Freelander System Description and Operation
DRIVING AIDS
DESCRIPTION AND OPERATION
86-2-7
PDC Sounder
The PDC sounder is controlled by the PDC ECU and emits a series of tones of varying frequency to inform the driver
of the distance between the vehicle and a detected object.
The PDC sounder is located in the RH side of the rear luggage compartment. A bracket is attached to the 'E' post,
behind the trim panel and provides for the attachment of the PDC sounder and the PDC ECU. The sounder is
connected to the PDC ECU via a harness connector.
PDC System Operation
When the ignition switch is in position II and reverse gear is selected, the PDC sensors are automatically activated.
The PDC ECU only activates the system if reverse is selected for more than 1 second. This avoids nuisance audible
warnings when the gear selector lever is being moved between Drive and Park.
When the system is activated, the PDC ECU illuminates the indicator LED in the PDC switch, switches on the
ultrasonic sensors and generates a single chime on the PDC sounder to indicate the system is active. If an object is
range of the sensors when the system is activated, a series of audible warnings are emitted by the PDC sounder
immediately.
If PDC operation is not required, it can be suspended temporarily by pressing the PDC switch. When reverse is
deselected and subsequently reselected, PDC will automatically become active again.
A second press of the switch is required to turn off the PDC or the PDC will be deactivated if reverse is selected and
then deselected.
Sensor Operation
The PDC ECU processes the distance readings from the ultrasonic sensors to determine if there are any objects
within the detection areas. If there are no objects in the detection areas, there are no further audible warnings. If an
object is detected, repeated audible warnings are produced on the PDC sounder.
The maximum detection range is 2000 mm (78.7 in). When an object is detected, the time delay between the audible
warning tones decreases as the distance between the detected object and the vehicle decreases until, at
approximately 370 mm (14.5 in), the audible warning tone is continuous.
After the initial detection of an object, if there is no decrease in the distance between an object and the central sensors,
the time delay between the audible warnings remains constant. If an object is detected by one of the corner sensors
only, the audible warnings stop after about 5 seconds if there is no change in the distance between the object and the
corner sensor.