It can be incredibly frustrating when your Toyota Corolla 2015 key fob suddenly stops working. You might assume the battery is the culprit, and you’d often be right. Like many, you might grab a voltmeter, test the battery, see a reading around 3V, and think it’s perfectly fine. However, as many Toyota owners have discovered, including myself, voltage isn’t the whole story when it comes to your Toyota Corolla 2015 Key Fob Battery.
The Mystery of the “Good” Battery That Doesn’t Work
I recently experienced this firsthand. One of my replacement key fobs for my Toyota Corolla decided to quit. My first thought was the battery. Popping it out and testing it with a voltmeter showed a reading of 2.5V – a bit low, especially since it was a no-name battery that came with the aftermarket key fob. Thinking I had it figured out, I reached for my stash of “fresh” Panasonic CR2016 batteries. These batteries, bought online a few years prior but with a seemingly good expiration date of 12/2022, all tested at around 3.3V on the voltmeter. Confident, I installed one in the key fob. Nothing. Still dead.
Confused, I re-checked the voltage of the “fresh” battery after attempting to use it in the fob – still 3.3V. What was going on? Luckily, my wife was heading to the store and I asked her to pick up a brand new CR2016 battery, just in case. Skeptical but willing to try anything, I installed the brand new Energizer battery when she returned. And just like that, the key fob sprang back to life! Even more surprising, all four of my key fobs now worked perfectly with new batteries.
The Lesson Learned: Load Testing is Key for Key Fob Batteries
The key takeaway from this experience is simple but crucial: don’t rely solely on a voltage test to determine if your toyota corolla 2015 key fob battery is good. Just like a car battery needs a load test to truly assess its health, coin cell batteries like the CR2016 used in your Toyota Corolla key fob can show good voltage but still fail under load. In my case, the older Panasonic batteries, despite showing 3.3V, likely couldn’t deliver enough current under load to power the key fob. The brand new Energizer, on the other hand, provided the necessary power.
This also highlights another important point: battery expiration dates and storage. While my older batteries had “good” expiration dates, storing them for several years in a garage drawer likely degraded their performance. From now on, I’ll be buying these batteries only when I need them, ensuring they are as fresh as possible for my Toyota Corolla key fob.
Choosing the Right Replacement Battery for Your Toyota Corolla Key Fob
For a 2015 Toyota Corolla key fob battery replacement, you’ll need a CR2016 3V lithium coin cell battery. These batteries are widely available at drugstores, supermarkets, auto parts stores, and online retailers. When purchasing a replacement, consider these tips:
- Brand Matters: Opt for reputable brands like Energizer, Panasonic, Sony, or Duracell for reliable performance and longevity.
- Check Expiration Date: While expiration dates aren’t foolproof, choosing batteries with a later expiration date increases the chances of getting a fresh battery.
- Buy from Reputable Sources: Purchase your batteries from trusted retailers to avoid counterfeit or old stock.
Simple Steps to Replace Your Toyota Corolla Key Fob Battery
While specific steps can vary slightly depending on your exact key fob style, the general process for a toyota corolla 2015 key fob battery replacement is usually straightforward:
- Locate the small notch or opening on your key fob casing.
- Use a small flathead screwdriver or your car key to gently pry open the casing at the notch.
- Carefully separate the two halves of the key fob.
- Identify the battery. It’s usually held in place by small clips.
- Note the battery orientation (+ side up or down) before removing the old battery.
- Use your fingertip or a non-metallic tool to gently pry out the old battery.
- Insert the new CR2016 battery, ensuring the correct orientation.
- Snap the key fob casing back together, ensuring it’s securely closed.
- Test your key fob to ensure it’s working correctly.
Replacing your toyota corolla 2015 key fob battery is a simple DIY task that can save you time and money compared to visiting a dealership. Just remember that voltage isn’t everything, and a fresh, quality CR2016 battery is key to keeping your key fob working reliably. And avoid buying batteries in bulk and storing them for extended periods!
