Use customer supplied occurrence information (speed/road surface/symptom) to
understand what is the most probable root cause of the noises observed.



SYMPTOM: single 'knock' OR a series of isolated 'knocks':
Drive Cycle / Conditions: single-wheel and dual-wheel inputs from speed bumps
/damaged road surfaces or similar while traveling ONLY forward at speeds of up
to 25mph (40kmh).
Action: perform the SERVICE INSTRUCTION listed below.

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

SYMPTOM: 'click' noise:
Drive Cycle / Conditions: 'click' noise occurs during harsh cornering, rapid
acceleration, and/or abrupt braking.
Action: refer to Technical Bulletin LTB00618NAS, 'Click' / 'Rattle' Noise
From Engine Compartment When Driving.
If the issue is not rectified after performing the Service Instruction in
this bulletin, remedial work may be required to the steering rack.
Before contacting the Technical HelpLine, raise a Technical Assistance
(TA)request, detailing the following: customer symptoms, road
surfaces, and road speeds that create the noise. After submitting the
TA request, the Technical Helpline will advise the remedial actions
required.

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

SYMPTOM: 'rattle' noise:
Drive Cycle / Conditions: noise occurs while traveling at speeds up to 20mph
(32kmh) over road surfaces shown.
Action: refer to Technical Bulletin LTB00618NAS, 'Click' / 'Rattle' Noise
From Engine Compartment When Driving.
4

SYMPTOM: 'thud' noise:
Drive Cycle / Conditions: noise occurs while braking abruptly at low vehicle
speeds.
Action - 2013-15MY:refer to Technical Bulletin LTB00573NAS, 'Thud' /
'Thump' Noise From Front Suspension On Brake Application .
Action - 2016-17MY: go to the Workshop Procedure below.

WORKSHOP PROCEDURE:

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NOTES:
This Technical Bulletin is written in a specific order where the most likely causes of this issue
are dealt with first. The most likely causes will also give the biggest benefit if addressed. It is
therefore imperative that the steps are followed in order.
Refer to TOPIx for all torques not explicitly specified in this document.
Replacement of any suspension component which affects suspension geometry must be
followed by a four-wheel alignment inspection using the procedure highlighted in the vehicle
Workshop Manual.
VEHICLE TESTING: it is important to identify a test route that highlights the customer
concern of suspension knock and re-test the vehicle over the same test route when identified
in the following procedure. The test route should include roads that have a uneven road
surface or drain covers that allow single wheel inputs. The vehicle speed that highlights the
issue should be noted during the initial appraisal of the customer concern and then replicated
on subsequent test drives.
Typically, noise from the Dynamic Response system can be observed at low vehicle speeds
(10–25mph / 16–40 km/h). Some occurrences of hydraulic knock should be expected. Only
excessive / abnormal knocking noise indicates a concern.

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

Check the Dynamic Response system fluid reservoir for leaks:
If a leak is not present, go to the next Step.
If a leak is present, replace the Dynamic Response system fluid reservoir (see
TOPIx Workshop Manual section 204-06: Ride and handling optimization Removal and installation - Fluid reservoir).
2

Front Suspension Knock Test: vehicles with the Dynamic Response system are expected to
exhibit a low level of hydraulic knock from the system during normal operation as the input
forces are reacted by the Dynamic Response system. Where there is a customer complaint of
excessive / abnormal knocking noise, the following steps should be taken.
Check and rectify basic faults before beginning diagnostic routines.
Verify the customer concern.
Visually inspect for obvious signs of mechanical damage.
Make sure all tire pressures are set according to the tire label in the driver's door
opening.

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Make sure the same test route is used for road test after any remedial work.
3

NOTE:
Do NOT remove the fuse for the Dynamic Response System
Front Suspension Knock Diagnostic Test (refer to Step 1 of the Basic Diagnostic Process
above)

4

NOTE:
A small amount of pivot is normal.
Check the front stabilizer bar links for abnormal play.
If abnormal play is not found, go to the next Step.
If abnormal play is found, renew the stabilizer bar link(s).

5

Carry out road test.
If the issue is not present, return the vehicle to the customer.
If the issue is still present, go to the next Step.

6

Check the front stabilizer bar arm for play.
If the front stabilizer bar arm does not have greater than ± 10mm of play, go to
the next Step.
If the front stabilizer bar arm does have greater than ± 10mm of play, perform a
system bleed (see TOPIx Workshop Manual section 204-06: Ride and handling
optimization - General procedures - Active Stabilization System Bleeding).
Initially only bleed the front stabilizer bar actuator.

7

NOTE:
View of the end of hydraulic valve block from front of vehicle.

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

Check the valve block to body stud clearance.
If there is sufficient clearance between the valve block body and the plastic body
fastener that secures the fuel lines, go to Step 9.
If there is not sufficient clearance between the valve block body and the plastic
body fastener that secures the fuel lines, go to Step 8.
8



Remove the plastic body fastener and drill an axial hole 5mm diameter through the head; this
will allow the body stud to pass through the head of the fixing.
9

Carry out road test.
If the issue is not still present, return the vehicle to the customer
If the issue is still present, go to the next Step.

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10

NOTE:
If the latest specification of front actuator bar is installed, only replace it if it is
damaged/leaking fluid.



2013MY Range Rover (L405) vehicles up to VIN 125193 only: if the knocking noise is still
present and considered unacceptable after performing the above steps, replace the Dynamic
Response front actuator with part number LR052058 (B) (see TOPIx Workshop Manual section
204-06: Ride and Handling Optimisation - Front Stabilizer Bar).
After performing all listed remedial actions, it is possible that a low level of residual knocking
noise may still be present. This low level of knocking noise may be caused by the Dynamic
Response system's hydraulic operation. If the concern has not improved to an acceptable level, go
to the next Step.
11

NOTE:

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On strong customer complaint, confirm which level of valve block is installed. Valve
block shown removed for clarity.



Check the valve block level (CPLA or FPLA).
If the vehicle does have the latest level (FPLA) valve block (✓), go to the Step 22.
If the vehicle does not have the latest level (FPLA) valve block (✕), install a new
valve block (see TOPIx Workshop Manual section 204-06: Ride and handling
optimization - Removal and installation - Valve block).
When all tasks are finished, go to the next Step.
12

Connect the Jaguar Land Rover-approved Midtronics battery power supply to the vehicle
startup battery.

13

CAUTIONS:
A Jaguar Land Rover-approved Midtronics battery power supply must be connected
to the vehicle startup battery during diagnosis / module programming.

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All ignition ON/OFF requests must be performed. Failure to perform these steps may
cause damage to control modules in the vehicle.

NOTE:
The Jaguar Land Rover-approved diagnostic tool must be loaded with SDD154.00
Software Management Pack v299 (or later).
Connect the Jaguar Land Rover-approved diagnostic tool to the vehicle and begin a new
session.
14

Follow all on-screen instructions, allowing the diagnostic tool to read the VIN, identify the
vehicle, and initiating the data collect sequence.

15

NOTE:
When requested, select 'FPLA' valve.
Follow all on-screen prompts.

16

If the hyperlink is not available:
1 Select Service Functions from the Session Type screen.
2 Select the Selected Symptoms tab.
3 Select Dynamic response module - Valve block replacement
4 Select continue.
5 Select the Recommendations tab.
6 Select Run to perform the 'Dynamic response module - Valve block replacement'
option.

17

Follow all on-screen instructions until the application finishes successfully.
1 When all tasks are complete, go to the next Step.

18

If the hyperlink is not available:
1 Select Diagnosis from the Session Type screen.

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2 Select the Selected Symptoms tab.
3 Select Chassis - Suspension system - Vehicle dynamic suspension
4 Select continue.
5 Select Run to perform the 'Dynamic response hydraulic control - system test' option.
19

Follow all on-screen instructions.
If the test does succeed, go to the next Step.
If the test does not succeed, perform additional diagnosis.

20

Exit the current session.
1 Select the Session tab.
2 Select the Close Session option.

21

22

Disconnect the diagnostic tool and battery power supply from the vehicle.

NOTE:
After performing all remedial actions, it is possible that a low level of residual noise will
still be evident, This is due to the systems hydraulic operation. The system is working
correctly and this noise does not adversely affect vehicle stability or performance. If the
customer is still not accepting of this then please contact your local Customer
Relationship Center (CRC) team to discuss the case.
If noise levels have improved to a suitable level, return vehicle to customer.

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