Keyslink
Last updated: October 20, 2023
Overviewlink
There are 4 methods of interacting with the Model 3 security system:
- Phone Key
- Near Field Communication (NFC) Key Card
- Key Fob
- Remote Access
The phone key enables passive entry and traditional remote keyless entry (RKE) features via the Tesla Tesla Mobile App on the customer's phone.
The NFC key card is a secondary means of authentication should the customer's phone not be available or not desired to be used. 2 NFC key cards can be paired with the vehicle. The key card contains passive hardware that must be presented to vehicle's key readers.
The key fob is another secondary means of authentication should the customer's phone not be available or not desired to be used. A key fob is an accessory available for purchase from the Tesla shop and does not standard with the vehicle. The key fob enables passive entry and traditional remote keyless entry (RKE). It pairs with an already-paired NFC card and communicates with VCSEC via Bluetooth Low Energy (BLE) for vehicle locking/unlocking.
Customers can use the Tesla Tesla Mobile App to remotely manage their vehicle, including locking, unlocking, and starting. Customer support can assist with these features upon customer permission. Remote access relies on the vehicle's internet connection, unlike Phone Key, NFC key card, and key fob which operate independently.
Security Controller (VCSEC)link
Vehicle security is managed by the security controller (VCSEC). Phone Key, NFC key card and key fob communicate via multiple endpoints located throughout the vehicle. Communication is secured by encryption technology between the security controller and the Phone Key, NFC key card or key fob as well as Tesla servers.
Physical Layerslink
Each method of interacting with the vehicle use a different technology. Phone key and key fob communicate via Bluetooth Low Energy (BLE) for both their passive and active features. BLE is a communication protocol that operates on a 2.4Ghz radio signal. It requires 2 active (powered) devices equipped with antennas and electronics. The key card uses Near Field Communication (NFC) to interact with a reader on the vehicle. Like other "proximity cards", NFC technology uses electromagnetic induction between the antennas of 2 NFC devices to exchange information and may even provide power to one of the devices.
The key card for the Model 3 is a passive device that is powered when placed close to the readers on the vehicle. Remote access relies on internet connectivity of both devices, typically cellular or Wi-Fi.
On the vehicle side, the security controller communicates with BLE and NFC antennas located throughout the vehicle, as well as communicating with the Infotainment system to facilitate remote access. The security controller is located in the center console behind the cup holders. It contains an integrated BLE antenna and an NFC reader. There are 3 other antennas, commonly referred to as endpoints, in the vehicle:
- LH B-Pillar below the camera
- RH B-Pillar below the camera
- Mounted to the rear bumper beam
The driver's side B-Pillar endpoint also contains an NFC reader, and is the only external NFC reader on the vehicle. The endpoints communicate via dedicated Universal asynchronous receiver-transmitter (UART) Controller Area Network (CAN) (a serial communication device) to the security controller, which communicates to the rest of the vehicle on the VEH CAN bus. The NFC reader in the center console and LH B-pillar communicates to the associated endpoint via an internal serial bus. The security controller is powered by a dedicated E-Fuse on the left vehicle controller, the LH B-Pillar and rear endpoints receive power from the left vehicle controller, and the RH B-Pillar endpoint receives dedicated power from the right vehicle controller.
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| BLE Antenna Endpoints |
- Red objects along vehicle perimeter are the endpoints, LH B-Pillar, RH B-Pillar, and Rear. The center red object is the security controller.
Note
Vehicles produced pre November 2017 have a front BLE endpoint installed. This is not active in firmware and can be disregarded.
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| Security Controller - Location |
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| 1. Green: BLE antenna 2. Red: NFC reader antenna. Note: This is only on the LH B-Pillar. 3. Orange: B-Pillar endpoint |
| LH B-Pillar Components |
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| Antenna in LH B-Pillar |
Provisioning and Key Managementlink
The first stage of securing the Model 3 is provisioning the security controller, either at the factory or in a service center, if the unit has been replaced. The provisioning process links the security controller to the VIN it is installed in and creates a record of the action with Tesla Servers, called a certificate. Tesla Servers only permit one certificate to be associated with a VIN, if a controller needs to be replaced, the provisioning process overwrites the old certificate. At present, this is critical for proper operation of phone key, which makes use of the encrypted VIN information from the certificate to successfully pair. It does not affect NFC key cards or the immobilizer.
When a phone key, an NFC key card, or a key fob is paired to the security controller, it shares an encrypted key unique to the device which is stored in a "key slot" on the security controller. There are 19 useable key slots for the customer, in any combination of phone key and NFC key card but with a maximum of 4 key fobs as long as there is at least 1 NFC key card in the system. Customers can view and manage paired keys via the User Interface (UI) and via their MyTesla account (near future scope), or by visiting Service. Keys can be assigned a set of permissions to enable activation of vehicle features. These permissions are basic in nature (such as local / remote lock and unlock ability, or ability to enter drive) and are not configurable by the customer.
Phone Keylink
Overviewlink
The Phone Key extends the capabilities of the Tesla App on compatible mobile devices to act as both a passive and active local key to the vehicle in addition to existing Remote Access features. Once paired to the vehicle, the mobile device automatically connects to the Model 3 registered to the customer's myTesla account as long as the requirements are met. The Model 3 continually advertises its identity via the 3 BLE endpoints. This advertisement is read by the Tesla Mobile App. The phone key automatically communicates with nearby Model 3 vehicles, and when it receives an encrypted challenge from the security controller, the phone key replies with its encrypted response. If the response is validated by the security controller, the vehicle is authenticated, activating passive and active features. If multiple vehicles are registered to the same myTesla account, the phone key will only connect to the actively selected vehicle.
The Model 3 automatically unlocks when the Phone Key is present, authenticated, and a door handle is pulled. Determining if the Phone Key is present is based on a signal strength threshold, which must be exceeded by at least 1 of the BLE endpoints in order to consider the Phone Key as present. Similarly, if the connected devices is determined to be leaving and Walk Away Lock is enabled, the vehicle will lock. Phone Key will authenticate the vehicle for Drive, as well as disarm the immobilizer once the vehicle determines the device is present.
Apart from the convenience of passive features, the Phone Key also supports local RKE commands via the BLE connection with the vehicle. RKE commands include locking and unlocking, and opening the front or rear trunk. Notably it excludes remote start, which is always sent via Remote Access, as the driver must step on the brake pedal to start the vehicle with a paired Phone Key present. These RKE commands use the same buttons as the Remote Access commands, offering a seamless interface to the end user. For full understanding of local RKE commands over Bluetooth, the following images show the RKE command icons in blue for those that would be transmitted over local BLE connection. The customer app WILL NOT show blue icons.
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Unique Behaviorslink
Because the Phone Key takes the place of the key fob, many of the behaviors associated with key fobs will also apply to Phone Key, such as:
- If the Phone Key is left inside the Model 3, the vehicle will remain unlocked.
- If the Phone Key is present for a period of inactivity longer than 5 minutes, the Model 3 will stop monitoring its location. It will resume if interaction with the vehicle begins again.
- If the mobile device battery dies within the 5 minute period, it would appear as if the Phone Key left the vehicle vicinity, triggering a passive lock if enabled.
- If the mobile device battery dies outside of the 5 minute period, the Model 3 would not see the Phone Key leave the vehicle vicinity. A passive lock, if enabled, would not be triggered.
- If Remote Access or an NFC key card is used to lock the Model 3 while the Phone Key is inside the vehicle, the vehicle will lock. However, the passive features will still be active and a handle pull would trigger a passive unlock.
Note
A UI lock from the interior disables passive unlock.
Pairing And Removallink
In order to initially pair the Phone Key to the vehicle, the following must be true:
- The vehicle must be associated with the customer's myTesla account.
- The customer must be signed into the Tesla Mobile App on a compatible device and have the Model 3 selected if the customer owns multiple vehicles.
- Bluetooth must be enabled on the mobile device.
- One already paired NFC key card must be present to authenticate when requested.
In order to remove a paired Phone Key, navigate to the Key Management UI via the center display. Go to Vehicle Settings → Locks. Find the device to remove, and select the Trash icon to begin the removal process. A paired NFC key card is required to remove a device, similar to the pairing procedure. A mobile device may also "forget" a vehicle Phone Key pairing by clicking the information icon next to the Phone Key line on the Tesla App, and selecting "Forget this vehicle" at the bottom. Deleting and reinstalling the Tesla Mobile App on a mobile device will delete the old identification key and pairing to the vehicle on the device. However, it will not remove the old identification key from the vehicle, and the device would have to be paired again.
Requirementslink
If the security controller is replaced, the Phone Key will need to be re-paired to the vehicle.
- Phone Key requires a mobile device that supports Bluetooth Low Energy (BLE).
- Phone Key is compatible with devices running Apple iOS 10 or later and Android v5.0 Lollipop or later.
- Phone Key is compatible with the latest version of the Tesla App.
- Bluetooth must be enabled for Phone Key operation.
- The mobile device must have been unlocked after restarting.
- The customer must be signed into the Tesla Mobile App.
- The correct vehicle must be selected or active in the Tesla Mobile App.
- For passive features, the Tesla App must have permission to run in the background.
- Android OS requires that location permissions are enabled.
- Android OS requires that location services are enabled.
Near Field Communication (NFC) Key Cardlink
The NFC key card is a durable, waterproof device that contains no power source of its own. It functions using electromagnetic induction, which facilitates wireless power transfer and communication with a powered key card reader. NFC technology requires close proximity to the reader antenna to function, usually within 4 cm. There are two NFC readers on the Model 3, one in the driver side B-Pillar applique half way down (under the camera), and the other in the center console behind the cup holders. The orientation of the NFC key card is important in order to achieve optimal detection distance and authentication time. It should be oriented vertically at the B-Pillar, and horizontally at the center console as shown. Tapping or "presenting" the NFC key card to the reader is the preferred usage method. Swiping may cause failure to complete the authentication process. Some items, such as NFC enabled cards like badges and credit cards, other metallic objects, or even a thick layer of ice and snow, can interfere with the electromagnetic field and cause severe degradation of performance. Severe bending, cracking, cutting, melting, or other mutilation of the NFC key card will cause permanent damage to the key card and may prevent proper operation. This includes a hole punch for a keyring.
Presenting the key card at either reader will authenticate the vehicle for Drive, although only presenting the key card at the B-Pillar reader will trigger a lock or unlock sequence. Authentication for Drive will expire after two minutes of inactivity, at which point the NFC key card would have to be presented to the reader again. This means that the driver only needs to present the key card to the B-Pillar reader to unlock and authenticate the vehicle for Drive. They do not need to present it again to the center console reader unless the 2 minute timer expires. If the timer does expire, the driver will receive a pop up prompt on the UI instructing them to tap the NFC card to the reader. A paired NFC key card is required in order to pair a new Phone Key for the first time.
The NFC readers on the vehicle have multiple power states to reduce power consumption and prevent unwanted interaction with NFC devices if already authenticated. The reader performance is at maximum in the Always Read power state, which it enters when it can anticipate user interaction (door handle pull for B-Pillar reader or Accessory state for center console reader) or when it attempts to read an NFC card from the low power state (Read on Wake). Pulling the driver door handle will keep the B-Pillar reader in Always Read for 20 seconds, and can improve key card authentication performance if the first attempt does not succeed.
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Pairing And Removallink
Pairing of two NFC key cards occurs at the factory and is included with every Model 3. However, additional cards can be purchased and paired if the customer desires additional cards or has lost or damaged one. In order to pair a new NFC key card, the new card must be placed on the center console reader and the pairing routine initiated. In order to remove a lost key card, the corresponding key slot must be identified and erased. Both pairing and removal processes can be performed by Service but also by customers if they have at least one NFC key card already paired to the vehicle.
Note
NFC key cards can be paired to any number of Model 3 and Model Y vehicles.
Key Foblink
The key fob is the traditional way for customers to access their vehicle and is ideal for those who do not use the Phone Key feature. It is available as an optional equipment on the Tesla Shop and includes a coin cell battery. There are two key fob generations which both offer RKE features, locking the Model 3 when pressing the key fob top area once and unlocking it when pressing twice. But only the latest generation is equipped with Passive Entry hardware, unlocking and locking the Model 3 when the key fob is within 1 meter. Both generations can also be used like a NFC key card.
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| Model 3 Key Fob |
The key fob is powered with a coin cell battery (type CR2032) and is estimated to last with normal use for around five years for the first generation and around two years for the second one. This lower battery life is due to the Passive Entry feature. If not used, it will last longer. To replace the battery, place the key fob button-side down on a soft surface and use a small flat-bladed tool to release the bottom cover. Remove the battery by gently lifting it away from the retaining clips and insert the new battery with the '+' side facing up.
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| Changing the key fob battery |
Key fobs can be paired to any number of vehicles and their NFC feature can be used at any time with any vehicle that it is paired with. The RKE and PE features only work on the last vehicle the key fob had NFC interaction with. Tapping the key fob to another paired vehicle will switch it to that vehicle.
Note
Both key fob generations are also compatible with Model Y vehicles, and can be paired to any number of Model 3 and Model Y vehicles.
Remote Keyless Entrylink
The key fob communicates via Bluetooth to the 3 BLE endpoints of the vehicle whenever one of its buttons is actuated. Radio equipment with a similar frequency can affect the key fob operation. If this happens, move the key at least 30cm away from other electronic devices.
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The three numerated buttons correspond to:
- Front trunk button
- Double-press to open the front trunk.
- Lock/Unlock button
- Single-press to lock doors and trunks (all doors and trunks must be closed).
- Double-press to unlock doors and trunks.
- Rear trunk button
- Double-press to open the rear trunk.
- Hold down for one to two seconds to open the charge port.
The key fob can also be used to prime summon the vehicle if enabled. Hold down the top button to activate prime summon, and press the frunk or trunk button to move the vehicle forward or backward after priming.
Note
Summon activation via key fob is only available in the following countries: USA, Mexico, Canada, China, Australia, New Zealand, and South Korea.
Passive Entrylink
The second generation of key fobs is equipped with Passive Entry hardware. If enabled in the vehicle security settings, the Model 3 automatically unlocks when a key fob is present, authenticated, and a door handle is pulled. Key fob presence is determined using the signal strength measured by BLE endpoints. If one the three BLE endpoints signal strength value exceeds a define threshold, key fob will be considered as present. Similarly, if a key fob is determined to be leaving and Walk Away Lock is enabled, the vehicle will lock. When present, the key fob authenticates the vehicle for drive and disarms the immobilizer.
Second generation key fobs have a built-in Inertial Measurement Unit which monitors key fob movement. The key fob will enter Sleep state after five minutes of being stationary while in range. This functionality increases the key fob battery life. Shake or press a button of the key fob to wake it up.
Reminder
First generation key fobs do not have Passive Entry hardware and are only RKE capable. If customers desire the Passive Entry feature, they should buy the latest generation key fob.
Dead Key Foblink
In the event the battery dies, the key fob can be used like a NFC key card to unlock the vehicle and authenticate for Drive. Place the key fob flat-side on the B-pillar reader to unlock the vehicle and authenticate for Drive. This will remain active for 2 minutes. If there is no activity during this time, the vehicle will need another authentication to enter Drive at either the center console or B-pillar reader.
Vehicle Behaviorslink
This section is dedicated to interpreting Tesla behavior specifications regarding vehicle security.
Authentication and Drivelink
The Model 3 will automatically immobilize and exit Drive when a drive cycle has completed, requiring an authenticated device to be present in order to re-enter Drive and disable the immobilizer. If the vehicle drives away after authenticating with the Phone Key, and no devices are detected inside the cabin, the Model 3 will display a user alert indicating the key is no longer present.
Alarm and Intrusionlink
The Model 3 features an alarm system and intrusion sensors (intrusion Europe market only). The alarm functionality can be disabled by the customer if they do not wish to use the feature, providing the alarm is not armed at the time. The alarm will arm when the vehicle turns off and is locked, either passively by Walk Away Lock or actively via an authenticated device (Phone Key or NFC Key Card). The alarm becomes fully armed 1 minute after the vehicle becomes secured. The alarm will become disarmed when the vehicle is unlocked or enters Drive mode. The alarm will trigger when armed and any door, frunk, or trunk open, except when commanded to open via an authenticated device. While the alarm is active, the horn will sound once per second and the turn signals will flash repeatedly.
For vehicles equipped with intrusion sensors, the alarm will trigger if the vehicle is moved or tilted, or if the windows are broken. The intrusion sensor and siren have a dedicated backup power supply.
Door Locking and Unlockinglink
When the vehicle receives an RKE lock or unlock request, the hazard lights will flash along with an audible indication. A mislock will occur if any cabin closure (doors or trunk) is detected to be open at the time of the lock request.
- Lock: One flash and audible indication
- Unlock: Double flash and double audible indication
- Mislock (failure to lock): Triple flash and triple audible indication
Locking Features:
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The Walk Away Lock feature will lock the vehicle if:
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The vehicle is not in Accessory or Drive Mode.
- The mobile device has not been detected inside the vehicle for 7 seconds.
- All doors and trunks are closed.
Note
If Phone Key is not connected to any antenna for at least 5 minutes, the vehicle will lock immediately after the device disconnects.
- Drive Away Lock will lock the vehicle if the vehicle speed exceeds 5 mph. Passive Entry features will be disabled.
- The center display lock icon can be pressed to lock all closures. Passive Entry features will be disabled.
- If Child lock is enabled, the rear doors will not unlock from an interior open request.
Unlocking Features:
- If Unlock on Park is enabled, the vehicle will unlock all closures when the vehicle shifts to Park or if the Park button is pressed while in Park.
- Passive unlock is always active, and will unlock the vehicle when a handle is pulled, as long as the Phone Key is present and authenticated.
- If the vehicle is locked, an open request from inside the vehicle will be honored, with the exception of the Child lock feature. However, the closure will remain locked and will not be able to be opened from the exterior.
Crash Scenarioslink
- If a crash is detected by the vehicle, all doors and trunks will immediately unlocked and the hazard lights will turn on.
- If a crash is detected, the exterior door handles will be disabled until 10 seconds after the event to prevent unintentional latch opening.
- If a crash is detected, the Walk Away Lock and Drive Away Lock features will be disabled.
- If a crash is detected, the glove box latch will release after a short duration.