Air Suspension - Inconsistent Ride Height
No: 68/01/00/NASRef: WSM Section 60
Issue: 1
Date: 03/03/00
EAS Inconsistent Ride Height
AFFECTED VEHICLE RANGE:
Range Rover (LP) VA346794 to WA409701
SITUATION:
VARIOUS SYMPTOMS INDICATE EAS RIDE HEIGHT PROBLEMS
The customer may experience "EAS FAULT" message center warnings, audible warnings, and driver control switch lights remaining illuminated. In addition EAS may not respond to mode selection as required.
On vehicles within the specified VIN range, the symptoms noted above may be the result of the EAS control unit interpreting height sensor information as being outside of the "normal range." As the result of normal vehicle build tolerance variation, the height sensors can tangent the ECU settings for an error, despite the fact that the vehicle has in fact remained within the correct operating range.
A Fault Code "Height Sensor Out of Range" will be generated.
RESOLUTION:
EAS CONTROL UNIT REPLACEMENT
Replacement of the ECU with a new variant ECU programmed with corrected operating range information will rectify the situation.
PARTS INFORMATION:
RQT100040 EAS Control Unit
WARRANTY CLAIMS:
60.50.89/33 Time 1.00 hrs.
Confirm incorrect height sensor values, replace ECU and calibrate
FAULT CODE: U
Normal warranty policy and procedures apply
REPAIR PROCEDURE
1. Place vehicle on level ground
2. Ensure tires are inflated to specified pressure.
3. Verify cause of owner complaint as follows:
^ Refer to WSM Section 60.50.38 "Depressurize System."
^ Connect TestBook and follow instructions to lower vehicle to the bump stops.
^ Read TestBook values for height sensors at each corner of the vehicle.
NOTE:
If all height sensor readings are above 42 bits with the system fully deflated, normal vehicle build tolerances will not interfere with the height sensor operations.
4. If all height sensor values are above 42 bits, refer to the WSM Section 60 for fault diagnosis and use TestBook to perform procedures to find the faults.
5. If any height sensor value is at or below 42 bits, refer to WSM Section 60.50.04 and install a new control unit (RQT100040). Refer to Figure 1.
6. Calibrate the newly installed ECU following TestBook procedures.
7. Fully check and verify complete and correct operation of the EAS system as guided by TestBook.
8. If faults are encountered during calibration and system operating check, the original ECU was not at fault. Perform the following steps to complete the repair.
^ Install original ECU.
^ Refer to WSM Section 60 "Fault Diagnosis and TestBook."
^ Perform TestBook check to determine root cause of the problem.