Page 501 of 3039

Clunk
Clunk is a metallic noise heard when the automatic transmission is engaged in REVERSE or DRIVE. The noise may also occur
when the throttle is applied or released. Clunk is caused by transmission calibration, backlash in the driveline or loose
suspension components and is felt or heard in the vicinity of the rear drive axle.
Bearing Rumble
Bearing rumble sounds like marbles being tumbled. This condition is usually caused by a worn/damaged wheel bearing. The
lower pitch is because the wheel bearing turns at only about one-third of the driveshaft speed. Wheel bearing noise also may
be high-pitched, similar to gear noise, but will be evident in all four driving modes.
Symptom Chart
Symptom Possible Cause Action Noise is at constant tone over
a narrow vehicle speed range.
Usually heard on light drive
and coast conditions
Rear drive axle
For additional information, GO to Pinpoint
Test A. Noise is the same on drive or
coast
Road
Worn or damaged driveshaft joint
Driveshaft center bearing
Wheel bearing
No action required for road noise
Install new components as required Noise is produced with the
vehicle standing and driving
Engine
Transmission
For additional information, REFER to:
Engine - 3.0L/4.2L (303-00 Engine System - General Information, Diagnosis and Testing),
Engine - 2.7L Diesel (303-00 Engine System - General Information, Diagnosis and Testing),
Diagnostic Strategy (307-01A Automatic Transmission/Transaxle - V6 3.0L Petrol,
Diagnosis and Testing). Loud clunk in the driveline
when shifting from reverse to
forward
Transmission calibration
Transmission Mount
Transmission
Suspension components
Backlash in the driveline
Engine idle speed set too high
Engine mount
Using the Manufacturer approved diagnostic
system, re-configure the Transmission
Control Module (TCM) with the latest
available calibration
Inspect and install new transmission mounts
as required
For additional transmission information,
REFER to: Diagnostic Strategy (307-01A Automatic Transmission/Transaxle - V6 3.0L
Petrol, Diagnosis and Testing).
Inspect and install new suspension
components as required
Inspect and install new driveline components
as required
Check and adjust the idle speed as required
Inspect and install new engine mounts as
required Clicking, popping, or grinding
noises
Inadequate or contaminated
lubrication in the rear drive
halfshaft constant velocity (CV)
joint
Another component contacting the
Inspect, clean and lubricate with new grease
as required
Inspect and repair as required
Inspect and install new components as
required
Page 529 of 3039
1
Electronic
differential 2
Differential
Locking
Module
(DLM) Published:11-May-2011
RearDriveAxle/Differential-RearDriveAxleandDifferential-Component
Location
Descriptionand Operation
Page 532 of 3039
6 Oil temperature sensor 7 High speed CAN from suspension control module 8 CJB (central junction box)
System Operation
ELECTRONIC
DIFFERENTIAL
-
5.0L
SUPERCHARGER
VEHICLES
FROM
2010MY
The
multi-plate
clutch
prevents
excessive
differential
slip and
therefore
maximizes
the
traction
performance
of
the
vehicle.
This
is
fundamentally
different
from
'braked'
traction
control
systems,
which
can
only
counteract
differential
slip when it
occurs.
A
certain
amount
of
differential
slip is
required
to
allow
the
vehicle
to
turn
corners
and
to
remain
stable
under
control
of
the
ABS
(anti-lock
brake
system).
The
system
is
completely
automatic and
does
not
require
any
special
driver
input.
The
multi-plate
clutch
actively
controls
the
torque
flow
through
the
differential
and
optimizes
the
torque
distribution in
the
driveline.
The
clutch
biases
the
torque
from
the
differential
to
the
wheel
with the
higher
grip
and prevents
the
wheel
with the
lower
grip
from
spinning.
www.JagDocs.com
Page 533 of 3039
ELECTRONIC DIFFERENTIAL - 5.0L SUPERCHARGER - VEHICLES FROM 2010MY
Item Description 1 Cover 2 LH rear drive halfshaft oil seal 3 Filler/Level plug 4 Temperature sensor 5 Motor 6 Input flange 7 Front mounting points with insulator assemblies 8 Carrier 9 Rear mounting points 10 Breather 11 RH rear drive halfshaft oil seal 12 Magnetic drain plug The electronic differential has the same functionality as the open differential, but it also incorporates a locking and torque
biasing function to give improved traction performance and vehicle dynamic stability. Operation of the electronic differential is
controlled by the Differential Locking Module (DLM).
Page 534 of 3039
A motor and reduction gearbox, attached to the cover.
A temperature sensor installed in the cover.
The DLM (differential locking module) operates the motor of the electronic differential under the control of the ADM (adaptive
damping module).
Exploded View of Electronic Differential
Item Description 1 Circlip 2 Bearing assembly 3 Input actuator 4 Actuator balls 5 Output actuator www.JagDocs.com
Page 536 of 3039

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.
Page 537 of 3039

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
Page 538 of 3039

Rear Drive Axle/Differential - Rear Drive Axle and Differential
Diagnosis and Testing
Principle of Operation Published: 12-May-2014
For a detailed description of the Rear Drive Axle and Differential, refer to the relevant Description and Operation section in the
workshop manual. REFER to: Rear Drive Axle and Differential (205-02 Rear Drive Axle/Differential, Description and Operation).
Inspection and Verification
CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not
guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.
1. Verify the customer concern.
2. Visually inspect for obvious signs of damage and system integrity.
Mechanical Electrical
Fixings that secure Rear Differential Control Module (Heat path
for Module Heatsink)
Fuses/Relays
Damaged, Loose or Corroded Connector(s)
Damage to Wiring Loom/Incorrect Location,
Stretched or Taught
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to
the next step.
4. If the cause is not visually evident, check the system for any logged Diagnostic Trouble Codes (DTCs) and refer to the
DTC index.
DTC Index
For a list of diagnostic trouble codes that could be logged on this vehicle, please refer to Section 100-00. REFER to: Diagnostic Trouble Code (DTC) Index - DTC: Rear Differential Control Module (RDCM) (100-00 General Information, Description and Operation).