Gravity Key Fob Battery helpful hints

[GGoose]

I just went through the key FOB hell of no response and all the other related problems. I did get a warning of low key fob battery. So I ordered new batteries and checked the outgoing bad battery voltage to the new battery voltage. Old battery was 2.85 volts. New battery was 3.23 Volts. After I replace the battery the car worked better than when I picked it up. The car is only 3 weeks old. I don't know where they source the batteries and when they load them in the key fob but I really do not think this was a new battery when I pick up the car. Lucid could probably avoid a lot of bad experiences by new owners if they would just put a new QUALITY battery in the FOB upon delivery.
Also. in a pinch the sun visor batteries are the same as the key FOB batteries so you can use those, and or, just keep a couple new ones in the car and change them every month for peace of mind.
NOW if they could just figure out how we can drive away using only our phone and get Apple Play working and a microphone for the audio that is as good as my 2023 truck we might have something!

 

[RandomDesign]

It's been talked about a lot in other threads. Not sure where they got those batteries or how long they've been sitting around but they die quickly. I replaced mine the day after I got my Gravity in December (on purpose, after seeing people have them die) and measured it at 2.9V. Put in a new one that was 3.2V and a month in it's still working fine.

 

[Smorgasbord]

FWIW, I have a Dec 2025 build, took delivery on Dec19 and have driven 1450 miles. Even though I haven't gotten a keyfob battery warning, I decided to check yofsy and it was at 2.95V, so I replaced it since I had bought 15 of them for $10 on Amazon (PowerOwl brand, which does well in Project Farm tests of other sizes). The new one read 3.25V, btw.

When my wife takes the car, she puts the fob in her purse. We were out together recently and stopped to do something. One of us got out of the car, leaving her purse in the car, did something, then came back, and the car wouldn't start, giving a "no keyfob" (or whatever) message. Shaking her purse didn't seem to fix it, but by then I had pulled out my key card and put it in the right spot and that let us drive again.

I have kept the key fob in my front right pocket, and I wonder if that makes the battery wear out faster since I move that leg to accelerate and brake, so I am continuously waking the fob up while I drive (and did a long drive for hours).

There's a spot in the center console for the fob. Does anyone know if the fob also has NFC like the key card and so can passively enable driving if placed there even if the battery is dead? That would be a nice failsafe. As it is, we both carry our key cards, and I put a spare battery with a plastic pry tool in a small ziploc bag in the glove compartment.

 

[Nunya]

I'm not convinced it's a battery quality issue.
How many days since your car first drove under its own power to when you took possession? I'm sure that whole time it had a key fob sitting in the tray. So in terms of life add that time. No?

Add to that, it seems more like a possible drain of the fob battery if it's within range of the car even when unoccupied. Some have suggested using a Faraday bag to store your fob.

 

[eelpout]

I'm not convinced it's a battery quality issue.
How many days since your car first drove under its own power to when you took possession? I'm sure that whole time it had a key fob sitting in the tray. So in terms of life add that time. No?

Add to that, it seems more like a possible drain of the fob battery if it's within range of the car even when unoccupied. Some have suggested using a Faraday bag to store your fob.

There's a spot in the center console for the fob. Does anyone know if the fob also has NFC like the key card and so can passively enable driving if placed there even if the battery is dead? That would be a nice failsafe. As it is, we both carry our key cards, and I put a spare battery with a plastic pry tool in a small ziploc bag in the glove compartment.

agreed, I don't think it's the battery brand or anything like that. even where it's "asleep" the fob is still active, it has to be for the shake sensor to work. it just idles at a higher power drain rate than we'd like.

Since the fob does have NFC (my Samsung phone's NFC tool sees it), one does wonder if that slot in the tray was intended as a sensing spot as a backup. I'll have to try the tool on that spot to see if it sees anything.

(My Rover has something like that on the steering column so when the fob battery is dead one can still hold the fob there and start the car. Of course, they also have a manual way to get in the car with a "hidden" physical key in the fob which the Lucid doesn't.)

 

[RandomDesign]

Since the fob does have NFC (my Samsung phone's NFC tool sees it), one does wonder if that slot in the tray was intended as a sensing spot as a backup. I'll have to try the tool on that spot to see if it sees anything.

Earlier revisions of the owner's manual said the key could be used as an unpowered NFC key like the cards but they removed all reference to that in the latest version. I'm pretty sure early on I saw someone from Lucid even recommend putting the key in that spot in the tray to troubleshoot the fob.

 

[bicycleguy]

For the non battery nerd the bottom line is replace your battery every month whether you need to or not.

For the nerds please read this excellent article that a forum member posted: flywing-tech Note how the pulsed use graph resembles the start of the graph above.
The weird and confusing thing about the battery is how the voltage recovers when you take the load off. At day zero I turned off the auto door unlock on approach. I don't know how long it had been on or how long the battery had been in the fob. Each square is when the fob was opened and voltage measured. So on day zero I left the battery out and measured again 5 minutes later and the voltage rose .01V. Put back in, used for a few days and then measured on day 4 along with of few times minutes later.
Most of the rest are measured in the morning, trying not to awake the fob before the measurement.

On day 40 the fob wouldn't work. I think some things were working squirrelly before that but didn't record or measure. All the rest of the squares on day forty were within 30 minutes total. The battery voltage out of the fob was rising quickly. The fob started working somewhere around 2.9V. Left in fob overnight and it worked and is still working even though I used it a lot. The up and down at the end is showing how quickly the voltage drops by the end of the day and then recovers over night but more weakly each time. Perhaps the seat reclining by itself issue I posted elsewhere earlier today was due to the fob glitching something up.

As can be seen the spare battery given to me on day zero hardly dropped as apparently these batteries have good no load shelf life.

 

[cinimar766]

FWIW, I have a Dec 2025 build, took delivery on Dec19 and have driven 1450 miles. Even though I haven't gotten a keyfob battery warning, I decided to check yofsy and it was at 2.95V, so I replaced it since I had bought 15 of them for $10 on Amazon (PowerOwl brand, which does well in Project Farm tests of other sizes). The new one read 3.25V, btw.

When my wife takes the car, she puts the fob in her purse. We were out together recently and stopped to do something. One of us got out of the car, leaving her purse in the car, did something, then came back, and the car wouldn't start, giving a "no keyfob" (or whatever) message. Shaking her purse didn't seem to fix it, but by then I had pulled out my key card and put it in the right spot and that let us drive again.

I have kept the key fob in my front right pocket, and I wonder if that makes the battery wear out faster since I move that leg to accelerate and brake, so I am continuously waking the fob up while I drive (and did a long drive for hours).

There's a spot in the center console for the fob. Does anyone know if the fob also has NFC like the key card and so can passively enable driving if placed there even if the battery is dead? That would be a nice failsafe. As it is, we both carry our key cards, and I put a spare battery with a plastic pry tool in a small ziploc bag in the glove compartment.

When I picked up my gravity, the rep specifically told us at that little spot was to charge the key fob. And she told us we'd get another fob in the mail. We didn't even ask, she just gave us the first one and said there are two fobs. The second one will just come in the mail. Now I'm reading online that you don't get two fobs and there is a battery in the fob that needs to be replaced apparently quite often. We only picked up our gravity on 1/21 and we're getting the low battery alert. It now has been driven across the country and nearly back. So I guess that explains why the key fob is dying

 

[Adnillien]

When I picked up my gravity, the rep specifically told us at that little spot was to charge the key fob. And she told us we'd get another fob in the mail. We didn't even ask, she just gave us the first one and said there are two fobs. The second one will just come in the mail. Now I'm reading online that you don't get two fobs and there is a battery in the fob that needs to be replaced apparently quite often. We only picked up our gravity on 1/21 and we're getting the low battery alert. It now has been driven across the country and nearly back. So I guess that explains why the key fob is dying

It sounds like you got some bad information from your delivery advisor. There is no good excuse for Lucid not training these people better. I am curious what studio or service center you picked up your Gravity at. If you have loaded OTA 3.4.1, you should change your fob battery and should see a lot less battery drain in the fob.

 

[cinimar766]

It sounds like you got some bad information from your delivery advisor. There is no good excuse for Lucid not training these people better. I am curious what studio or service center you picked up your Gravity at. If you have loaded OTA 3.4.1, you should change your fob battery and should see a lot less battery drain in the fob.

Seattle. And funny that you mentioned the update. Like I said, we drove across the country from Portland to Florida. We pretty much had no issues on the way there. There was small glitchy stuff with the infotainment having to press buttons more than once to get the screen to display correctly. And before our road trip the car kept saying offline in the app, but that fixed itself. However, they sent that email about the new update. 3.4 being rolled out, And since getting that email, (have yet to receive the update as I've not been connected to home Wi-Fi) I started getting all of the issues that were mentioned in the email. The funny thing was that we thought we had got a random update somehow. Because after a charging session once we got to Florida, our infotainment screen was slightly different and we could do different things, like the seat warmers we suddenly could choose if we just wanted the back or the butt, Which before was only both or neither. But then we started having the weird AC issue where it would sound like it was on full blast when you first start the car, but no airs coming out of the vents. It started not detecting the key fob and saying that you needed to shake it. Started having random adas glitches, like the car randomly breaking. Thinking that there's something in front of it, or the adas just completely shutting off mid use. And random other errors and warning lights that weren't actually real. Like had I not read about the 3.4 update fixing all these bugs literally less than 24 hours prior to me experiencing these bugs I would have been freaking out. But the timing was very weird. And the drive back has been frustrating, like my efficiency is lower even though the weather is pretty much the same. Like there are times where I have been going downhill and still using power instead of getting to have regen break charge my battery, Even though I've had less steep hills recharge my battery at faster driving speeds

 

[borski]

It sounds like you got some bad information from your delivery advisor. There is no good excuse for Lucid not training these people better. I am curious what studio or service center you picked up your Gravity at. If you have loaded OTA 3.4.1, you should change your fob battery and should see a lot less battery drain in the fob.

You should also check and see if the fob needs a software update, which you can do through the mobile app.

 

[borski]

like the seat warmers we suddenly could choose if we just wanted the back or the butt, Which before was only both or neither.

This has been there since the beginning; first day I got the car.

But then we started having the weird AC issue where it would sound like it was on full blast when you first start the car, but no airs coming out of the vents. It started not detecting the key fob and saying that you needed to shake it. Started having random adas glitches, like the car randomly breaking. Thinking that there's something in front of it, or the adas just completely shutting off mid use. And random other errors and warning lights that weren't actually real.

You need 3.4. Once you get it, update the fob software with the app, and then change the fob battery for a fresh one (the notes recommend this, as they’ve changed how the battery is managed).

Then you should be good to go.

 

[RandomDesign]

But then we started having the weird AC issue where it would sound like it was on full blast when you first start the car, but no airs coming out of the vents.

For this specifically, go in to the hvac control screen and if the AC button on the top is lit up toggle it off (and back on if you want it). That should fix the loud ac sound.

 

[Dr K]

I'm a little surprised nobody in this thread mentioned the battery is a 2450. What the hell? I have a dozen sizes of button batteries but had never heard of a 2450! The "larger" button batteries are all 20mm, as in 2016, 2025, 2032. My battery died while I was away on a trip (with the Gravity) so I got used to using the card key, but it's much more of a pain in the butt than the fob.

 

[borski]

I'm a little surprised nobody in this thread mentioned the battery is a 2450. What the hell? I have a dozen sizes of button batteries but had never heard of a 2450! The "larger" button batteries are all 20mm, as in 2016, 2025, 2032. My battery died while I was away on a trip (with the Gravity) so I got used to using the card key, but it's much more of a pain in the butt than the fob.

A useful tip: the visor batteries are also 2450s. In a pinch, just grab one of those.

 

[RandomDesign]

I'm a little surprised nobody in this thread mentioned the battery is a 2450. What the hell? I have a dozen sizes of button batteries but had never heard of a 2450! The "larger" button batteries are all 20mm, as in 2016, 2025, 2032. My battery died while I was away on a trip (with the Gravity) so I got used to using the card key, but it's much more of a pain in the butt than the fob.

2450s are fairly common as they're just a slightly bigger 3v with about double the capacity of the more common CR2032. I have a few things that use them other than the Gravity fob.

 

[Coyote]

The 3 Ford vehicles I had prior to the Gravity all used the 2450 cell for their fobs. It is apparently a popular size for key fob use.

 

[GGoose]

If you actually paid attention to this site you would have known that you could use your visor battery in the key fob until you found a replacement.
What the h.... indeed!

 

[bicycleguy]

I'm a little surprised nobody in this thread mentioned the battery is a 2450. What the hell? I have a dozen sizes of button batteries but had never heard of a 2450! The "larger" button batteries are all 20mm, as in 2016, 2025, 2032. My battery died while I was away on a trip (with the Gravity) so I got used to using the card key, but it's much more of a pain in the butt than the fob.

Some good battery info here https://lucidowners.com/threads/key-fob-battery-life-after-update-to-latest-firmware.14945/
Posts 7,13,17 and best 35 try to understand what is going on with the fob. Unfortunately even with 3.5.1 the info is still useful and I will be adding to it.

 

[prgarg]

If you actually paid attention to this site you would have known that you could use your visor battery in the key fob until you found a replacement.
What the h.... indeed!

... and to carry a few extra ones in the car