Freelander System Description and Operation
SECURITY
86-5-6
DESCRIPTION AND OPERATION
Latch Motor Protection
To protect the door lock latches from damage, the CCU will only allow eight changes of state of the locks in any sixteen
second period or less. If eight changes of state occurs within the sixteen second period, the CCU will prevent further
operation of the latch motors for a further sixteen second period. The CCU will always prevent further operation only
when the latch motors are in an unlocked condition. If SPE is operational, the CCU will override the SPE function and
all doors will unlock if eight operations is exceeded in the sixteen second period.
The alarm system will continue to operate during the latch motor protection period.
Alarm System
The alarm system can be armed and disarmed using the vehicle key or the remote handset. The alarm system
monitors the driver's door, passenger door(s), tail door, bonnet and roof (3 door models only) using perimetric sensing.
It also monitors movement within the passenger compartment using volumetric sensing.
In certain countries, the alarm system is programmed not to arm under any circumstances.
NOTE: Hazard warning light confirmation of alarm arm or disarm is market programmable and therefore may not be
operative on certain market variants.
Perimetric Sensing
Perimetric sensing is invoked by the CCU to monitor entry to the vehicle after the alarm has been set. The panel open
switches on the driver's door, passenger door(s), tail door, bonnet and roof (3 door only) are all monitored by the CCU.
If a panel is opened after the alarm has been set, the alarm will be triggered. The horn or BBUS will sound and the
hazard warning lights will operate. On 3 door models, if the roof is off when the alarm is armed, further operation of
the roof off switch will not trigger the alarm.
Volumetric Sensing
The volumetric sensor is located in a central position on the roof panel, behind the headlining. The volumetric sensor
is a microwave sensor which monitors movement inside the vehicle to detect any possible intrusion. The vehicle can
be armed with the volumetric sensor disabled to avoid accidental triggering of the alarm if a pet is in the vehicle for
instance. The volumetric sensor is also inoperative if the CCU senses that a panel has been left open, with the
exception of the bonnet.
A fifteen second delay is initiated after arming of the alarm before signals from the volumetric sensor are interpreted
as an intrusion. This precaution is included in the CCU software to avoid accidental or nuisance triggering of the alarm.
If the alarm has been triggered, the CCU will ignore further volumetric sensor signals for the duration of the alarm
sounding. The CCU will delay volumetric sensing for a further 15 seconds after the alarm has stopped sounding,
unless ten triggers have been sensed by the volumetric sensor since the alarm was last armed.
The volumetric gain setting is controlled by the VIN stored in the CCU. The VIN informs the CCU of the vehicle body
and roof type to avoid under or over sensitivity.
If battery supply voltage falls to below 9 Volts, the CCU will ignore inputs from the volumetric sensor.
Alarm - Key Operation
Arming and disarming using the vehicle key in the driver's door key barrel will be ignored if the CCU senses that the
ignition is 'on'. In certain markets the alarm system is programmed not to arm under any circumstances, in these cases
key operation will only operate the door locking facility as described in Key Locking/Unlocking.
NOTE: Using the vehicle key in the driver door key barrel will not enable volumetric sensing.