Lexus key fob batteries typically last three to four years before they need replacement
Your Lexus key fob runs on a coin-cell battery — usually a CR2032, CR2025, or CR2016 depending on your model year. When the fob stops locking or unlocking your car from a distance, or only works when held very close to the vehicle, the battery is almost certainly dead. Replacing it takes about five minutes and costs between $3 and $8 for the battery itself.
You do not need to visit a dealership for this repair. Any pharmacy, grocery store, or hardware store sells replacement batteries in the watch and electronics section. You can also order them online. The only tool you might need is a small flathead screwdriver, though many fobs open by hand or with a coin.
Key Takeaways
- Lexus key fob batteries are standard coin-cell types (CR2032, CR2025, or CR2016) sold at drugstores and hardware stores for a few dollars.
- You can replace the battery yourself in about five minutes without special tools or a trip to the dealership.
- The correct battery type for your fob is printed on the old battery or listed in your owner's manual.
- After inserting the new battery, test the fob before you leave home to confirm the replacement worked.
Finding the correct battery type for your Lexus model
The easiest way to know which battery your fob needs is to open it and look at the old battery itself. The type is stamped directly on the cell — you will see something like "CR2032" or "CR2025." Write down that number before you go to the store, or take a photo of it.
If you cannot open the fob or the old battery is damaged, check your owner's manual. The manual lists the battery type in the key fob section, usually near the back. Lexus also publishes this information on their website by model year, though you will need your VIN (vehicle identification number) to look it up.
If you are still unsure, call a Lexus dealership parts department with your model year and they will tell you over the phone. You do not have to buy from them — this information is free.
Opening your key fob safely
Most Lexus fobs open one of two ways. The first is a small slot or seam on the edge where the two halves meet. Insert a flathead screwdriver or coin into the slot and gently twist to pry the fob apart. Do not force it — if it does not budge after gentle pressure, try a different edge.
The second method is a small button or lever on the back or side of the fob. Press or slide it and the fob will pop open. Check your owner's manual if you cannot find it — the exact location varies by model year.
Once the fob is open, you will see the battery sitting in a small metal holder. Note which side is facing up (the positive or negative side). This matters when you install the new battery.
Removing the old battery and installing the new one
Gently pry the old battery out of its holder using a fingernail or the edge of a coin. Do not use a sharp tool that could damage the holder or the circuit board underneath. Set the old battery aside — you can recycle it at most pharmacies and electronics stores.
Before you insert the new battery, check the orientation of the holder. Most Lexus fobs have a small plus sign (+) or minus sign (−) printed on the metal holder to show which side should face up. The positive side of the battery (the flat side with the number stamped on it) should face up toward the plus sign.
Slide the new battery into the holder with the correct side facing up. It should sit flat and snug. Do not force it — if it does not fit easily, you may have the wrong battery type or the wrong orientation.
Closing the fob and testing the new battery
Once the battery is in place, close the two halves of the fob back together. If it opened with a twist, twist it back closed until you hear a small click. If it opened with a button or lever, press or slide it back into place. The fob should feel solid and not rattle.
Before you leave home, test the fob by standing a few feet from your car and pressing the lock and unlock buttons. You should hear the car respond or see the lights flash. Try it from different distances — a working fob will work from 20 to 30 feet away, depending on your model year.
If the fob still does not work after you have installed a fresh battery, the problem may be something other than the battery itself. The circuit board inside may be damaged, or the fob may need reprogramming. In that case, contact a Lexus dealership.
What to do with the old battery
Coin-cell batteries contain small amounts of lithium and other materials that should not go in the trash. Most drugstores, including CVS and Walgreens, have a battery recycling bin near the pharmacy counter or customer service desk. Home Depot and Lowe's also accept batteries for free recycling.
Some communities have hazardous waste collection days where you can drop off batteries along with other items. Check your city or county website for the schedule and location nearest you.
When to replace your key fob battery again
A new battery typically lasts three to four years in normal use. You will know it is time to replace it again when the fob only works from very close range, or when you have to press the button multiple times to lock or unlock the car. Some newer Lexus models have a low-battery warning light on the dashboard, though this is not standard across all years.
Keep a spare battery at home so you are not caught without a working fob. They are cheap and take up almost no space. You can also keep a spare fob in your car or bag — Lexus sells replacement fobs, though they cost more than just replacing the battery in your existing one.
Frequently Asked Questions
Can I use a different battery type if I cannot find the exact one?
No. Using the wrong battery type can damage the fob's circuit board or cause it to malfunction. The battery type is specific to your model year. If you cannot find it locally, order it online — it will arrive in one or two days and costs the same.
What if my fob still does not work after I replace the battery?
The circuit board inside may be damaged, or the fob may need reprogramming to your car. Contact a Lexus dealership to have them test the fob and reprogram it if needed. This usually costs between $150 and $300, depending on your model year.
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 when ready once you install the new battery and close the fob. Reprogramming is only necessary if you buy a new fob or if the old one stops responding after a battery replacement.
Where can I buy a replacement battery if I do not have a car nearby?
Any pharmacy, grocery store, or hardware store sells coin-cell batteries. Target, Walmart, and Amazon also carry them. The battery costs $3 to $8 and ships quickly if you order online. Make sure you order the correct type for your fob before you buy.