A/C - Unexpected Maximum Fan Speed
No: LM-412-001Issue: 1
Date: 21 Jul 2005
SECTION: 412-03
Air Conditioning Fan Speed
AFFECTED VEHICLE RANGE:
Range Rover (LM) VIN: 6A202543 to 6A204663
CONDITION SUMMARY:
UNEXPECTED MAXIMUM HEVAC FAN SPEED
NOTE:
The majority of affected vehicles were reprogrammed by Land Rover at port-of-entry.
However, a few vehicles were shipped to Retailers before the port program was implemented.
Situation:
A customer may report a concern that in bright sunshine, the air conditioning fan speed increases to maximum. A software error in the ECU incorrectly interprets data from the solar light sensor mounted in the dashboard.
Action:
Should a customer express concern regarding the above, duplicate the conditions and then cover the solar light sensor. The fan speed should reduce immediately. Refer to the Repair Procedure detailed in this bulletin for corrective action.
PARTS:
No parts required
TOOLS:
"Range Rover 18" T4 Disc or later
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
PROGRAM HEVAC ECU WITH UPDATED SOFTWARE
CAUTION:
Vehicle battery voltage must be maintained above 12.65 volts to ensure the proper transfer of ECU programs.
1. Initiate a diagnostic session using RDS disc "Range Rover 18" or later.
2. From the main screen, select "T4".
3. Select "Diagnostic System".
4. Select "New Range Rover", "Model Year 2006" and "Continue".
5. Enter the complete VIN, then "Continue".
6. Verify the VIN is correct, then "Continue".
7. At the Welcome Screen, select "Continue".
CAUTION:
T4 displays a warning that states:
"WDS is required for Module Programming and Coding".
For this module coding procedure the warning should be ignored.
8. At the Information Screen, select "Continue".
9. Connect the T4 diagnostic tester to the vehicle as instructed.
10. Switch the ignition to position 2 and then select "Continue".
11. Select "Yes" to confirm the VIN.
12. At the TQI Introduction Screen, select "Continue".
13. Select the relevant market and then select "Continue".
14. Select the appropriate vehicle features and then select "Continue".
CAUTION:
Selected input must be 100% correct for the vehicle build specification. Select "Continue" ONLY if the displayed list is correct for the vehicle specification.
15. Verify the vehicle configuration and then select "Continue"
16. Select "System Diagnostics".
17. Select "Air Conditioning", then "Continue".
18. At the Welcome Screen, select "Continue".
19. At the ECU Type Screen, select "Continue".
20. Select "Vehicle Maintenance".
21. Select "ECU Code", then "Continue".
22. Ensure Ignition Switch is in position 2, and select "Continue".
23. When prompted, turn the ignition off for 30 seconds, then turn the ignition to position 2.
24. Wait for 20 seconds and then select "Continue".
25. Select "Abort".
26. Select "Confirm Abort".
27. Select "Exit".
28. Disconnect T4 from the vehicle.
Disclaimer