Tesla brand Model 3 fob - battery lifespan?

[metroplex]

I bought a new Tesla fob for my 2022 M3LR last year when I got the car new, and the fob basically sat in a drawer for the winter as I wasn't driving the car. It's been roughly 6 months and have been able to drive the car now a few days without issue. Just today the fob stopped working and the car asked me to put the key card on the center console in order to drive it. I put the fob there and it recognized it. Went home and checked the battery (the Panasonic CR2032 that came with it) at 3.00 VDC which by all means should still be good I suppose. I popped a new Duracell 2032 (the bulk pack from Costco) at 3.28 VDC

I never once saw a low battery life warning about the fob, FWIW.

I was wondering if anyone knew how long the battery typically lasts in these Tesla fobs (the ones shaped like the car for the Model 3). It's in a drawer far away enough from the car that it won't recognize it or pick it up if I get into the car and work the menu without the fob on me.

I'm wondering if it was just a stale battery from the factory or if the fob really burns through batteries. I didn't use my phone as a key because I felt the Bluetooth kept sapping the battery from my iPhone SE. Might have been my imagination.

 

[Kimmi]

Same battery since December 2020.

 

[metroplex]

I noticed that even after I manually held the door button for 3 seconds to unlock all doors, once I closed the door within a few seconds the car automatically locked. Then it refused to recognize my fob and didn't acknowledge any of the buttons I pressed. I had a hunch so I walked as far away from the car as possible to break the near-field connection and then walked back towards the car. Sure enough the fob was recognized.
I bet the battery at 3.00 VDC wasn't "dead" and the same thing happened before.

I recall an update within the past 6 months that had something to do with walk-away locking or it might have been just the windows rolling up automatically. Anyone else experience something similar???

 

[heavyD]

I only got 6 months out of the battery that came with my fob which is poor. The replacement battery seems to be doing fine but I don't use the fob as much as I do my phone.

 

[metroplex]

I noticed where I normally keep my fob that the car still picks it up from time to time. I am going to try a Faraday box.

Although the other day a weird glitch happened again where the car was unlocked as I got out. I closed the door to look at the wheel then it locked by itself. It wouldn’t recognize my fob or acknowledge the button presses. It was a fresh 2032. I walked further away and came back and it worked fine.

 

[metroplex]

So it just happened again today... Came home, parked outside and went to clear the driveway. Noticed as soon as I got out of the car that I couldn't lock the car anymore. No response from the fob. Went back into the unlocked car, and it didn't detect my fob to move the vehicle. I had to place it by the cupholders to get it to detect it.

Came home, popped the 3V Duracell CR2032 (the new one that I installed late May - see above) and it was 3.03 VDC. Not the highest for a new CR2032 but not dead either. I re-inserted the same battery and it works fine now.

It's ridiculous I'd go through a battery every 2 months. Something else has to be causing this.

I even keep my Tesla fob in a faraday bag when I am not driving, so for the past 2+ months the fob gets stored in the pouch. I can verify the car doesn't pick up the fob.

Meanwhile... the CR2032 in my Ford/GM fobs will last 5-10 years....

 

[Adam3]

So it just happened again today... Came home, parked outside and went to clear the driveway. Noticed as soon as I got out of the car that I couldn't lock the car anymore. No response from the fob. Went back into the unlocked car, and it didn't detect my fob to move the vehicle. I had to place it by the cupholders to get it to detect it.

Came home, popped the 3V Duracell CR2032 (the new one that I installed late May - see above) and it was 3.03 VDC. Not the highest for a new CR2032 but not dead either. I re-inserted the same battery and it works fine now.

It's ridiculous I'd go through a battery every 2 months. Something else has to be causing this.

I even keep my Tesla fob in a faraday bag when I am not driving, so for the past 2+ months the fob gets stored in the pouch. I can verify the car doesn't pick up the fob.

Meanwhile... the CR2032 in my Ford/GM fobs will last 5-10 years....

Battery lasts years for me. I saw another thread where someones key fob was quickly running through batteries - they returned it for a new one and the issue went away. Sounds like same issue you are facing.

 

[metroplex]

Battery lasts years for me. I saw another thread where someones key fob was quickly running through batteries - they returned it for a new one and the issue went away. Sounds like same issue you are facing.

I ordered mine from Tesla last September. I am not sure they'd be able to replace it but I emailed them nonetheless.

 

[metroplex]

I decided to just go ahead and replace the battery with a fresh one and keep an eye on it. New one is 3.29 VDC and I wrote the voltage and date on it with a Sharpie. Will see how long it lasts.