Anti-Theft - Active
Anti-Theft - Active
COMPONENT LOCATIONS
NOTE:
RHD (right-hand drive) installation shown, LHD (left-hand drive) installation similar.
GENERAL
The active anti-theft system monitors the hinged panels for unauthorized opening. On some vehicles, the active anti-theft system also incorporates interior monitoring and vehicle tilt sensing functions. If an alarm event is detected, the active anti-theft system generates audible and visual alarm signals. The active anti-theft system is controlled by the CJB (central junction box) and is configured to automatically arm and disarm with operation of the CLS (central locking system). For additional information, refer to Handles, Locks, Latches and Entry Systems Description and Operation
The active anti-theft system incorporates:
- An alarm indicator.
- A BBUS (if fitted).
- A volumetric sensor (if fitted).
- A tilt sensor (if fitted).
The active anti-theft system also uses:
- The CJB (central junction box).
- The hood, door and tailgate ajar switches. For additional information, refer to Handles, Locks, Latches and Entry Systems Description and Operation
ALARM INDICATOR
The alarm indicator is installed in the instrument cluster to provide a visual indication of the active anti-theft system status. Operation of the alarm indicator is controlled by a hardwired input from the CJB (central junction box), which pulls the input to ground to illuminate the alarm indicator.
The alarm LED will begin to flash once every 2 seconds to indicate that the vehicle alarm is armed.
BBUS
The BBUS is installed in the engine compartment on the RH (right-hand)side of the bulk head. Depending on the CJB (central junction box) configuration, the BBUS can be used to produce the audio acknowledgment for arming and disarming of the active anti-theft system as well as the audio warning after an alarm has been triggered.
The BBUS is normally operated by a permanent battery feed from the CJB (central junction box). An integral 7.2 V rechargeable battery powers the BBUS if it is disconnected from the vehicle battery.
The BBUS sounds when it receives an alarm or acknowledgment signal from the CJB (central junction box). While the active anti-theft system is armed, the BBUS also monitors the battery power supply and the arm/disarm signal line from the CJB (central junction box), and operates the sounder if the battery power supply or the arm/disarm signal line is disconnected. The CJB (central junction box) arms and disarms the BBUS together with the rest of the active anti-theft system.
Once an alarm has been triggered, the BBUS cycles the sounder on for 30 seconds and off for 10 seconds, for 5 minutes or until it receives a disarm signal from the CJB (central junction box). If the alarm trigger is still present, the 5 minutes of on/off cycles is repeated a further 2 times.
VOLUMETRIC SENSOR (IF FITTED)
The volumetric sensor is installed behind openings in the rear interior lamp and monitors for intrusion into the passenger compartment when the alarm is armed.
The volumetric sensor consists of a microcontroller, two acoustic transmitters one acoustic receiver. One transmitter pair and a receiver face forwards and one transmitter faces rearwards to ensure complete coverage of the passenger compartment. The front transmitter pair and receiver are in a rubber mounting attached to the microcontroller housing. The rear transmitter is in a remote rubber mounting and connected to the microcontroller housing by a two wire lead.
The volumetric sensor is powered by a permanent battery feed from the CJB (central junction box). The CJB (central junction box) activates and de-activates the volumetric sensor when it arms and disarms the active anti-theft system. When the volumetric sensor is active it outputs ultrasonic pulses from the transmitters and checks the echoes picked up by the receivers for changes to the passenger compartment profile. If it detects a change of profile indicating movement in the passenger compartment the volumetric sensor reports the alarm to the CJB (central junction box).
Each time the volumetric sensor is activated it performs a self test. If there are no faults the volumetric sensor sends an acknowledgment signal to the CJB (central junction box). If the CJB (central junction box) does not receive the acknowledgment signal it de-activates the volumetric sensor.
TILT SENSOR (IF FITTED)
The tilt sensor monitors for changes of vehicle attitude while the alarm is armed. The tilt sensor is installed within the BBUS sounder and is located in the engine compartment on the RH (right-hand)side of the bulk head.
The tilt sensor incorporates a two axis sensor controlled by a microprocessor. A permanent battery feed from the CJB (central junction box) powers the tilt sensor. The CJB (central junction box) activates and de-activates the tilt sensor when it arms and disarms the active anti-theft system.
The tilt sensor measures the longitudinal and transverse angles of the vehicle over a range of ±16 degrees from the horizontal. When the tilt sensor is activated, it stores the current angles in memory. If the vehicle changes attitude in either direction by more than the limit the tilt sensor sends an alarm signal to the CJB (central junction box), which triggers the BBUS.
NOTE:
If the security systems detects a fault with the tilt sensor it will indicate this by emitting 2 error tones from the alarm siren when the vehicle is unlocked and disarmed.
Each time the tilt sensor is activated it performs a self test. If there are no faults the tilt sensor sends an acknowledgment signal to the CJB (central junction box). If the CJB (central junction box) does not receive the acknowledgment signal it de-activates the tilt sensor.
SYSTEM OPERATION
The active anti-theft system arms and disarms in conjunction with the locking and unlocking of the central locking system. Depending on the configuration of the CJB (central junction box), the active anti-theft system can be armed and disarmed when the locking system is activated with the smart key. Visual and audible confirmation of the active anti-theft system arming and disarming, using the direction indicators and the BBUS, are also configurable in the CJB (central junction box).
When the vehicle is superlocked, the CJB (central junction box) sends an arming signal to the tilt sensor, the BBUS and the volumetric sensor. If the CJB (central junction box) does not receive an acknowledgment signal from the tilt sensor and the volumetric sensor within 1 second, the CJB (central junction box) disables the associated alarm feature for the remainder of the armed cycle.
To set alarm sensors override/partial alarm protection, select alarm sensors to off on the vehicle instrument cluster menu and then press the lock button twice within three seconds. The hazard warning lights will flash twice to confirm the locking state and an audible arm chirp will sound to confirm the vehicle is double locked. The alarm LED in the vehicle instrument cluster will begin to flash once every 2 seconds to confirm the alarm state. This feature prevents accidental triggering of the active anti-theft system during transportation of the vehicle or if a pet is left in the vehicle.
Volumetric Sensing
The CJB (central junction box) begins volumetric sensing 30 seconds after the alarm being armed and the vehicle is double locked.
If the alarm has been triggered, the CJB (central junction box) will ignore further volumetric sensor signals for the duration of the alarm. The CJB (central junction box) resumes volumetric sensing 30 seconds after the alarm has stopped sounding.
Volumetric sensing and tilt sensing are disabled if the CJB (central junction box) receives a tail door open signal from the smart key. The CJB (central junction box) resumes volumetric sensing and tilt sensing 30 seconds after the upper tail door closes again.
NOTE:
If the security systems detects a fault with the volumetric sensor it will indicate this by emitting 2 error tones from the alarm siren when the vehicle is unlocked and disarmed.
Emergency Disarming
If the alarm has been triggered and cannot be disarmed with the smart key, it can be disarmed with the ignition switch as follows:
- Unlock the left-hand front door using the emergency key blade.
- Authenticate the Land Rover smart key by holding the smart key adjacent/over the immobilizer antenna unit, located on the central fascia.
- Press the Start/Stop button to authenticate the Land Rover smart key.
- The alarm will be disarmed.
NOTE:
When the left-hand front door is unlocked and opened using the emergency key, the alarm will sound until the Land Rover Smart Key is authenticated.
Deactivating the alarm when triggered
If the alarm has been triggered, it can be deactivated by any one of the following methods
Pressing the unlock button on the Land Rover smart key.
- Pressing the START/STOP button with a valid Land Rover smart key present.
- Authenticating the Land Rover smart key via the immobilizer antenna unit.
CONTROL DIAGRAM
NOTE:
A = Hardwired connection; O = LIN bus
