wheel JAGUAR XFR 2010 1.G Workshop Manual

60 Oil seal The multi-plate clutch is contained in a clutch basket attached to the differential carrier with the crown wheel securing bolts.
Alternate plates of the clutch pack are keyed to the clutch basket and the LH sun gear. A pressure disc is installed on the outer end of the clutch pack and keyed to the clutch basket. A thrust race on the end of the clutch basket incorporates lugs which
extend through the clutch basket onto the pressure disc.

The actuator assembly is mounted on bearings on the outboard end of the clutch basket, against the thrust race. The actuator
assembly consists of input and output actuators separated by five ball bearings. A locking pin in the cover engages with a slot
in the output actuator to prevent it turning, but allow it to move axially. The input actuator engages with the reduction gearbox
and is free to rotate relative to the cover. Ball bearings locate in curved grooves in the mating faces of the input and
output actuators. The bottom surface of each groove incorporates a ramp. Rotation of the input actuator forces the ball
bearings up the ramps in the grooves and induces an axial movement in the output actuator. The thrust race and pressure disc
transfer the axial movement from the output actuator to the clutch pack.



Item Description 1 Actuator 2 Multi-plate clutch 3 Differential The motor is a 12 V dc motor that adjusts the frictional loading of the multi-plate clutch, via the reduction gearbox and the
actuator assembly, under the control of the DLM. Adjusting the frictional loading of the multi-plate clutch adjusts the locking
torque between the crown wheel drive gear and the sun wheel.

Four bolts attach the motor to the reduction gearbox, which is located in position on the cover with two dowels, and secured
with four bolts. An O-ring seals the joint between the motor and the reduction gearbox.

The motor is driven by a 12 V dc feed direct from the DLM. The motor also incorporates the following connections with the
DLM:

A motor temperature sensor, to prevent excessive use from damaging the motor.
Two Hall effect motor position sensors, to enable closed loop control of the motor.

The temperature sensor provides a differential oil temperature signal to the DLM, to prevent excessive use from damaging the
multi-plate clutch.

Differential Locking Module (DLM)

The DLM controls operation of the electronic differential. The DLM is attached to a bracket located on the LH side of the luggage compartment, immediately forward of the fender tail lamp, behind the trim.

bus allows the DLM to communicate with other systems on the vehicle.

A certain amount of differential slip is required to allow the vehicle to turn corners and to remain stable under control of the
ABS. The ADM monitors the driver's demands through primary vehicle controls and automatically sets the slip torque in the differential. The system is completely automatic and does not require any special driver input.
The differential strategy in the ADM includes:

A pre-loading function, increasing locking torque with increased driving torque.
A slip controller to decrease locking torque for optimum comfort, e.g. parking.
The ADM memorizes the position of the motor when the ignition is switched off.

CAN bus messages used by the ADM include wheel speed, steering angle, automatic transmission speed, temperature information, car configuration, axle ratios and mode inputs.

The ADM also sends messages via the CAN bus to tell other control modules on the network the status of the electronic differential. The clutch torque and default mode status are some of the main signals sent out by the ADM.

If the DLM or ADM are replaced, a Jaguar approved diagnostic system must be connected to the vehicle and the differential
self-calibration procedure must be performed. This procedure must also be performed if the motor or electronic differential is
replaced.

If a fault occurs with the electronic differential, the ADM, the DLM, or one of the required input signals, the ADM records an
error code and displays a warning in the message center.
The following messages can be displayed:

Message Description Chime E-DIFF NOT
AVAILABLE Differential temperature has reached the overheat threshold. System deactivated until temperature
returns within limits. Single E-DIFF FAULT Fault has occurred with electronic differential. System deactivated until fault rectified. Single

Published: 11-May-2011
Rear Drive Halfshafts - Rear Drive Halfshafts - System Operation and
Component Description
Description and Operation

System Operation



Rear Drive Halfshafts Component Description

The solid-steel halfshafts are of unequal length, with each halfshaft comprising inner and outer CV (constant velocity) joints.
The CV joints are the 'ball and socket' type packed with grease and protected by gaiters.

The outer CV joint is an interference fit into the wheel hub and secured by a locking nut. The inner CV joint is a slide fit and is
retained in the differential with a spring clip.
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Removal


1. WARNING: Do not work on or under a vehicle supported only by a jack.
Always support the vehicle on safety stands.
Raise and support the vehicle.

2. Remove the LH rear wheel and tire.

Refer to: Wheel and Tire (204-04 Wheels and Tires, Removal and Installation).

3. With assistance, remove the halfshaft retaining nut, and
retain it for the install procedure.
















4. Release the brake caliper. 308-621-2
Installer/Guide, Halfshaft Oil Seal

8.

9.

10.
11. Release the lower arm.



















CAUTION: Do not use a hammer to detach the
halfshaft from the hub assembly, failure to follow this
instruction may result in damage to the halfshaft.

Using the special tools, release the halfshaft from the drive
flange.

Special Tool(s): 204-269, 205-491-1, 205-491









NOTE: Use an additional wrench to prevent the
component from rotating.
Remove the wheel knuckle.













Release the halfshaft from the differential.

5. CAUTIONS:


Do not install the rear halfshaft fully at this stage.


Only install the rear halfshaft until the halfshaft
splines have past the halfshaft oil seal.







6. Remove and discard the halfshaft oil seal plutector.


7. CAUTION: Make sure that the rear halfshaft circlip is
installed correctly by pulling the halfshaft gently to make
sure it is engaged.














8. CAUTION: The final tightening of the suspension
components must be carried out with the vehicle on its
wheels.

Torque: 90 Nm

9.
















10.
11. CAUTION: Install the halfshaft nut finger tight.


NOTE: Do not fully tighten the locking nut at this
stage.













CAUTION: The final tightening of the suspension
components must be carried out with the vehicle on its
wheels.
Torque: 150 Nm













CAUTION: The final tightening of the suspension
components must be carried out with the vehicle on its
wheels.
Torque: 55 Nm

15.
















16. CAUTION: Do not use air tools to install the nut.
Failure to follow this instruction may result in damage to
the component.
Torque: 300 Nm











Check and top-up the differential case.














17.
Install the LH rear wheel and tire.

Refer to: Wheel and Tire (204-04 Wheels and Tires, Removal and Installation).

Brake System - General Information - Brake System
Diagnosis and Testing

Principle of Operation Published: 11-May-2011

For a detailed description of the brake system, refer to the relevant Description and Operation sections in the workshop
manual. REFER to:

Front Disc Brake (206-03, Description and Operation),
Front Disc Brake (206-03, Description and Operation),
Front Disc Brake (206-03, Description and Operation),
Rear Disc Brake (206-04, Description and Operation),
Rear Disc Brake (206-04, Description and Operation),
Rear Disc Brake (206-04, Description and Operation),
Parking Brake (206-05 Parking Brake and Actuation, Description and Operation), Parking Brake (206-05 Parking Brake and Actuation, Description and Operation), Parking Brake (206-05 Parking Brake and Actuation, Description and Operation), Hydraulic Brake Actuation (206-06 Hydraulic Brake Actuation, Description and Operation), Hydraulic Brake Actuation (206-06 Hydraulic Brake Actuation, Description and Operation), Hydraulic Brake Actuation (206-06 Hydraulic Brake Actuation, Description and Operation), Brake Booster (206-07 Power Brake Actuation, Description and Operation), Brake Booster (206-07 Power Brake Actuation, Description and Operation), Brake Booster (206-07, Description and Operation).

Inspection and Verification

Visually examine the front and rear wheel and tire assemblies for damage such as uneven wear patterns, tread worn out or
sidewall damage. Verify the tires are the same size, type and, where possible, same manufacturer. Replace the damaged
wheel or excessively worn tire.
Wheels and tires must be cleared of any foreign matter and tire pressures adjusted to the correct specification.

If the tires exhibit uneven wear or feathering, the cause must be corrected. Check the steering and suspension components for
damage or wear and, if necessary, check and adjust front wheel alignment. REFER to: (204-00 Suspension System - General
Information)
Specifications (Specifications), Front Toe Adjustment (General Procedures).
Visual Inspection
Mechanical Electrical
Brake master cylinder
Brake caliper piston(s)
Brake discs
Wheel bearings
Brake pads
Power brake booster
Brake pedal linkage
Brake booster vacuum hose
Tires
Debris
Parking brake actuator
Parking brake module
Parking brake switch
Damaged or corroded wiring harness
Brake master cylinder fluid level switch Road Test

Carry out a road test to compare actual vehicle braking performance with the performance standards expected by the driver.
The ability of the test driver to make valid comparisons and detect performance deficiencies will depend on experience.

The driver should have a thorough knowledge of brake system operation and accepted general performance guidelines to make
good comparisons and detect performance concerns.

An experienced brake technician will always establish a route that will be used for all brake diagnosis road tests. The roads
selected will be reasonably smooth and level. Gravel or bumpy roads are not suitable because the surface does not allow the
tires to grip the road equally. Crowned roads should be avoided because of the large amount of weight shifted to the low set
of wheels on this type of road. Once the route is established and consistently used, the road surface variable can be
eliminated from the test results.

Before a road test, obtain a complete description of the customer concerns or suspected condition. From the description, the
technician's experience will allow the technician to match possible causes with symptoms. Certain components will be tagged
as possible suspects while others will be eliminated by the evidence. More importantly, the customer description can reveal
unsafe conditions which should be checked or corrected before the road test. The description will also help form the basic
approach to the road test by narrowing the concern to specific components, vehicle speed or conditions.

Begin the road test with a general brake performance check. Keeping the description of the concern in mind, test the brakes at
different vehicle speeds using both light and heavy pedal pressure. To determine if the concern is in the front or rear braking
system, use the brake pedal and then use the parking brake control. If the condition (pull, vibration, pulsation) occurs only
with the parking brake, the concern is in the rear brake system.

If the concern becomes evident during this check, verify it fits the description given before the road test. If the concern is not
evident, attempt to duplicate the condition using the information from the description.

If a concern exists, use the Symptom Chart in order to isolate it to a specific sub-system and condition description. From this
description, a list of possible sources can be used to further narrow the cause to a specific component or condition.

Symptom Chart

Symptom Possible Cause Action Brakes noisy
Brake pads
Brake discs GO to Pinpoint Test A. Vibration when brakes are
applied
Wheels/tires out of balance
Wheel hub nuts loose
Brake caliper mounting bolts loose
Brake pads
Foreign material/scratches/corrosion
on brake disc contact surfaces
Excessive brake disc thickness
variation
Excessive brake disc runout
Wheel bearing wear or failure
Suspension bushing wear or failure
Steering bushing wear or failure GO to Pinpoint Test B. The brakes pull or drift
Tire pressures/wear
Brake calipers
Brake pads
Brake discs
Wheel alignment adjustment
Wheel bearing
Suspension bushings and ball joints GO to Pinpoint Test C. The pedal feels spongy
Air in brake hydraulic system
Leak in hydraulic system
Brake booster/master cylinder
Brake pads GO to Pinpoint Test D. The pedal goes down fast
Air in brake hydraulic system
Leak in hydraulic system
Brake booster/master cylinder
Brake pads GO to Pinpoint Test E. The pedal goes down
slowly
Air in brake hydraulic system
Brake booster/master cylinder GO to Pinpoint Test F. Excessive brake pedal
effort required
Brake pads
Brake booster GO to Pinpoint Test G. Brake lockup during light
brake pedal force
Brake pads
Brake calipers GO to Pinpoint Test H. Brakes drag
Parking brake control
applied/malfunction
Seized parking brake cables
Seized brake caliper slide pins
Seized brake caliper
Brake booster
Pedal gear GO to Pinpoint Test I. Excessive/Erratic brake
pedal travel
Hydraulic system
Brake pads Brake
discs
Hub and bearing assembly GO to Pinpoint Test J. The red brake warning
indicator is always on
Fluid level
Brake master cylinder fluid level
sensor
Parking brake control Fill the system to specification. Check for leaks.
Install a new brake master cylinder fluid reservoir as
required.
REFER to: Brake Fluid Reservoir (206-06 Hydraulic Brake Actuation, Removal and Installation).