Suspension - Front/Rear Undercar Shudder
No.: LTB00029Issue: 2
Date: 16 April 2008
THIS BULLETIN SUPERCEDES LTB00029, ISSUED 08 FEB 2007. CHANGES ARE SHOWN WITH GRAY HIGHLIGHTS IN THE IMAGES.
Section: 204
RIDE AND HANDLING OPTIMIZATION SYSTEM SHUDDER - REPAIR PROCEDURE
AFFECTED VEHICLE RANGE
CONDITION SUMMARY:
'SHUDDER' FELT OR RAPID 'PULSING' NOISE HEARD FROM UNDER THE VEHICLE
Situation:
A customer may report a concern of an under-car 'shudder' from the front or rear suspension, or an under-car rapid 'pulsing' noise heard from the dynamic response valve block or hydraulic tubing. The shudder may continue as long as the driving conditions that created the shudder remain constant, or the shudder may subside, typically in less than five seconds.
Certain driving situations that are most commonly known to cause the concern are as follows:
^ From single wheel inputs as follows:
^ When speed bumps are traversed at an angle
^ Over small step changes in a road surface, such as driveway entrances, broken road surfaces etc.
^ From specific road design and vehicle driving styles as follows:
^ When the vehicle is cornering at a speed between 6 mph (10 kph) to 19 mph (30 kph)
^ Where the road has a significant camber
^ When the steering wheel angle is greater than +/- 10 degrees
^ When the steering wheel angle is held constant for approximately 2 seconds during the turn where the road surface is not perfectly smooth.
The Dynamic Response system control software performs an inaccurate estimation of the road surface conditions, resulting in overcompensation for what it perceives as very small changes in vehicle direction. This overcompensation causes fluctuations in the control pressure delivered to the stabilizer bar actuators producing the shudder.
Action:
Should a customer report a concern regarding the above, refer to the Repair Procedure detailed in this bulletin to update the Dynamic Response system control module software.
PARTS
No parts required
TOOLS
WARRANTY:
NOTE:
Repair procedures are under constant review, and therefore times are subject to change; those quoted here must be taken as guidance only. Always refer to DDW to obtain the latest repair time.
DDW requires the use of causal part numbers. Labor only claims must show the causal part number with a quantity of zero.
REPAIR PROCEDURE
INSTALL LATEST DYNAMIC RESPONSE SYSTEM CONTROL MODULE SOFTWARE TUNE
1. If IDS DVD 103 with Patch File 1 (or later) software is being used, continue from step 6.
NOTE:
A software patch installation help file located on GTR provides instructions for the patch file installation process and could take up to six minutes to download depending on connection speed.
For information on how to confirm that the patch file has been correctly installed onto IDS, refer to the applicable Patch Process Help File located in GTR. Global Technical Reference (GTR) lookup sequence is as follows:
GTR Home > NAS > Diagnostics/ LS - Range Rover Sport/2006 > Patch Files > "Patch Process Help File IDS" link.
2. Logon to GTR from an internet connected PC and download the IDS Patch Process Help File as follows:
^ Select 'Home' from the menu at the top of the main page.
^ From the menus on the left of the page, select 'Diagnostics' as the 'Information Type' and select the relevant model and model year.
^ From the 'All Information' results, select 'Patch Files'.
^ Click the appropriate 'Patch Process Help File' file link.
NOTE:
This could take up to twenty minutes to download depending on connection speed.
3. Using the help file as a guide, follow the instructions to download and save IDS DVD 103 Patch File 1 (or later).
4. Install the software patch file 'IDS DVD 103 - Patch File 1' (or later) into IDS.
5. Verify that IDS successfully restarts.
CAUTION:
A Midtronics PSC-550 Vehicle Power Supply must be connected to the vehicle battery during diagnosis and module configuration. The battery must be sufficiently charged. Care must be taken to ensure that the diagnostic lead is correctly secured and cannot be accidentally disconnected during software update.
6. Connect the diagnostic equipment to the vehicle and begin an IDS session.
7. Note the current software levels of the Dynamic Response System Control Module as follows:
^ Follow the prompts to read the vehicle configuration.
^ When prompted "Do you wish to read diagnostic trouble codes?", select "NO" and then press 'tick' to continue.
^ When the "Content Model" is displayed, select the 'Vehicle Configuration' tab.
^ Select 'Module Information'.
^ Select 'Network integrity test'.
^ Note the software part numbers displayed on the screen.
NOTE:
During module configuration, the on-screen software part number information that IDS will display can be checked against the software part number noted in step 7 above. If the same software part number is displayed, the vehicle already has the desired tune level and the software download process can be discontinued.
8. Configure the Dynamic Response System Control Module software as follows:
^ Return to the 'Vehicle Configuration' screen and select 'Module Configuration'.
^ Follow the on-screen prompts.
^ Select 'Configure Existing Modules'.
^ From the sub-menu, select 'Dynamic Response System Control Module'.
^ Click the [Check Mark] tick-box to continue and follow the on-screen instructions.
^ Note the on-screen software part number information that IDS will display.
9. Compare the Dynamic Response System Control Module software part number displayed on IDS to the software part number noted in step 7 above.
10. If the same software part number is displayed, terminate the tune download.
11. If a different software part number is displayed, complete the tune download to update the software.
12. Exit the IDS session and disconnect the diagnostic equipment from the vehicle.