Experiencing issues with your 2015 Toyota Corolla key fob? It can be frustrating when your key fob suddenly stops working. Recently, I encountered a similar problem with a replacement key fob for my Corolla, and what started as a simple battery swap turned into a valuable lesson about key fob batteries.
Initially, one of my new key fobs ceased to function. My first thought was the battery. Upon checking the voltage of the no-name Chinese battery it came with, my voltmeter read 2.5v. Reasoning that a fresh battery would solve the issue, I grabbed one of my “fresh” Panasonic CR2016 batteries, which I had purchased online a few years prior but were still within their expiration date of 12/2022 and tested at 3.3v. However, to my surprise, the key fob remained unresponsive.
Puzzled by this, I re-checked the voltage of the Panasonic battery after attempting to use it in the fob – still 3.3v. Everything pointed to the battery being good, yet the fob was dead. On a whim, I asked my wife to pick up a brand-new Energizer CR2016 battery from the store. Skeptical but willing to try anything, I installed the new Energizer battery, and to my astonishment, it worked! Even more surprising, all four of my key fobs, including the ones I thought were working fine, now operated perfectly with new batteries.
The key takeaway from this experience is crucial for any 2015 Corolla owner dealing with key fob issues: don’t solely rely on voltage readings or expiration dates to determine if a coin battery is good. Like car batteries, these small CR2016 batteries can appear to be functional based on voltage alone, but they may fail under load. My “fresh” Panasonic batteries, despite showing a good voltage and expiration date, were apparently no longer capable of providing sufficient power to operate the key fob.
This experience also taught me a valuable storage lesson. Buying batteries in bulk might seem economical, but storing them for extended periods, even if they are unused and within their expiration date, can lead to performance issues. Moving forward, I plan to purchase CR2016 batteries only when needed, ensuring freshness and optimal performance for my 2015 Corolla key fobs.
While initially suspecting a more complex issue, the solution was as simple as using a truly new battery. On the bright side, this troubleshooting adventure did lead me to explore Toyota Techstream software. While resolving the key fob battery issue, I also gained valuable experience using Techstream and even programmed a few custom options for my car. Plus, I’m now prepared for future TPMS sensor replacements when their batteries eventually require changing. Every problem, even a seemingly minor key fob battery issue, can present a learning opportunity!
And if anyone is interested in purchasing some slightly used, but voltage-verified, Panasonic CR2016 coin cells (expiration 12/2022), let me know! 😉
