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Still confused how to keep the car locked properly

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Sanny

Member
Jul 7, 2013
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1,268
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6 month in and still confused about the car self-locking functionality:
1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range. How to prevent it? I think someone can even start driving it that way.
2) Often I come to the car that was parked somewhere and open the trunk manually (by pressing the physical button on the trunk) and it opens fine. Then I approach the door to open it and it is still closed and goes sentry mode on me. Confused - was the trunk even closed while I was out?
 
If your phone is in the house the car should be locked. I park in my garage, don't even get all the way in the door to the house and the car locks. My gripe is it locks too dang fast. I'd rather it didn't lock at all when I'm at home. Seems if it can fold the mirrors in automatically when I get home it should also be able to leave the car unlocked at home location.
 
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6 month in and still confused about the car self-locking functionality:
1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range. How to prevent it? I think someone can even start driving it that way.
2) Often I come to the car that was parked somewhere and open the trunk manually (by pressing the physical button on the trunk) and it opens fine. Then I approach the door to open it and it is still closed and goes sentry mode on me. Confused - was the trunk even closed while I was out?


When you walk away and are about 30 feet away you should be able to hear an audible tone and to observe the side mirrors fold inward. This is audible and visual confirmation that the car is locked.
 
6 month in and still confused about the car self-locking functionality:
1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range. How to prevent it? I think someone can even start driving it that way.
2) Often I come to the car that was parked somewhere and open the trunk manually (by pressing the physical button on the trunk) and it opens fine. Then I approach the door to open it and it is still closed and goes sentry mode on me. Confused - was the trunk even closed while I was out?
After 6 months you haven’t thought to leave your phone in the house and try to open door or drive? Do you really have the car?
 
So based on the answers I assume I haven't missed a hidden option or something. Probably will need to disable bluetooth if my phone is in the part of the house close to the car.
 
OP - you can change the behavior of how your car locks, etc.

pps 8-9 in the manual:
Authenticated Phone
Using your phone is the most convenient way to access your Model 3. As you approach, your phone's Bluetooth signal is detected and doors unlock when you press a door handle. Likewise, when you exit and walk away with the phone, doors automatically lock (provided the Walk-Away Door Lock feature is turned on, as described in Walk-Away Door Lock on page 13).

Before you can use a phone to access Model 3, follow these steps to authenticate it:
  1. Download the Tesla mobile app to your phone.
  2. Log into the Tesla mobile app using your Tesla Account user name and password.
    Note: You must remain logged in to your Tesla Account to use your phone to access Model 3.
  3. Ensure that your phone's Bluetooth setting is turned on.
    Note: Model 3 communicates with your phone using Bluetooth. To authenticate your phone or use it as a key, the phone must be powered on and Bluetooth must be enabled. Keep in mind that your phone must have enough battery power to run Bluetooth and that many phones disable Bluetooth when the battery is low.
  4. Ensure that Allow Mobile Access (Controls > Safety & Security > Allow Mobile Access) is enabled.
  5. In the Tesla mobile app, touch PHONE KEY then touch START to search for your Model 3. When your Model 3 is detected, the mobile app asks you to tap your key card.
  6. Tap the key card against the Model 3 card reader on the door pillar or center console (see Key Card on page 8).
When Model 3 detects your key card, the mobile app confirms that your phone has been successfully authenticated. Touch DONE.

If the key card is not successfully scanned within approximately 30 seconds, the mobile app displays an error message. Touch PHONE KEY on the app again to retry. To view a list of keys that can currently access Model 3, or to remove a phone, touch Controls > Locks (see Managing Keys on page 10).

Note: Authenticating your phone allows you to use it as a key to access Model 3. To use the phone hands-free, access your phone's contacts, play media from it, etc., you must also pair and connect to it using the Bluetooth settings (see Phone on page 116).

Note: Model 3 can connect to three phones simultaneously. Therefore, if more than one phone is detected and you want to use, or authenticate, a different phone, move the other connected phone(s) out of range or turn off its Bluetooth setting.

Note: Unlike the mobile app, once a phone has been authenticated, it no longer requires an internet connection to communicate with Model 3. Authenticated phones communicate with Model 3 using Bluetooth. Keys Opening and Closing 7

Note: Although Bluetooth typically communicates over distances of up to approximately 30 feet (9 meters), performance can vary based on the phone you are using, environmental interference, etc.

Note: If multiple vehicles are linked to the Tesla Account, you must switch the mobile app to the Model 3 that you want to access before you can use the phone as a key.

pg 13...
Walk-Away Door Lock
Doors and trunks can automatically lock whenever you walk away carrying your authenticated phone. To turn this feature on or off, touch Controls > Locks > Walk-Away Door Lock.

When the doors lock, the exterior lights flash once and the mirrors fold (if equipped with the premium package and Fold Mirrors is on). To also hear a confirmation sound whenever Model 3 locks, touch Controls > Locks > Lock Confirmation Sound > ON.

Model 3 does not automatically lock if:
  • An authenticated phone is detected inside Model 3.
  • You are not using an authenticated phone as the key and walk away carrying the key card or key fob. When using the key card you must manually lock Model 3 by tapping the key card against the door pillar. When using the key fob (sold as an accessory), you must manually lock Model 3 by pressing the lock button. See Keys on page 7.
  • A door or trunk is not fully closed.
Note: If all doors are closed and Model 3 was automatically unlocked by your authenticated phone, walk-away locking is temporarily suspended for one minute. If you open a door within this minute, it will not re-lock until all the doors are closed and you have walked away with the authenticated phone.
 
1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range. How to prevent it? I think someone can even start driving it that way.

Have you actually tried this? I tried it and have my phone inside the house. The app showed that my key status as "Connected", but leaving the phone where it was, I went out to try the doors and they did not unlock. Even though you are in Bluetooth range, it doesn't mean the doors can be unlocked without the phone being a foot or 2 next to door.

2) Often I come to the car that was parked somewhere and open the trunk manually (by pressing the physical button on the trunk) and it opens fine. Then I approach the door to open it and it is still closed and goes sentry mode on me. Confused - was the trunk even closed while I was out?

I pretty much do this every morning. If your car goes sentry mode on you, maybe there is something wrong with your car?
 
...1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range...

Yes and no. That depends.

Someone has made the experiment:

"11-12 feet on either side, 0 feet in front, and 21-23 feet in the rear."



...How to prevent it?...

Just turn off your phone's Bluetooth.

Set up your PIN to Drive.

...I think someone can even start driving it that way...

Yes. I did that (drove off without a fob or signal inside) since 2012 with my former Model S and it's still true with X, 3 depending on how close the signal is.
 
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I beamforming is used and it knows the distance from the multiple Bluetooth antennas in the car. I have to be within a few feet or the doors won't open even if my key is connected. My kid always runs to the car ahead of me and the door won't unlock until I get a few feet away.

Here is an interesting video that is somewhat relevant to this conversation.

 
Yes and no. That depends.

Someone has made the experiment:

"11-12 feet on either side, 0 feet in front, and 21-23 feet in the rear."





Just turn off your phone's Bluetooth.

Set up your PIN to Drive.



Yes. I did that (drove off without a fob or signal inside) since 2012 with my former Model S and it's still true with X, 3 depending on how close the signal is.
Have you actually tried this? I tried it and have my phone inside the house. The app showed that my key status as "Connected", but leaving the phone where it was, I went out to try the doors and they did not unlock. Even though you are in Bluetooth range, it doesn't mean the doors can be unlocked without the phone being a foot or 2 next to door.



I pretty much do this every morning. If your car goes sentry mode on you, maybe there is something wrong with your car?
Yes, when I test it specifically it stays closed with my phone in the closest to the car place in the house and Connected status. However, it was not once or twice when kids pulled the door of the car that was supposed to be closed and it did open fine for them with my phone being inside the house. Ok, so I need just to decide how paranoid I want to be with that and either use pin to drive or stop worrying.
 
I was doing some car stuff in the garage. In this garage, I pull forward into it. I closed the door, walked to the front of the car, the car locked doors (lights and audio confirmation). I placed the phone on a shelf that is in front of the car (so car, about 18 inch gap, then shelf). I walked back to open the car to get something and door (driver's side) remained locked. I had to pick up the phone and walk back to the car to have it unlock.

Anyway, I never really looked into it because it wasn't an issue for me (garage and house are not too close). Maybe the app looks at movement of the phone and if it senses phone is sitting idle for a while, then it shouldn't unlock even if close by.
 
I started to use PIN as soon Tesla offered it in one of the updates. It doesn't take much effort at all!

Tesla started to offer the PIN for a reason.

This video is before the offer:



FWIW the hack in that video never existed for the model 3- it was only for older Teslas with weak encryption that has since been significantly improved anyway
 
6 month in and still confused about the car self-locking functionality:
1) When the car in the driveway and the phone is in the house anyone can come to the car, pull the handle and open the door because the phone is in range. How to prevent it? I think someone can even start driving it that way.
2) Often I come to the car that was parked somewhere and open the trunk manually (by pressing the physical button on the trunk) and it opens fine. Then I approach the door to open it and it is still closed and goes sentry mode on me. Confused - was the trunk even closed while I was out?
I can’t even unlock my car when my phone is on the table next to the garage door (door leading to the house) and I’m 7 feet away and opening the tesla door. You phone in your house Is fine. Don’t believe me? Have someone in your house hold your phone and you try opening the car.
 
FWIW the hack in that video never existed for the model 3- it was only for older Teslas with weak encryption that has since been significantly improved anyway

1) I am not an expert but these thieves never used any encryption/decryption for Tesla at all.

They rather rely on SARA or Signal Amplification Relay Attack.

Signal Amplification Relay Attack does not try to crack any password or any encryption/decryption at all!

It only amplifies the signals between the car and the fob as if the fob and the car are next to each other and not at a distance far away.

2) I think there's another time-consuming method in fob cloning that works better to crack simple encryption and especially if that encryption is static.

It's just like the older automatic garage opener. Its encryption was simple and static. Hackers could decipher that static encryption if giving them enough time.

Thus, newer automatic garage openers now have a rolling encryption which makes deciphering it harder because by the time the hackers successfully crack the last encryption, a new encryption is now rolled on and hackers have to restart the deciphering process again.

I don't think there's any report of this kind of method from Tesla thieves but researchers have demonstrated that it's possible so Tesla has responded to these researchers by implementing Rolling Encryption recently.

However, fixing method #2 has no effect on method #1 Signal Amplification Relay Attack as method #1 does not want to take time to get involved with encryption/decryption at all.

Thus, you can use PIN to deal with both method #1 and #2 because even with method # 1 that is quick without cracking the encryption from the signals but thieves have to figure out the PIN. But if you give the thieves enough time, they will finally crack the static 4 digit pin code (10,000 possible combinations) with their fingers someday.
 
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