6 days - that's how long the fob battery lasts

[geordi]

This is repeatable with THREE different fobs now, the latest one is BRAND NEW from a service center and I've now gotten just about exactly a week out of each battery. I've been writing the date on them when installed. Fresh genuine Panasonic batteries from Amazon. I'll allow that the first one from the service center was unknowable on the quality, but that one only made it 5 days.

WTAF is going on here? Yes I'm using the car extensively and daily, but when car camping I'm also trying to put the fob into a faraday bag so that it has a chance to sleep - if I don't (or the cheap chinesium box didn't properly isolate) then the car will unlock itself and wake me up with the chirping computer every couple hours. Why it takes around 2 hours and THEN decides to unlock, is another mystery.

I REALLY wish they had stayed with something that used normal RF instead of this always-on-and-not-at-all-LOW-energy bluetooth. Or gave us a system with an actual power switch on the thing. Putting it in the magic places in the X (2016) also does not seem to make it read with the battery out - so that's another fun trick. If I don't have a stack of batteries in the console at all times, I get that lovely and un-dismissable alert on the screen like it is as important as an airbag warning. It's a fecking battery. WHY is it like this?

 

[Ostrichsak]

Potentially related: there's a massive amount of battery counterfeit going on on Amazon. Because of that, I only buy from the actual seller such as Duracell, Energizer, Panasonic, etc.

If you're going on Amazon and buying the cheapest but it's some 3rd party seller this could be the root of your issues.

 

[scottf200]

faraday bag

I had a 2016 Sig P90DL X and I recall there being a problem with the fob battery draining. I thought there was a software fix. Before that I was putting my fob in an old altoid 'tin' can but it sure seems like your faraday bag would work even better. When road tripping, I carry a spare fob wrapped in tin foil in an altoid can within my glove box.

I agree with the above poster about potentially getting bad batteries. I 100% had that trouble with some Amazon purchased batteries as well and ended up buying them locally. I always carry spare fob batteries in my glove box since that time in Custer SD after doing a 'dog and pony' show during the meetup and a hail storm was headed our direction ... and my fob battery died. Such a strange size as well as they couldn't be found locally. Another X owner had a spare fob and gave me the battery out of it.

 

[scottf200]

I recall there being a problem with the fob battery draining. I thought there was a software fix.

This could be what I'm recalling (2016 X)

https://static.nhtsa.gov/odi/tsbs/2016/SB-10081843-5448.pdf

 

[geordi]

This could be what I'm recalling (2016 X)

https://static.nhtsa.gov/odi/tsbs/2016/SB-10081843-5448.pdf

But that TSB seems to only be requesting replacement of the batteries, and this car has current firmware. So that doesn't seem like a solution at all?

 

[scottf200]

But that TSB seems to only be requesting replacement of the batteries, and this car has current firmware. So that doesn't seem like a solution at all?

I'm sorry for the confusion. I was quoting myself and showing what I recalled as a problem back then ... not now.

It is certainly the HW design back then. I would think that with *known* good batteries and a faraday bag or more (test with tinfoil + altoid can or faraday bag?) to see what your battery life is.

You can take your battery out daily at the same time and use a volt meter to test it as well and see if it is going down with a pattern.

 

[Ostrichsak]

One more thing: keep your fob well away from your vehicle when not in use. I read where someone kept their fobs by the back kitchen door and the distance was just close enough that it would constantly communicate with the car but also far enough that it took more effort to do so. The result was constantly dead batteries.

In addition to sourcing batteries from known quantities, we keep our fobs on our dressers in our bedroom. The issue cleared up for us with these precautions taken.

 

[Les236]

I am not that familiar with the bluetooth fobs, but you want to keep the Tesla fobs away from other devices, and I would check your phones and tablets that they are not always in a mode to be searching for bluetooth devices. This could cause the fob to be constantly awake.

 

[dandelot]

Get one of those fob pockets that are a metal (invisible wires) cage.
Put the fob in it while at home. No signals will get into the fob, nor
will it be sending signals. With the fob in its 'pocket' you can take
it right to the car and the car won't 'see' it.

Search for 'key fob protector' and look for the words 'faraday cage'
in the description. I see a usual option is a 2-pack
for around $10.

 

[GNFO]

Not really sure what the problem is, but I feel like it's particular to your car/fob. We have two Model Xs (2017/2018) with a total of four fobs, and I'd say we go a good 2-3 years between battery changes. No special steps taken to preserve battery life.

 

[geordi]

Not really sure what the problem is, but I feel like it's particular to your car/fob. We have two Model Xs (2017/2018) with a total of four fobs, and I'd say we go a good 2-3 years between battery changes. No special steps taken to preserve battery life.

Now that's very interesting - and not at all my experience with any of the three fobs I have. Right now I'm operating only with one having the battery in, and I just got a new faraday bag. Going to put the key in it at night when sleeping and see if that changes the lifespan. I'm on a road trip and car camping with it right now, so 24/7 the key is in the car. That SHOULD NOT kill it that fast, and it shouldn't be constantly communicating if it isn't moving location in the car anyway.

 

[GNFO]

Now that's very interesting - and not at all my experience with any of the three fobs I have. Right now I'm operating only with one having the battery in, and I just got a new faraday bag. Going to put the key in it at night when sleeping and see if that changes the lifespan. I'm on a road trip and car camping with it right now, so 24/7 the key is in the car. That SHOULD NOT kill it that fast, and it shouldn't be constantly communicating if it isn't moving location in the car anyway.

Well, admittedly I can't attest to what would happen if the fobs were actually IN the car full time. At night the closest one is about 30ft away through the garage wall. The others are further away, but the battery life has been similar across all 4, including the two spares that don't get used much.

 

[JBT66]

This is very interesting. My fob dies all the time, it sits about 15 feet away. My wife’s hasnt had an issue in the last 2 years. Hers is usually in the bed room 60 ft away from the vehicle. Perhaps I need to move it further away.

 

[metroplex]

Not a model X but my 2022 M3LR has been having issues with the key fob recently. It worked fine/flawlessly when I first got the car new last September and the new fob. But some updates over the winter (I had stored the car for 6 months) must have caused the fob to glitch out more frequently because it no longer works as it should:

Tesla brand Model 3 fob - battery lifespan?

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...

teslamotorsclub.com

 

[geordi]

When I'm traveling and using the X 24/7 in camping mode or (obviously) as a car, the key is always in the car since that's where I am too. Overnight, I have taken to keeping the key in that faraday bag. Not so that it can't communicate with the car (which it can't) BUT so that the dang doors stay locked!

With the key in the cupholder or anywhere else - and not moving - the MCU will chime and unlock the doors after some random amount of time around 2 hours. Clearly this is either the key "waking itself up" and transmitting on its own, or the car sending out a signal and the key responding that it is within the detection range. I don't know which, but I suspect it is the car as that has more power available... But why ~2 hours, and when the car is in camping mode, so it isn't going to sleep or powering anything off?

The other keys I have are disassembled (no batteries) and staying in the faraday bag. I HAD thought that maybe the bluetooth tracker (Tile) that I had on my keychain was causing the fob to stay awake and transmitting constantly... But I'm not sure of that right now since I stopped using that and the next two batteries STILL only lasted a little more than a week. I'm also not convinced that it isn't somehow counterfeit batteries / near-dead in the package.... But since this is such a rare style, I'm limited on where I can purchase them without the risk of getting something that has been sitting in a package for a VERY long time collecting dust.

It is NOT a solution, but I suppose that if the batteries from Amazon are half dead and only last a week or two when I'm using the car daily and extensively.... At least they are cheap at under $2 each. But this is the ONLY car and battery that I have had this kind of problem with. What a terrible design.

 

[Gumball]

Totally not normal behavior, unless indeed the batteries arrive half empty. You use gloves or something to install the battery? If not, touching them while installing can drain them incredible quick.

 

[metroplex]

I've had to replace CR2032 batteries in many other devices (firearm optics, etc) and never used gloves. Your fingers would have to be soaked in some conductive solution to really drain the batteries that quickly but I understand the concern as the cathode/anode are really closely spaced.

 

[geordi]

Yeah, I don't wear gloves and I'm not handling them with C3-PO's conductive fingers either. But I'm also only touching them for maybe 20 seconds, it doesn't take long to pick it up, angle it into the pocket and press down.

After changing EIGHT of them in the last two months, I've gotten really fast at it. I still have all the old ones, one of these minutes I will pull out my meter and check them.

I just got another package of four from Amazon, so I plan to meter these and mark the bags (really kinda sketch packaging on this one, the last batch WERE in Panasonic blister pack, but those were the ones not lasting long. So I want to see where I'm starting from on these.

 

[metroplex]

Costco sells 2032s in bulk at a decent price and they are of good quality

 

[geordi]

Costco sells 2032s in bulk at a decent price and they are of good quality

So does everyone else - the problem is that the Model X doesn't use those. It uses a goofy size, 2354 which are twice as thick and have a step in the outer diameter.