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Is the keycard nfc?

Is the keycard nfc?

Is the keycard regular NFC? Can it be "copied" to a cell phone? Plenty of Android apps let you read and write NFC.

Coastal Cruiser. | 25. helmikuu 2018

The question of whether the key card is NFC (Near Field Communications) or RFID (Radio Frequency ID) has been batted around this forum a bit... with no resulting firm answer to the best of my knowledge.

Having said that, it is assumed that the data stream -albeit one-way or two-way between the card and the readers in the car- is likely to be encrypted, so one would not expect that you could copy/clone a Model 23 key card.

But then we didn't think you could open the frunk with a 9v battery when the 12v battery still had a charge. So it will be interesting to see the results when someone inevitably tries to clone a key card.

Coastal Cruiser. | 25. helmikuu 2018

Model 23 > Model 3. We're still in 2018. I was standing to close to the Atavachron.

EVRider | 26. helmikuu 2018

According to the manual, the key card is RFID.

andy.connor.e | 26. helmikuu 2018

RFID my friend.

Haggy | 26. helmikuu 2018

If it had been NFC, perhaps it could have been cloned. That would have allowed you to use your phone as a key, as opposed to using the app after a one time procedure where you tap the card to the car.So the advantage would have been that you would have tapped the card to the phone for on time setup instead of tapping it against the car? The advantage/ problem is that you wouldn't need to be near the car to clone a key.

With the current method, a valet can't clone the key without credentials for the app. Nobody can clone it away from the car. I don't see any reason to change it since the disadvantages outweigh the advantage

Frank99 | 26. helmikuu 2018

NFC is an extension of RFID. They use the same concepts and powering mechanisms, and the frequency that NFC uses is the same as one of the standard RFID frequencies. It is perfectly valid to call an "NFC device" an "RFID Device", but not always valid to call an "RFID Device" an "NFC Device".

NFC was created to provide:
1. A very short range operation - a couple of cm. This means that intercepting the communications is extraordinarily difficult.
2. Standardized cryptography and security, so that two devices can always communicate securely.
3. Standardized two-way communications, allowing for cryptographically secured payment schemes.

Tesla probably chose RFID in order to have a longer range of operation. Placing the card in the cup holder is great, but is unlikely to keep the card within a couple centimeters of the reader. By choosing RFID and building their own security on top of that (probably based on the NFC specs), they can extend range up to 10's of cm and make the card easier to use. Note that it's possible with RFID to have ranges greater than 25 meters.

Coastal Cruiser. | 26. helmikuu 2018

Good points Frank. If the presumption that NFC cards can be cloned but RFID cards cannot , then attempting to clone the key card might be revealing. Revealing to us nerds who for some reason happen to care... and as well to see if the darned card can be copied. :>

Carl Thompson | 26. helmikuu 2018

NFC is a subset of RFID. Just saying that the key cards are RFID does not answer the question.

Carl Thompson | 26. helmikuu 2018

Ninja'd by @Frank99

EVRider | 26. helmikuu 2018

@Carl: The Model 3 Owner's Manual just says RFID, so that's the only answer we have. If it was also NFC, I'm guessing the manual would have said so, but I don't really know. The manual does say the key must be an inch or two from the reader to be read, so it's short range either way.

andy.connor.e | 26. helmikuu 2018

Seems like RFID and NFC are relatively the same. Only difference i have read, is that NFC typically has another step associated with it such as sending information to another source. Such as scanning your credit card to make a financial transaction. The NFC basically does an "RFID" scan of the card, and the NFC would bluetooth it or cell-internet it to the financial institution.

But technically what @CT said is true, because they are relatively the same.

Neuman.ben | 26. helmikuu 2018

Looks like NFC. FCC filing here includes picture of what looks like an AS3915 NFC IC
https://fccid.io/2AEIM-1089774/Internal-Photos/Internal-Photos-3491731

Coastal Cruiser. | 26. helmikuu 2018

Brilliant.

But what chip are you referring to? The large chip labeled 'CC2640' seems to be the Bluetooth chip.

Coastal Cruiser. | 26. helmikuu 2018

Wait. I see it.

Frank99 | 26. helmikuu 2018

And the frequency range noted (13.56-13.56 MHz) is what NFC uses....

Coastal Cruiser. | 26. helmikuu 2018

Reading about this 'AS3915 NFC IC' chip... not necessarily a surprise, but it contains a EEPROM chip (pronounced 'double eprom'). It stands for Electrically Erasable Programmable Read Only Memory. I've heard owners speak of getting their key cards programmed to their car at a Tesla Service Center. It's likely that programmable memory chips is what enables that. Very convenient.

Coastal Cruiser. | 26. helmikuu 2018

So frank, that full sized antenna they are using might be what allows for the card to be placed a ways away from the reader.

Frank99 | 26. helmikuu 2018

Yup.
If it's NFC, and has two-way communications, the EEPROM would store a secret that the car and card agree on that would be used to authenticate the card to the car. And, yes, getting it programmed is when that secret gets exchanged and stored.

Tesla2018 | 26. helmikuu 2018

I'm lost by how this stuff works but if you owned several Model 3's would it be possible to use the same card on all of them? Similar to having one key to start all the cars you own instead of having to have different keys for each one?
Me and my siblings all use the same garage door 4 digit code and have our houses keyed the same to avoid having to have a bunch of keys and codes to remember when we visit each other. When we grew up it was a pain to find everyones keys if we had to move cars out of the driveway since the town wouldnt let you park on the street or take out a curb to widen your driveway to be able to have cars parked side by side.

Coastal Cruiser. | 26. helmikuu 2018

It makes sense for your garage door and house keys, but do you have any fobs that unlock the doors on all your cars?

Perhaps someone with two Model 3s will chime in, but it seems a long shot.

EVRider | 27. helmikuu 2018

You can’t use one key card for multiple cars, but you can use one phone for multiple cars if all the cars are associated with the same account.

Frank99 | 27. helmikuu 2018

Technically, your scheme is perfectly reasonable and do-able, Tesla2018. The question is whether or not Tesla thought about that case when they designed the system and allowed for it.

Daryl | 27. helmikuu 2018

Will the card work if left in a wallet that is placed next to the pillar? (I assume yes, normally.)

What if the wallet has "NFC Shielding"? (I assume no.)

1102445954 | 24. syyskuu 2018

Nfc is the best solution, it makes us more convenient. We are a rfid solution provider and if you are interested you can visit us: https://www.starnfc.com

1102445954 | 24. syyskuu 2018

Nfc is the best solution, it makes us more convenient. We are a rfid solution provider and if you are interested you can visit us: https://www.starnfc.com

greg | 18. heinäkuu 2019

Does RFID fabric block NFC? Maybe it doesn't, and that's why my 2016 MX goes thru a battery about every 15 days. Fob is kept in QUADRUPLE lined RFID wallet kept just inside garage door, about 6 feet away. Car shuts off, or appears to, as soon as I close the wallet. A Tesla fob tech did say (a few months ago) that he could see the car and fob still communicating - in spite of the car being 'off'!! Anyone heard of that? I haven't been able to reach him again. He quit returning my calls.