobs hold a CR2032 or CR2016 coin-cell battery that costs two to five dollars and is sold at pharmacies and grocery stores.
  • You open the fob by sliding a coin into the slot on the edge and twisting gently—no screwdriver needed.
  • Note which side of the battery faces up before you remove it, then insert the new battery the same way.
  • Test the key fob buttons before you leave the store or pharmacy to make sure the new battery works.

Find out what battery your Toyota key fob uses

The battery type is printed on the old battery itself. Open your key fob first (see the next section), take out the battery, and look at the top. You will see a code like CR2032, CR2016, or CR2025. Write this down or take a photo with your phone.

If you cannot open the fob or the battery is too worn to read, check your Toyota owner's manual—it lists the battery type for your year and model. You can also call a Toyota dealer with your vehicle identification number (VIN) and they will tell you the battery type over the phone at no charge.

Most Toyota key fobs made in the last ten years use CR2032, which is the most common size. If you are unsure, buy a CR2032 and a CR2016—they are inexpensive, and you can test which one fits.

Open the key fob with a coin

Look at the edge of your key fob for a small slot or seam. On most Toyota fobs, this slot runs along one edge. Slide a coin (a dime, penny, or quarter works) into the slot and twist gently—do not force it. The fob will pop open like a clamshell, usually splitting into two plastic halves.

If the fob does not open after a gentle twist, try the other edges. Some Toyota fobs have the slot on a different side. Once you find the right spot, the coin will slide in smoothly and the fob will separate with light pressure.

Set both halves on a clean surface where you can see them. The battery will be sitting in a small metal or plastic holder inside.

Remove the old battery and note its position

Before you touch the battery, look at which side is facing up. The side with the + symbol (positive terminal) should be facing either up or down—note this. Take a photo with your phone if it helps you remember.

Gently pry the battery out of its holder using your fingernail or the edge of a coin. Do not use a sharp tool that could damage the plastic holder. The battery should come out easily. If it is stuck, try wiggling it gently side to side.

Once the old battery is out, you can throw it away or recycle it at a pharmacy or electronics store. Do not leave it loose—batteries can leak if they are damaged.

Insert the new battery the same way

Take your new battery and place it in the holder with the positive side (+) facing the same direction as the old battery was facing. Most Toyota fobs have the positive side facing up, but check your photo or memory of the old battery to be sure.

Press the battery down gently until it sits flat in the holder. You should hear or feel a small click as it settles into place. Do not force it—if it does not sit flat, you may have it upside down.

Close the two halves of the fob by pressing them together. They should snap shut with a click. If they do not close all the way, the battery may be in the wrong position—open it again and check.

Test the key fob before you leave

Press each button on your key fob—lock, unlock, panic, trunk, or whatever buttons your model has. Each button should light up or you should hear a beep from your car. If nothing happens, open the fob again and check that the battery is sitting flat and facing the right direction.

If the buttons still do not work after you have checked the battery position, the battery may be defective. Go back to the store and swap it for another one of the same type. Defective batteries are rare, but they do happen.

Once all the buttons work, you are done. Your key fob should work normally for two to four years before the battery runs down again.

Common mistakes to avoid

The most common mistake is installing the battery upside down. The positive side must face the same direction as it did in the old battery. If your fob stops working after you replace the battery, this is the first thing to check.

Another mistake is forcing the fob open. If the coin does not slide in smoothly, you are probably using the wrong edge. Try all four sides gently before you assume the fob is stuck. Forcing it can crack the plastic and make the fob unusable.

Do not touch the battery terminals with your bare fingers if you can help it. Oils from your skin can interfere with the connection. If you do touch them, wipe the battery gently on a clean cloth before you install it.

Frequently Asked Questions

What if my Toyota key fob will not open with a coin?

Try all four edges gently—the slot may be on a different side than you expect. If none of the edges work, your fob may have a different opening method. Check your owner's manual or call a Toyota dealer. Some older models use a small screw instead of a coin slot.

Can I use a different battery size if I cannot find the exact one?

No. Using the wrong size battery can damage the fob or cause it to malfunction. Stick with the exact type printed on your old battery. If you cannot find it locally, order it online—it will arrive in one or two days and costs the same.

How long does a Toyota key fob battery last?

Most key fob batteries last two to four years with normal use. If you use your fob many times per day, the battery may wear out faster. If you rarely use it, it may last longer. You will know it is time to replace it when the buttons stop responding or respond slowly.

Do I need to reprogram my key fob after changing the battery?

No. Changing the battery does not erase the fob's programming. It will work exactly as it did before, as long as the new battery is installed correctly and facing the right direction.

What should I do with the old battery?

Take it to a pharmacy, grocery store, or electronics retailer that has a battery recycling bin. Many places recycle batteries for free. Do not throw it in the trash—batteries contain materials that should be recycled.