how long did your key fob battery last? mine only last 4 mos from everyday driving, I would expect to last a little longer than 4 mos.

 

That seems like a short time but you've prompted me to put a spare in the glove box. I've only had ours a month, but the NX200t we had lasted at least 6 months, whichI always calendared to switch out after having a battery failure out of town.

 

We've had ours almost 7 months and they're fine.

 

My battery also didn’t last more than a few months. I think this is due to the key connecting the profile with the vehicle as opposed to just unlocking doors, starting car, etc.

 

How were you notified that the battery needed to be replaced? I’m going on 7 months.

 

Mine last about 9 months

 

What model of battery does it take? Better look for deals now lol

 

CR2032

https://www.amazon.ca/AmazonBasics-CR2032-Lithium-Coin-Cell/dp/B0787K2XWZ/ref=sr_1_5?keywords=Amazon+Basics+4+Pack+CR2032+3+Volt+Lithium+Coin+Cell+Battery&qid=1669246599&qu=eyJxc2MiOiIyLjcwIiwicXNhIjoiMi41NyIsInFzcCI6IjIuMjgifQ%3D%3D&sr=8-5

 

FYI, for the key fob, the replacement battery type is specified in the "Electronic key battery" section of the "6-3. Do-it-yourself maintenance" subchapter of the Owner's Manual.
For those who also have the SmartAccess card key, the battery is a CR2412 lithium battery. Other than looking at what is installed in a SmartAccess card key, I haven't found any official Lexus user documentation specifying the replacement battery type to use for the card key.
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You might have it close enough to your car that it’s constantly talking to it and burning up juice. I keep mine in a faraday box when home and it lasted over a year. The spare is in the house in a faraday bag and I still haven’t gotten a message (in nearly two years) to replace the battery even though I pull it out every few months to check. You might want to use a faraday box.

 

On my 2019 ES350, I got intermittent messages on the Multi Information Display (MID) shortly after shutting off the vehicle. I can't remember the exact wording, but it was something like "Key battery low. Replace key battery" or something like that. (Intermittent because there was an interval of no messages between the first seen occurrence of the "Key battery low" message and the next seen occurrence of the message. I don't know whether the no message interval was due to a message was displayed but escaped my noticing it as I was exiting the vehicle or there was some factor affecting the key fob's battery level to intermittently be not good.)

In the Lexus app, there's a "Key Fob" status under an ES vehicle's "Health" information display. If you select "Vehicle Health Report", the health report has a "SMART KEY BATTERY STATUS" entry stating "Smart key battery level is XXXX." where XXXX is "good" if the battery level is acceptable. The app also has a "PREDICTIVE ALERTS" option under account "Notification Settings" which is supposed to issue a notification of a maintenance due item which might include smart key battery replacement needed.

I don't really know how the Lexus app "Key Fob" status works in practice nor exactly which key fob battery status is reported when multiple key fobs are paired with a vehicle and are actively in use. My experience has been either getting a MID "Key battery low." message or a seldom used key fob wouldn't unlock my ES because the key fob's battery was dead as the means of finding out I needed to replace the key fob battery.

 

My 2019 ES seldom used spare key fob battery lasted 3½ years before the battery got to the point where the vehicle would not unlock even when the key fob was right next to a door handle antenna. (The key fob was in battery saving mode only for one or two relatively short intervals.)

 

You should get a pop up on the dash display. Also, even after you replace it, the dash pop up might not go away for a couple weeks. Was a little annoying but you have to wait it out. My dealer was going to charge over $250 to look into turning it off.

 

mine is still going after 2 years.

Is your key next to your garage? Car might be constantly detecting your key and waking it up.

As others have mentioned, try putting fob in a Faraday box or hold the Lock buttong and press Unlock twice to put the fob to sleep (car won't detect the key until you press a key on the fob)

 

Most of our customers get a year to two years out of a key battery. The ones that need them sooner I tell them to store the key farther away from the car when not in use.