Wheels and Tires - Wheels and Tires - Overview
Description and Operation
OVERVIEW Published: 25-May-2012
A number of alloy wheel designs are available ranging from 17 to 20 inch in diameter. A Tire Pressure Monitoring System
(TPMS) is used to monitor the air pressure in each tire and inform the driver if the pressure falls below predetermined
thresholds.
All wheels are of cast construction in aluminum alloy with the choice of wheel design dependant on the vehicle trim level and
engine derivative.
On normally aspirated petrol models and all diesel models a 4J X 18 inch temporary spare wheel is supplied as standard,
supercharged petrol models are supplied with a 4Jx19 inch temporary spare wheel. In some major European markets an Instant
Mobility System is offered as an alternative to the spare wheel. The Instant Mobility System is capable of providing a
temporary repair and tire inflation to a puncture of up to 6mm in diameter in the tread area of the tire. A puncture in the tire
wall cannot be repaired using the system.
The vehicle jack and accessories are stored in the spare wheel-well in the luggage compartment.
Tire Changing
WARNINGS:
Tires must be inflated to the recommended pressures when the tires are cold (ambient temperature) only. Refer to label
on the 'B' pillar for recommended tire pressures. If the tires have been subjected to use or exposed to direct sunlight, move
the vehicle into a shaded position and allow the tires to cool before checking or adjusting the pressures.
Valve stem seal, washer nut, valve core and cap should be replaced at every tire change. Valve stem seal, washer and
nut must be replaced if the valve retention nut is loosened. Sensor units and nuts must be fitted using correct torque figures
and associated profile. Damage to the vehicle and consequently injury to the vehicle's occupants may result if these
instructions are not adhered to.
NOTE: The TPMS valve should be serviced using the suitable service kit, each time the tyre is dismounted, to ensure an
air tight seal. Attention should be made to the detail of fitting this kit.
Vehicles fitted with TPMS can be visually identified by an external metal locknut and valve of the tire pressure sensor on the
road wheels. Vehicles without TPMS will have rubber tire valve.
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7 Initiators 8 TPMS module 9 Instrument cluster
Tire Pressure Monitoring System (TPMS) System Operation
The controlling software for the Tire Pressure Monitoring System (TPMS) is located within a Tire Pressure Monitoring System
Module. The software detects the following:
When the tire pressure is below the recommended low pressure value - under inflated tire.
The location of the tire on the vehicle that is below the recommended pressure.
Malfunction warning.
The TPMS system comprises:
Tire pressure monitoring system module located below the right-hand front seat.
Tire pressure receiver located near the gear shifter within the floor console.
Two front initiators positioned forward of the wheels and behind the fender splash shields.
Two rear initiators positioned rearward of the wheels and assembled on dedicated brackets located behind the fender
splash shields.
Four sensors, each sensor is integral with a tire valve and located within the tire; the space saver spare wheel is not
fitted with a sensor.
The four initiators are hard wired to the TPMS module. The initiators transmit 125 KHz Low Frequency (LF) signals to the tire
pressure sensors which respond by modifying the mode status within the Radio Frequency (RF) transmission. The 315 or 433
MHz RF signals are detected by the tire pressure receiver which is connected directly to the TPMS module. The received RF
signals from the tire pressure sensors are passed to the TPMS module and contain identification, pressure, temperature and
acceleration information for each wheel and tire.
The TPMS module communicates with the instrument cluster via the medium speed CAN bus to provide the driver with
appropriate warnings. The TPMS module also indicates status or failure of the TPMS or components.
Tire Location and Identification
The TPMS can identify the position of the wheels on the vehicle and assign a received tire pressure sensor identification to a
specific position on the vehicle, for example front left, front right, rear left and rear right. This feature is required because of
the different pressure targets and threshold that could exist between the front and rear tires.
The wheel location is performed automatically by the TPMS module using an 'auto-location' function. This function is fully
automatic and requires no input from the driver. The TPMS module automatically re-learns the position of the wheels on the
vehicle if the tire pressure sensors are replaced or the wheel positions on the vehicle are changed.
The TPMS software can automatically detect, under all operating conditions, the following:
one or more new tire pressure sensors have been fitted
one or more tire pressure sensors have stopped transmitting
TPMS module can reject identifications from tire pressure sensors which do not belong to the vehicle
two 'running' wheels on the vehicle have changed positions.
If a new tire pressure sensor is fitted on any 'running' wheel, the module can learn the new sensor identification automatically
through the tire learn and location process.
The tire-learn and location process is ready to commence when the vehicle has been stationary or traveling at less than 12
mph (20 km/h) for 15 minutes. This is known as 'parking mode'. The learn/locate process requires the vehicle to be driven at
speeds of more than 12 mph (20 km/h) for 15 minutes. If the vehicle speed reduces to below 12 mph (20 km/h), the learn
process timer is suspended until the vehicle speed increases to more than 12 mph (20 km/h), after which time the timer is
resumed. If the vehicle speed remains below 12 mph (20 km/h) for more than 15 minutes, the timer is set to zero and process
starts again.
Low Pressure Monitoring
The tire low pressure sensor transmits by RF (315 MHz or 433 MHz depending on market) signal. These signals contain data
which corresponds to tire low pressure sensor identification, tire pressure, tire temperature, acceleration and tire low pressure
sensor mode.
Each time the vehicle is driven, the tire pressure monitoring system module activates each LF antenna in turn. The
corresponding tire low pressure sensor detects the LF signal and responds by modifying the mode status within the RF
transmission.
The system enters 'parking mode' after the vehicle speed has been less than 20 km/h (12.5 miles/h) for 12 minutes. In parking
mode the tire low pressure sensors transmit a coded signal to the tire pressure monitoring system module once every 13
hours. If the tire pressure decreases by more than 0.06 bar (1 lbf/in²) the tire low pressure sensor will transmit more often as
pressure is lost.
As each wheel responds to the LF signal from the tire pressure monitoring system module, it is assigned a position on the
vehicle and is monitored for the remainder of that drive cycle in that position.
DTC Description Possible Cause Action U0142-00
Lost Communication With
Body Control Module "B"
-no sub type information
CAN bus fault
Auxiliary Junction Box fault Refer to the electrical wiring diagrams and check
Auxiliary Junction Box power and ground supplies for
short, open circuit. Carry out CAN network integrity
tests. U0155-00
Lost Communications With
Instrument Panel Cluster
(IPC) Control Module-no
sub type information
CAN bus fault
Instrument cluster fault Refer to the electrical wiring diagrams and check
instrument cluster power and ground supplies for
short, open circuit. Carry out CAN network integrity
tests. U0164-00
Lost Communication With
HVAC Control Module-no
sub type information
CAN bus fault
Climate control module
fault Refer to the electrical wiring diagrams and check
climate control module power and ground supplies for
short, open circuit. Carry out CAN network integrity
tests. U0300-00
Internal Control Module
Software Incompatibility-no
sub type information
Incompatible tire pressure
monitoring system module
for vehicle CAN network Check correct tire pressure monitoring system module
is installed to vehicle specification, otherwise
suspect the Auxiliary Junction Box. U0415-00
Invalid Data Received From
Anti-Lock Brake System
(ABS) Control Module-no
subtype information
Invalid data received from
the Anti-Lock Braking
System Control Module
CAN bus fault
Anti-Lock Braking System
fault Check Anti-Lock Braking System control module and
Instrument Cluster for related DTCs and refer to the
relevant DTC Index. Carry out CAN network integrity
tests. U0424-00
Invalid Data Received From
HVAC Control Module-no
sub type information
HVAC control module fault Check climate control module for related DTCs and
refer to relevant DTC Index. U1A14-49
CAN Initialisation Failure-
internal electronic failure
Tire pressure monitoring
system module fault Install a new tire pressure monitoring module. Refer
to the new module/component installation note at
the top of the DTC Index. U3000-55
Control Module-not
configured
Tire pressure monitoring
system configuration data
is invalid Check and amend the car configuration file. U3000-87
Control Module-missing
message
Tire pressure monitoring
system configuration data
not received Check the Auxiliary Junction Box for related DTCs and
refer to the relevant DTC Index. Carry out CAN
network integrity test. U3002-81
Vehicle Identification
Number - invalid serial data
received
Tire pressure monitoring
system module and vehicle
VIN mis-match
NOTE: This DTC indicates that the tire pressure
monitoring system module is not the original part
installed to the vehicle at the factory/dealer and
could have been substituted. Refer to the note above
the DTC index about replacing components which may
remain under manufacturer warranty.
Re-install the original or a new tire pressure monitoring system control module.
Component Tests
Wheels and Tires
For wheel and tire specification information (pressures, torques, etc).
When replacing wheels or tires, local legislation regarding health and safety must be complied with.
If the vehicle has a Tire Pressure Monitoring System installed, only Jaguar approved wheels and tires should be used. If the
wheel and tire size is changed (for example from R18 to R20) the Tire Pressure Monitoring System module should be updated
with the correct pressure information appropriate to the new wheel and tire set. Update the Tire Pressure Monitoring System
module using the Jaguar approved diagnostic system.
As a general guideline, only replace tires in pairs or as a set, and only with tires of equivalent size and specification.
Confirm the symptoms of the customer complaint.
As much information as possible should be gathered from the driver to assist in diagnosing the cause(s).
1. Before a road test, carry out a basic inspection to make sure the vehicle is safe and legal to drive.
Basic inspection
Correct tire inflation
Legal tire tread depth
7 Rear accelerometer 8 Instrument cluster 9 JaguarDrive selector module 10 ABS (anti-lock brake system) module 11 TCM (transmission control module) 12 ECM (engine control module) 13 RH (right-hand) rear damper 14 RH front damper 15 LH (left-hand) front damper 16 LH rear damper 17 LH rear suspension height sensor 18 RH rear suspension height sensor 19 LH front suspension height sensor 20 RH front accelerometer 21 RH front suspension height sensor 22 Adaptive damping module 23 LH front accelerometer
PRINCIPLES OF OPERATION System Operation
The adaptive damping module uses a combination of information from other system modules and data from the accelerometers
and suspension height sensors to measure the vehicle and suspension states and driver inputs. Using this information, the
adaptive damping module applies algorithms to control the dampers for the current driving conditions.
The adaptive damping module receives signals on the high speed CAN bus from the following system components: Brake Pressure - ABS module. Brake Pressure Quality Factor - ABS module. Car Configuration Parameters - AJB. Center Differential Range Actual - ECM. Engine Speed - ECM. Engine Speed Quality Factor - ECM. Engine Torque Flywheel Actual - ECM. Engine Torque Flywheel Actual Quality Factor - ECM. Gear Position Target - TCM. Lateral Acceleration - ABS module. Power Mode (Ignition Signal) - CJB. Power Mode Quality Factor - CJB. Roll Stability Control Mode - ABS module. Steering Wheel Angle - ABS module. Steering Wheel Angle Speed - ABS module. Steering Wheel Angle Status - ABS module. Terrain Mode Requested - JaguarDrive selector.
Torque Converter Slip - TCM. Vehicle Information Parameters HS - AJB Vehicle Speed - ABS module. Vehicle Speed Quality Factor - ABS module. Front Left Wheel Speed - ABS module. Front Left Wheel Speed Quality Factor - ABS module. Front Right Wheel Speed - ABS module. Front Right Wheel Speed Quality Factor - ABS module. Rear Left Wheel Speed - ABS module. Rear Left Wheel Speed Quality Factor - ABS module. Rear Right Wheel Speed Quality Factor - ABS module. Rear Right Wheel Speed - ABS module. The adaptive damping module also outputs information on the high speed CAN bus for use by other systems as follows: Fault Message - instrument cluster.
Terrain Mode Change Status - JaguarDrive selector.
Terrain Mode - JaguarDrive selector.
The adaptive damping module monitors the input signals and operates the damper solenoids. The input signals are used in
control modes and a force required for each damper for that mode is calculated. An arbitration mode monitors the force
requirements from each mode and apportions a force to a damper. The force is converted to the appropriate current and sent to
the damper.
The control modes are as follows:
2 Main piston 3 Tube 4 Bypass valve (closed) 5 Piston and rod assembly ACCELEROMETERS
Three accelerometers are used in the adaptive dynamics system. The accelerometers are located as follows:
One each on the rear edge of the radiator support panel.
One in the luggage compartment, in the rear LH corner adjacent to the rear lamp assembly.
The accelerometers measure acceleration in the vertical plane and output a corresponding analogue signal to the adaptive
damping module. The algorithms in the adaptive damping module calculate the heave, pitch and roll motions of the vehicle,
which are used by the module to control road induced body modes.
Each accelerometer is connected to the adaptive damping module via three wires, which supply ground, 5 V supply and signal
return.
The sensing element comprises a single parallel plate capacitor, one plate of which moves relative to the other dependant on
the force (acceleration) applied. This causes the capacitance to change as a function of applied acceleration. This capacitance
is compared with a fixed reference capacitor in a bridge circuit and the signal is processed by means of a dedicated integrated
circuit to generate an output voltage that varies as a function of applied acceleration. The sensors output a signal voltage of
approximately 1 V/g ± 0.05 V/g.
SUSPENSION HEIGHT SENSORS
Four suspension height sensors are used in the adaptive dynamics system, two for the front suspension and two for the rear
suspension. A front suspension height sensor is attached to each side of the front subframes and connected by a sensor arm
and sensor link to the related lower lateral arm of the front suspension. A rear suspension height sensor is attached to each
side of the rear subframe and connected by a sensor arm and sensor link to the related upper control arm of the rear
suspension. On each suspension height sensor, the sensor arm and sensor link convert linear movement of the suspension into
rotary movement of the sensor shaft.
The sensors are also used for the static dynamic headlamp leveling system on vehicles fitted with xenon headlamps.
The suspension height sensors measure suspension displacement at each corner of the vehicle and output a corresponding
analogue signal to the adaptive damping module. The algorithms in the adaptive damping module calculate the position,
velocity and frequency content of the signals and use the results for wheel control.
Each suspension height sensor is connected to the adaptive damping module via three wires, which supply ground, 5 V supply
Published: 11-May-2011
Ride and Handling Optimization - Ride and Handling Optimization - System
Operation and Component Description
Description and Operation
JAGUARDRIVE CONTROL OPERATION
Engine Management System System Operation
The Engine Management System (EMS) varies the accelerator pedal maps to change the amount of torque per percentage of
pedal travel. The EMS can also change the accelerator pedal response to control the allowed torque change relative to the
speed of pedal travel.
Each driving mode uses a combination of operating parameters for each sub-system. Changing between driving modes initiates
a different set of operating characteristics, which will be noticeable to the driver. The driver will notice differences in engine
response when, for example, the accelerator pedal is held in a constant position and the driving mode is changed from Winter
to Dynamic, the driver will notice the torque and engine speed increase. Similarly, if the mode is changed from Normal or
Dynamic to Winter the driver will notice a reduction in torque and engine speed.
NOTE: The change in torque and engine speed can take approximately 30 seconds and care must be taken not to confuse
the JaguarDrive Control system operation with an EMS fault.
Transmission Control
The TCM (transmission control module) changes the shift maps for the JaguarDrive Control mode selected. This changes the
shift points providing early or late upshifts and downshifts. For example, on slippery surfaces in Winter mode the transmission
will select 2nd gear for starting from a standstill on a flat surface to minimize wheel slip.
Anti-lock Braking System Control
The ABS (anti-lock brake system) module controls several vehicle functions and adjusts the operating parameters of these
functions to optimize the selected JaguarDrive Control mode. Traction control uses different slip/acceleration thresholds to
improve traction and vehicle composure. For example, the system sensitivity is increased on slippery surfaces to reduce wheel
spin.
If TracDSC is selected or DSC is switched off, then subsequently the JaguarDrive Control mode is changed, DSC is automatically
switched back on (or to TracDSC for Dynamic mode).
The stability control uses different threshold values for the selected mode, reducing the requirement for the driver to change
the DSC system mode for optimum performance in various driving scenarios.
Incorrect Mode Usage
Selection of an inappropriate mode is discouraged in the following ways:
The active mode icon is continually displayed in the instrument cluster message center
In any special mode, when the ignition has been in the off position continuously for more than 6 hours, the JaguarDrive
Control system defaults to the special modes off (DSC on).
Selection of an inappropriate mode for the conditions will not endanger the driver or immediately cause damage to the vehicle.
Continued use of an inappropriate mode may reduce the life of some components. The driver may notice a different vehicle
response, with the engine and transmission responses being different than in the special modes off.
Driver Information
The instrument cluster contains a message center, which displays vehicle information to the driver. The message center
contains the JaguarDrive Control mode icons, which display the currently selected mode. If no symbol is displayed, no special
mode is selected and the system is in special modes off.
Any required changes to the subsystems are also passed to the driver in the form of warning illumination in the instrument
cluster or appropriate messages in the message center, DSC off for example.
In Dynamic mode when the transmission is in manual mode, the gear information is displayed in amber when the appropriate
engine speed is reached for optimum sporty change point.
DIAGNOSTICS
JaguarDrive Control relies on the correct functionality of the sub-systems. If one of the sub-systems develops a fault, the
JaguarDrive Control system will not function, even though the fault is not in the JaguarDrive Control system.
The JaguarDrive Selector module and rotary control should only be investigated if there are no apparent faults in any of the
sub-systems. If a fault in a sub-system is subsequently corrected, the JaguarDrive Control system will function normally after
an ignition on and off cycle.
BRAKE CALIPERS System Operation
When hydraulic pressure is supplied to the caliper, the pistons extend to force the inner pad against the brake disc. The caliper
reacts and slides along two guide pins to bring the outer pad into contact with the brake disc.
BRAKE PAD WEAR SENSORS
When a brake pad incorporating a brake pad wear sensor is approximately 75% worn, the sensor wire within the pad material
is worn through and the brake pad wear sensor goes open circuit. When the instrument cluster detects the open circuit, it
illuminates the amber LED (light emitting diode) in the brake warning indicator, displays an appropriate warning in the
message center and sounds a warning chime.
Refer to: Instrument Cluster (413-01 Instrument Cluster, Description and Operation).
NOTE: A new pad wear sensor lead must be fitted whenever the brake pads are changed, irrespective of the brake pad
warning sensor being triggered.
BRAKE CALIPERS Component Description
Each caliper is mounted within a fixed carrier that is secured to the front wheel knuckle with two bolts. The inboard brake pad
of the LH (left-hand) brake incorporates a wear sensor.
Each outboard brake pad is installed with a pressed steel anti-rattle spring. On SC (supercharger) vehicles, a badge with the
'R' symbol is formed on the anti-rattle spring.
BRAKE PAD WEAR SENSORS
The brake pad wear sensor is wired in series with a wear sensor on the RH (right-hand) rear brake and the instrument cluster.
If the thickness of one of the brake pads connected to a wear sensor decreases to a predetermined limit, the instrument
cluster illuminates the brake warning indicator.
BRAKE CALIPERS System Operation
When hydraulic pressure is supplied to the caliper, the pistons extend to force the inner pad against the brake disc. The caliper
reacts and slides along two guide pins to bring the outer pad into contact with the brake disc.
BRAKE PAD WEAR SENSORS
When a brake pad incorporating a brake pad wear sensor is approximately 75% worn, the sensor wire within the pad material
is worn through and the brake pad wear sensor goes open circuit. When the instrument cluster detects the open circuit, it
illuminates the amber LED (light emitting diode) in the brake warning indicator, displays an appropriate warning in the
message center and sounds a warning chime.
Refer to: Instrument Cluster (413-01 Instrument Cluster, Description and Operation).
NOTE: A new pad wear sensor lead must be fitted whenever the brake pads are changed, irrespective of the brake pad
warning sensor being triggered.
BRAKE CALIPERS Component Description
Each caliper is mounted within a fixed carrier that is secured to the rear wheel knuckle with two bolts. Each outboard brake pad
is installed with a wire anti-rattle spring.
The brake calipers on SC (supercharger) vehicles are painted and also include a logo badge, secured with two screws, which
must be removed in order to change the brake pads.
The inboard brake pad of the RH (right-hand) brake incorporates a wear sensor.
BRAKE PAD WEAR SENSORS
The brake pad wear sensor is wired in series with a wear sensor on the LH (left-hand) front brake and the instrument cluster. If
the thickness of one of the brake pads connected to a wear sensor decreases to a predetermined limit, the instrument cluster
illuminates the brake warning indicator.