Description
Anti-Theft - Passive
NOTE:
A = Hardwired; D = High speed CAN; N = Medium speed CAN; O = LIN bus
Passive Entry
Passive Starting
Passive Start System
Upon receiving the 'start button pressed' hardwired signal, the CJB (central junction box) sends a message via the medium speed CAN (controller area network) bus to the KVM initiating the vehicle starting process.
The KVM then energizes the low frequency antennas within the vehicle cabin which transmit a 125KHz signal to the Jaguar Smart Key, upon receipt of the LF signal the Jaguar Smart Key transmits either a 433 MHz or a 315 MHz RF signal containing the authorization code to the RF receiver.
The RF receiver relays the code, via a serial communication line, to the KVM which then checks and approves the code as valid. The KVM will only respond to a valid Jaguar Smart Key.
The KVM continues the passive start process by communicating a 'Jaguar Smart Key valid' signal to the CJB (central junction box) via the medium speed CAN (controller area network) bus, Once the CJB (central junction box) receives the Jaguar Smart Key authorization it confirms the response matches with an internal calculation.
Before the CJB (central junction box) sends a mobilization signal to the ECM (engine control module), via the high speed CAN (controller area network) bus, it will exchange encrypted data with following components:
- The instrument cluster via the high speed CAN (controller area network) bus,
- The steering column lock via the high speed CAN (controller area network) bus, to authorize unlocking the steering column. The steering column unlocking function is powered by the CJB (central junction box) and grounded via the instrument cluster
When the CJB (central junction box) receives a hardwired Park/Neutral signal from the JaguarDrive Selector, a high speed CAN (controller area network)bus message from the ABS (anti-lock brake system) module and a simultaneous start/stop switch signal it interprets this as an engine crank request. Before the engine crank request is processed, the CJB (central junction box) verifies the brake pressure signal received from the ABS (anti-lock brake system) module. If the signal is greater than the stored threshold value, a crank request signal is sent to the ECM (engine control module) on the high speed CAN bus.
NOTE:
If the KVM fails to locate the Smart Key, a message 'SMART KEY NOT FOUND REFER TO HANDBOOK' will appear in the instrument cluster message center and the keyless start back-up process will have to be used to mobilize and start the vehicle.
Keyless Start Back-up
If the vehicle has been unlocked using the emergency key blade or the Smart Key is not detected by the vehicle, it will be necessary to use the keyless start back-up system to disarm the alarm and start the engine. The following process must be followed in this event:
- Position the Smart Key against the underside of the instrument panel, on the outboard side of the steering column, with the buttons facing downwards. This is the location of the IAU.
- Holding the Smart Key in position and with the brake pedal depressed, press the start/stop button to start the engine.
This process bypasses the data exchange between the KVM and the CJB (central junction box). A transponder within the Smart Key is detected by the IAU. The IAU confirms the code output from the transponder and communicates this code confirmation with the CJB (central junction box) via a LIN (local interconnect network) bus connection. The CJB (central junction box) then initiates the vehicle start process in the normal manner.
Immobilizer Antenna Unit (IAU)
The IAU is located on the driver's side behind the instrument panel just below the auxiliary lighting switch. The IAU cannot be seen as it is located behind the trim panel. The IAU is used if the KVM is unable to authorize the Smart Key. The driver will be alerted to this by a chime and a message in the instrument cluster message center 'SMART KEY NOT FOUND REFER TO HANDBOOK'.
If the KVM is unable to identify the Smart Key, for example if the Smart Key battery voltage is low or there is local RF interference, the transponder within the Smart Key can be read by holding the smart key against then instrument panel.
Low Frequency Antenna
Five Low Frequency (LF) antennae for the passive start system are positioned in specific locations within the vehicle.
The KVM transmits an LF signal via the antennas which is received by the Smart Key. The Smart Key then responds by transmitting a RF signal which is received by the RF receiver and passed to the KVM for authorization.
Keyless Vehicle Module
The keyless vehicle module controls signal transmissions to and from the Smart Key and provides authorization to allow the vehicle to be started. The module has a medium speed CAN connection to the CJB for authorizing vehicle starting.
Radio Frequency Receiver
The Radio Frequency (RF) receiver transmission is received from the Smart Key to enable key identification.