I too am having suspension issues with my 07 L322 S/C. I've had issues at various times and have always been able to fix them, many times through this forum or others. My latest is a Suspension Fault warning that has progressed into many additional faults, including turning off the Terrain features (all 4X4 systems). But the air suspension holds and vehlcle doesn't drop unless using the manual feature of the GapII tool.
See faults below:
Before Fault Clearing:
VIN SALMF13427A23XXXX
Model L322 - Range Rover 2007
Vehicle scanned on Feb 28, 2020 13:07:23
IIDControl
2.9.9.7 Build 71 Android - IIDTool BT V3.0 B2643
ATCM-Terrain Response
U0401-94 (2C) Invalid data received from engine control module/powertrain control module - Component failure - unexpected operation
( on 28-02-2020 08:30:23 at 222276 mi )
U0402-94 (2C) Invalid data received from transmission control module - Component failure - unexpected operation
( on 28-02-2020 08:30:23 at 222276 mi )
U0416-94 (2C) Invalid data received from vehicle dynamics control module - Component failure - unexpected operation
( on 28-02-2020 08:30:23 at 222276 mi )
U0403-94 (2C) Invalid data received from transfer case control module - Component failure - unexpected operation
( on 28-02-2020 08:30:23 at 222276 mi )
U0421-94 (2C) Invalid data received from ride level control module - Component failure - unexpected operation
( on 28-02-2020 08:30:21 at 222276 mi )
IPC-Instrument Pack
U0248-87 (2F) Lost communication with remote driver utility module - Bus signal/message failure - missing a message
( on 27-02-2020 17:24:45 at 222276 mi )
RLM-Suspension
C1A13-64 (28) Pressure does not decrease when venting gallery - Algorithm based failure - signal plausibility failure
( on 28-02-2020 10:44:20 at 222298 mi )
C1131-92 (6C) Air supply - Component failure - performance or incorrect operation
( on 28-02-2020 08:30:21 at 222276 mi )
VIM-Immobilizer
B1B01-87 (2E) Key transponder - Bus signal/message failure - missing a message
( on 28-02-2020 08:29:30 at 222276 mi )
U0155-87 (28) Lost communication with instrument cluster control module - Bus signal/message failure - missing a message
( on 28-02-2020 09:03:15 at 222298 mi )
After clearing all faults, restarting engine and enabling suspension (via Gap II), a message appears to raise or lower suspension to activate. Then the vehicle became stuck in "Extended Mode" and will not go up or down. Currently sitting at a slightly elevated position. By resetting the ECM's by shorting battery leads the system will again go into the "Suspension Fault" and turn off the Terrain Response and Suspension systems.
These are the current faults after Clearing and Operating Suspension Down:
VIN SALMF13427A23XXXX
Model L322 - Range Rover 2007
Vehicle scanned on Feb 28, 2020 13:09:43
IIDControl
2.9.9.7 Build 71 Android - IIDTool BT V3.0 B2643
ATCM-Terrain Response
U0401-94 (2E) Invalid data received from engine control module/powertrain control module - Component failure - unexpected operation
( on 28-02-2020 13:09:01 at 222327 mi )
U0402-94 (2E) Invalid data received from transmission control module - Component failure - unexpected operation
( on 28-02-2020 13:09:01 at 222327 mi )
U0416-94 (2E) Invalid data received from vehicle dynamics control module - Component failure - unexpected operation
( on 28-02-2020 13:09:01 at 222327 mi )
U0403-94 (2E) Invalid data received from transfer case control module - Component failure - unexpected operation
( on 28-02-2020 13:09:01 at 222327 mi )
U0421-94 (2F) Invalid data received from ride level control module - Component failure - unexpected operation
( on 28-02-2020 13:08:59 at 222327 mi )
IPC-Instrument Pack
U0248-87 (2F) Lost communication with remote driver utility module - Bus signal/message failure - missing a message
( on 28-02-2020 13:08:01 at 222327 mi )
RLM-Suspension
C1A13-64 (AF) Pressure does not decrease when venting gallery - Algorithm based failure - signal plausibility failure
( on 28-02-2020 13:08:59 at 222327 mi )
Looking for some assistance in trouble shooting with the Gap II tool. I'm sure it's a suspension valve issue but which valve. I replaced the seals on the exhaust valve hoping this would solve this issue. Some time ago I also drilled a hole in the exhaust silencer and replaced the dissicant, which cleared suspension faults at that time.