C155E-92-RIDE HEIGHT PRESSURE VENT CONTROL - PERFORMANCE OR INCORRECT OPERATION (OVERUSE DTC)
For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article .
NOTE: Perform the ASCM PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before diagnosing any overuse DTC's. Refer to STANDARD PROCEDURE.
WHEN MONITORED
Ignition on. Battery voltage between 9 and 16 volts.
SET CONDITION
When the Air Suspension Control Module (ASCM) detects the Pressure Vent Valve energized time exceeding three minutes within the last ten minutes.
POSSIBLE CAUSES
Possible Causes
AIR SYSTEM LEAK
AIR SUSPENSION CONTROL MODULE (ASCM)
NOTE: If DTC C15A1-00 is present also, perform the ASCM PRE-DIAGNOSTIC TROUBLESHOOTING PROCEDURE before diagnosing any overuse DTC's. Refer to STANDARD PROCEDURE.
DIAGNOSTIC TEST
VERIFY THE DTC IS ACTIVE
Turn the ignition on, engine running.
Wait ten minutes.
With the scan tool, record and erase the DTCs.
With the scan tool, read the DTCs in the ASCM.
Is the DTC active at this time?
Yes
Go To 2
No
Go To 3
AIR SUSPENSION CONTROL MODULE (ASCM)
Turn the ignition off to the lock position.
Install a known good relay.
Turn the ignition on.
With the scan tool, erase the DTCs.
With the scan tool, read the DTCs.
Does the DTC remain active?
Yes
Replace the Air Suspension Control Module (ASCM) in accordance with the Service Information. Refer to MODULE, AIR SUSPENSION CONTROL, REMOVAL .
Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE.
No
Test complete, the condition or conditions that originally set this DTC are not present at this time.
Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE.
INTERMITTENT WIRING AND CONNECTORS
Using the wiring diagram/schematic as a guide, inspect the wiring harness and connectors.
Wiggle test the wiring harness and connectors while monitoring the scan tool data relative to this circuit.
Look for the data to change or for the DTC to reset during the wiggle test.
While monitoring the scan tool data relative to this circuit, move the selector switch to each position several times.
Look for the data to change other than as expected or for the DTC to reset.
Were any problems found?
Yes
Repair as necessary.
Perform the ASCM VERIFICATION TEST. Refer to STANDARD PROCEDURE.
No
Test complete, the condition or conditions that originally set this DTC are not present at this time.
