Range Rover (LM) V8-4398cc 4.4L (M62) (2003)
Diagnostic Trouble Code 109 (Height Change In Wrong Direction When Lifting)
The ECU is attempting to increase the height of the vehicle and has detected that the height is decreasing rather than increasing.
Diagnostic Trouble Code 117 (Reservoir Pressure Drops Initially When Filling)
Diagnostic Trouble Code 118 (Reservoir Pressure Drops When Filling)
The ECU is attempting to fill the reservoir and the measured reservoir pressure is decreasing.
Under normal circumstances, the reservoir pressure is expected to drop in the first few seconds after the reservoir valve is opened as the
pressures in the reservoir and common gallery equalize. During this time, the threshold to detect a defect is set larger so that normal operation
won't be detected as a defect. However, a very big pressure drop will set the DTC 117. After a few seconds the reservoir pressure is expected
to rise so the threshold to detect the defect is decreased to increase the sensitivity of this diagnostic. Hence a very big air leak will set DTC 117
while a smaller leak will set DTC 118.
Check the air reservoir for visible damage.
If the reservoir is damaged refer to GTR section 60.50.03 and replace the reservoir.
If an aluminum reservoir is installed, perform the following:
Check the area of reservoir pipe between the valve and the reservoir body for white corrosion.
If any white corrosion is visible in the area of the connector where it is screwed into the reservoir, check for leakages in this area.
If it is not possible to stop the leakage refer to GTR section 60.50.03 and replace reservoir assembly.
Check the reservoir pipe between the reservoir and the solenoid valve for damage.
If the pipe is damaged, replace with a new pipe.
Check the solenoid valve for leakage and repair as necessary.
Check the air pressure relief valve for air leakage. (Figure 1)
If a leak is detected, replace the inline pressure relief valve.
Verify that there is pressure in the reservoir.
Determine if the air compressor exhaust valve is stuck open using T4/RDS diagnostics as follows:
Open the reservoir valve only using the Force Outputs option with all other valves closed.
Monitor that the reservoir pressure does NOT decrease significantly (<0.1bar/20s).
If the reservoir pressure drops significantly, refer to GTR Section 60.50.10 and replace the air compressor.