Another Tesla Y owner opened mine with his phone

[Foxsbiscuits]

The car will lock when you’re still within Bluetooth range, so you can’t base the range on that. If the car is locked and someone tries to open the door, it will unlock and open if the phone is still within Bluetooth range, which is what we presume happened in the OP’s case.

I don't think this is correct and it's not the case for me. I can look in the app, see my phone is connected as phone key via Bluetooth, yet I still have to be very close to my car to be able to open the doors.
You can leave your phone twenty feet away and still get in your car?
Bluetooth connection isn't locking/unlocking the car, Bluetooth proximity is and that's the bit that gets potentially garbled.

 

[EVRider-FL]

I don't think this is correct and it's not the case for me. I can look in the app, see my phone is connected as phone key via Bluetooth, yet I still have to be very close to my car to be able to open the doors.
You can leave your phone twenty feet away and still get in your car?

Yes, I just tried this with my 2023 Model S. The car is in my garage, where it normally stays unlocked. I locked it via the app, left the phone in my kitchen, went out and tried to get in the car, but that didn’t work. I moved the phone to a location about twenty feet away from the car but still inside the house, and I was able to open the car.

 

[Foxsbiscuits]

Yes, I just tried this with my 2023 Model S. The car is in my garage, where it normally stays unlocked. I locked it via the app, left the phone in my kitchen, went out and tried to get in the car, but that didn’t work. I moved the phone to a location about twenty feet away from the car but still inside the house, and I was able to open the car.

Interesting and very surprising. Model S may have a different setup? Would be interested to test that with a different make of phone to see if it changes anything. Could you also drive it or just open doors?

 

[kaizen099]

I have to be right next to my door in order for door to unlock, like right next to the door.

 

[Tam]

Interesting and very surprising. Model S may have a different setup? Would be interested to test that with a different make of phone to see if it changes anything. Could you also drive it or just open doors?

That's the convenience of BT, you don't need the phone inside your car to drive away.

If your BT is within range to allow opening doors, that's good enough to drive away without the phone inside the car.

If the BT doesn't unlock your doors, its signal is not sufficient to drive away (you can lock someone in the car first and test the outside signal effectiveness.)

 

[Foxsbiscuits]

That's the convenience of BT, you don't need the phone inside your car to drive away.

If your BT is within range to allow opening doors, that's good enough to drive away without the phone inside the car.

If the BT doesn't unlock your doors, its signal is not sufficient to drive away (you can lock someone in the car first and test the outside signal effectiveness.)

Ok, to me that's not the convenience of this function and I can't imagine use cases where I'd want it to behave like that.
The fact I have to be touching my car for it to work is the convenience+security I want.
One time I left phone in the kitchen about ten metres away whilst I washed car, I pressed too hard on the windscreen and set the alarm off

 

[Tam]

Ok, to me that's not the convenience of this function and I can't imagine use cases where I'd want it to behave like that.
The fact I have to be touching my car for it to work is the convenience+security I want.
One time I left phone in the kitchen about ten metres away whilst I washed car, I pressed too hard on the windscreen and set the alarm off

Ok. It might not be the convenience you are looking for, but BT allows anyone to open your car and drive away without your phone inside.

It might not be convenient, but it can explain how a stranger can drive your car away while you are outside of your car distracted nearby.

 

[zoomer0056]

Please, serious replies only. Thanks

Strangest thing. I was at a restaurant with some friends, of whom one person owns an identical black 2023 Y standard model like myself. He had to leave early while the rest of us were still there. I get a phone call from this friend who said " Guess what? So bizarre! I'm inside your car right now. I got in thinking it was mine then I saw your name on the screen." My car was clearly locked. So the next time I saw him, I tried opening his car with my phone and sure enough, I was able to! He stood far in distance to make sure that it wasn't his phone that activated the unlock. Although I wasn't able to start the car, it's alarming knowing someone can enter my car and steal belongings or tamper with it.

Any idea how this can happen and how to fix it?

We haven't had a thread like this to debunk in quite awhile.

 

[ucmndd]

Just noticed this in the current app update, relevant to OP’s concern:

 

[Iron]

This happened to me at a hardware store. Another MY owner opened my hatch with his phone when he went to load stuff in his. Luckily I was walking out to the car when it happened. It was pouring rain so we didn't stop to discuss it.

 

[Calliope]

I accidentally opened someone else's MY that happened to be parked behind mine on the street and was the same colour as mine. I left them a note on their dashboard, and started using the PIN to drive option because of that. If I could do it to them, someone else could do it to me. https://teslamotorsclub.com/tmc/threads/i-opened-another-tesla-by-mistake.273542/

 

[zoomer0056]

Just noticed this in the current app update, relevant to OP’s concern:

View attachment 1015122

What is motion and fitness permision?

 

[Foxsbiscuits]

I accidentally opened someone else's MY that happened to be parked behind mine on the street and was the same colour as mine. I left them a note on their dashboard, and started using the PIN to drive option because of that. If I could do it to them, someone else could do it to me. I opened another Tesla by mistake!

I mean, maybe this is possible but it sounds unscientific and anecdotal. Maybe it wasn't locked or they had left a phone key in the car or they set it to remain unlocked at home.
I'm not discounting this idea completely I'm just not properly convinced. There's other things that could be happening that make it look like you're opening someone's car with your phone.

 

[zoomer0056]

What is motion and fitness permision?

Never mind, look here

Tesla Explains Why the Tesla App Wants Access to 'Motion & Fitness Activity'

Why is Tesla asking for access to your Activity? Tesla's app update 4.27.5 includes enhanced phone key with motion detection for improved security

www.notateslaapp.com

 

[mborkow]

What is motion and fitness permision?

Tesla Explains Why the Tesla App Wants Access to 'Motion & Fitness Activity'

Why is Tesla asking for access to your Activity? Tesla's app update 4.27.5 includes enhanced phone key with motion detection for improved security

www.notateslaapp.com

You can access that setting under the Tesla app settings in the iOS Settings app (rather than from the Tesla app itself). However if you are walking towards your car and your phone is in range, then it would not prevent someone else from walking up to your car and opening it...if you are really concerned: disable phone key or require pin to drive.

 

[EVRider-FL]

Interesting and very surprising. Model S may have a different setup? Would be interested to test that with a different make of phone to see if it changes anything. Could you also drive it or just open doors?

I’ll try it with my wife’s 2023 Model Y later and let you know, but I’m guessing it will be the same.

 

[Johnny Vector]

It's probably not by design, but determining distance via RF signal strength is a tricky guessing game. There are dozens (hundreds?) of different phones out there (across two major operating systems), and 10-20 major variations of Tesla vehicles that support phone key.

It would be a miracle if the exact distance to allow unlocking were anywhere near consistent. No way Tesla can thoroughly test and tune thousands of permutations of hardware accurately.

And that's not even considering how buildings, cars and other objections in between phone and car interfere with this.

This! It's important to understand that "Bluetooth range" is not a thing. (To be pedantic, I'm fairly sure Tesla doesn't even use "Bluetooth", it uses "Bluetooth Low Energy", which is different, although it uses the same frequency range.)

Bluetooth and BLE operate at ~2.4 GHz, which has a wavelength of ~12 cm (~5 inches). That means any metal bits larger than a couple inches in any dimension will reflect or diffract the radio waves. So the answer to, for instance, "Does BLE work through walls?" is "Depends what's in the wall." For a wood-frame house, the answer is probably yes. For a commercial establishment like a store or a restaurant, the answer is somewhere between "yes" and "no". Are the walls metal? How many cars are between you and your car? And what about that row of conduits you can't see? To the BT waves, it looks like a diffraction grating, so if you move a foot in the right direction you can go from perfect reception to none at all.

The point is that whether your BT key works depends on a lot more than distance.

 

[gsmith123]

I wonder if Tesla uses the GPS location as a secondary input to the distance estimation as well. Both the car and phone have GPS (and on the phone end various other methods like wifi triangulation). Under good conditions both can be quite accurate (down to 10-15 ft or so), precise enough that it could be a meaningful second independent input to the distance estimation.

 

[Johnny Vector]

I wonder if Tesla uses the GPS location as a secondary input to the distance estimation as well. Both the car and phone have GPS (and on the phone end various other methods like wifi triangulation). Under good conditions both can be quite accurate (down to 10-15 ft or so), precise enough that it could be a meaningful second independent input to the distance estimation.

The problem is when GPS fails it can fail pretty badly. Like in much of lower Manhattan (and other skyscrapery cities), there's so much multipath from all the buildings that GPS will regularly put you 100 feet from your actual position.

Also, inside parking garages is not good for GPS reception. Although at least there you know there's no signal so you could ignore the GPS entirely.

Seems like a lot of trouble to make it work reliably. If it ended up as reliable as, say, the auto windshield wipers, it would just make things worse.

 

[EVRider-FL]

Interesting and very surprising. Model S may have a different setup? Would be interested to test that with a different make of phone to see if it changes anything. Could you also drive it or just open doors?

I was able to unlock my wife's Model Y with the phone key in the house, as with my Model S, but I wasn't able to drive it. The irony is that sometimes it takes a few attempts to unlock the cars even with the phone key right next to the car.