Description

Parking Aid

NOTE:
A = Hardwired; N = Medium speed CAN (controller area network) bus; D = High speed CAN (controller area network) bus; P = Fiber Optic MOST









PRINCIPLES OF OPERATION
When the parking aid module activates the system, the switch LED (light emitting diode) is illuminated to indicate that the system is operating. The parking aid module then processes signals received from the sensors to determine if there is an object with the detection range of the sensors.
In the combined mode, the sensors emit a series of ultrasonic impulses and then switch to receiver mode to receive the echo reflected by an obstacle within the detection range. The received echo signals are amplified and converted from an analogue signal to a digital signal by the sensor. The digital signal is passed to the parking aid module and compared with pre-programmed data stored in an EPROM (erasable programmable read only memory) within the module. The module receives this data via the signal line from the sensor and calculates the distance from the object using the elapsed time between the transmitted and received impulse. The duration of the impulse duration is determined by the module, with the sensor controlling the frequency of the impulse output.
In receiver mode, the sensor receives impulses that were emitted by adjacent sensors. The module uses this information to precisely determine the position and distance of the object.
If no objects are detected there are no further warning tones. If an object is detected, repeated audible tones are emitted from either the front or rear audio speakers as appropriate. The time delay between the tones decreases as the distance between the object and the vehicle decreases, until at approximately 300 mm (12 inches), the audible tone becomes continuous.
If, after the initial detection of an object, there is no decrease in distance between the object and the vehicle, the audible warning tones remain constant if the object is detected by a central sensor or stops after 3 seconds if the object is detected by a corner sensor.
The audible tones will stop if the vehicle is moved out of reverse gear. The module continues to monitor the distance and will resume the warning tones if a decrease in distance is detected.
System operation is cancelled when the parking aid switch is pressed or the ignition is switched off.
All vehicles are fitted as standard with rear parking aid sensors. Higher specification vehicles may also be fitted with front parking aid sensors.
New to Range Rover is the option of a 'Park Assist' feature. This technology assists the driver to parallel park their vehicle into tight parking spaces. Once the system has identified a parking space using its ultrasonic sensors, it automatically steers the vehicle into place while the driver operates the accelerator, brake and clutch. Informative graphics and messages are displayed in the instrument cluster message center, to guide the driver through each stage of the maneuver.
A parking aid camera option supplements the information provided by the parking aid system by providing the driver with a visual display of the area directly behind the vehicle.
The following parking aid system options are available:
- Rear parking aid - standard on all vehicles
- Rear parking aid and front parking aid
- Rear parking aid and rear camera
- Rear parking aid, front parking aid and rear camera
- Rear parking aid, front parking aid, park assist and rear camera
A parking aid switch allows the driver to de-activate the parking aid system if operation is not required.
Vehicles with park assist have a separate switch to activate the system.
Park assist solely uses ultrasound sensors:
- Four sensors in the front bumper (park aid sensors)
- Four sensors in the rear bumper (park aid sensors)
- Two further sensors positioned on either side of the front of the vehicle in order to detect the available space.
The park assist system is active when the following input conditions exist:
- The park assist switch is activated. The switch is illuminated by a red LED (light emitting diode), powered by the PDC (park distance control) module. The switch is hardwired to the module
- The vehicle is travelling forwards below 18 mph (30 km/h). Vehicle speed information is sourced from directional wheel speed sensors via HS CAN (controller area network) communication from the ABS (anti-lock brake system) module to the PDC module.
The park assist sensors are hardwired to the PDC module. Scanned information is constantly transmitted to the module.
Once a parking space has been identified the PDC module calculates the parking trajectory, communicating output information to the following vehicle systems:
- The EPAS (electric power assisted steering) module via HS CAN (controller area network). The trajectory calculations are processed by the EPAS module ready for the first stage of the parking maneuver. Once a vehicle speed signal is received (vehicle reversing) the EPAS module independently controls the steering trajectory.
- The instrument cluster message center via HS CAN (controller area network). The message center displays the relevant park assist information to the driver
- The CJB (central junction box) via HS CAN (controller area network) which 'gateway's' front and rear park aid sensor information to the Touch-screen via MS CAN (controller area network). The Touchscreen 'gateway's' the sensor information to the AAM (audio amplifier module) via the MOST ring. The audible beep warnings are broadcast on the relevant system speakers.

Service Information
If the self check system fails the following warnings apply:
- The instrument cluster displays an error message
- The front speakers emit a 3 second continuous tone
- A DTC (diagnostic trouble code) is logged in the PDC module.
If a sensor failure is detected:
- The front speakers emit a 3 second continuous tone
- HLDF screen has a message to consult dealer
- A DTC (diagnostic trouble code) is logged in the PDC module.

Distance Calculation

NOTE:
A = Intermittent warning tone; B = Continuous warning tone





The maximum detection range for the front sensors is 800 mm (31 inches) for the central sensors and 600 mm (23.5 inches) for the corner sensors.
The maximum detection range for the rear sensors is 1500 mm (60 inches) for the central sensors and 600 mm (23.5 inches).

Searching for a Parking Space
Once the driver has identified a possible parking space the park assist system carries out the following checks and procedures:
- The system constantly searches for a space on the passenger side of the vehicle. Space on the driver's side is searched via instruction from direction indicator operation.
- As the vehicle moves forward, parallel to a row of parked vehicles, it detects the parked vehicles.
- The system can detect a space up to four meters away from the side of vehicle. The system will only select a space which is 1.2 times the length of the vehicle (or greater) and deep enough to park the vehicle.
- If the driver chooses to park in the detected space, the vehicle is stopped and reverse gear selected.
- The system calculates the appropriate trajectory to park the vehicle into the detected space.

NOTE:
If the driver is in slow moving traffic the system will be activated frequently when passing by other vehicles.









Reversing into Space
When reverse gear is selected the instrument cluster message center displays the appropriate parking instructions.
The following checks and procedures are applied:
- The driver follows message center instructions, gently applying the accelerator, moving the vehicle backwards along the trajectory calculated by the park assist system
- Detected obstacles at 1.5m generate an intermittent sound tone over the vehicle rear speakers
- Detected obstacles at 1.0m generate a semi continuous sound tone over the vehicle rear speakers
- Detected obstacles at 0.3m generate a constant sound tone over the vehicle rear speakers
- On reaching the end of the reversing maneuver the driver is instructed to apply the footbrake to stop the vehicle
- The driver selects a forward gear to prepare for the next stage of the parking maneuver
- If the vehicle has been parked in a large space the maneuver is complete and the system operation ends.

Driver selects reverse - reversing maneuver begins





Driving Forward within Space
If the vehicle is not in the correct position after the initial reversing maneuver, the driver is instructed to select a forward gear; 'Drive' (automatic transmission) or 1st gear (manual transmission).
When the forward gear is selected, the instrument cluster message center displays the appropriate parking instructions.
The following checks and procedures are applied:
- The driver follows message center instructions, gently applying the accelerator, moving the vehicle forwards along the trajectory calculated by the park assist system
- Detected obstacles at 0.8 m generate an intermittent sound tone over the vehicle front speakers
- Detected obstacles at 0.6m generate a semi continuous sound tone over the vehicle front speakers
- Detected obstacles at 0.3m generate a constant sound tone over the vehicle front speakers
- On reaching the end of the forward maneuver the driver is instructed to apply the footbrake to stop the vehicle
- The driver selects reverse gear to prepare for the next stage of the parking maneuver
- If the vehicle is in the final position the maneuver is complete and the system operation ends.

Driver selects forward gear - forward moving maneuver begins





If the vehicle is parking in a smaller space more shuffling may be required to complete the parking maneuver.

Driver selects reverse gear - further reversing is completed





Completion of Parking
Once the system has detected the vehicle is parked in the final position the message center informs the driver the park assist function is complete. The driver selects neutral/park gear position and switches off the engine.
The park assist system is configured to operate a maximum of five maneuvers, with each movement counting as one maneuver. This is more than adequate as most park assist maneuvers are complete and the vehicle is in the final parking position within three reverse and forward movements.

Parking Aid Module
The parking aid module is located on the LH (left-hand) side of the luggage compartment, behind the 'C' pillar trim panel.
The parking aid module has three connectors which provide for power, ground and CAN (controller area network) bus connections, front parking aid sensors and rear parking aid sensors.
The high speed CAN (controller area network) bus connections provide for the receipt of the following information from other systems:
- ABS (anti-lock brake system) module - Road speed signal
- TCM (transmission control module) - Reverse gear engaged signal
- Instrument cluster - Ambient temperature signal.
The module also outputs messages on the medium speed CAN (controller area network) bus which are received by the Integrated Control Panel (ICP). The ICP processes these messages and converts them into medium speed CAN (controller area network) messages which are passed to the integrated audio module that converts them into Media Orientated System Transport (MOST) signals system. These signals are then used by the power amplifier to emit the applicable warning tones from the front or rear audio speakers when an object is detected by the front or rear parking aid sensors. A warning tone can also be emitted to alert the driver to a fault in the parking aid system.
The parking aid module performs self check routines and when the system is active checks the sensor wiring for short or open circuits. If a fault is detected a code is stored in a memory in the module and if necessary either the front and/or rear sensors can be disabled. The driver is made aware of any fault condition by the parking aid switch LED (light emitting diode) flashing and a continuous warning tone being emitted for 3 seconds, in place of the normal short tones when the system is functioning normally. Fault codes can be read using the IDS (Integrated Diagnostic System) via the diagnostic socket.

Parking Aid Switch









The parking aid switch is located in the instrument panel switch pack, above the touch screen. The switch is the LH (left-hand) switch with an integral LED (light emitting diode).
The switch is a non-latching push switch which allows the driver to select the parking aid system on or off. When pressed, the switch momentarily connects a ground to the parking aid module. The LED (light emitting diode) indicates when the parking aid system is active. The LED (light emitting diode) is controlled by the parking aid module.
The switch allows the driver to disable the parking aid system when reverse gear is selected or to activate the parking sensors when not in reverse gear.
If a fault exists in the parking aid system, the LED (light emitting diode) flashes continuously when reverse gear is selected or the driver selects the parking sensors on, using the switch.

Park Assist Switch