Inspection and Verification

Inspection and Verification

NOTE: Before diagnosing the air suspension system, carry out the air suspension module self-test. If a DTC is present, follow the diagnosis and testing procedures. If no DTC is present, check the vehicle ride height by following the ride height adjustment procedure.

If the system cannot reach the correct ride height, check all of the air tubes and connections for leaks, blockage or damage, height sensor integrity and/or compressor relay operation before installing a new air compressor.
1. Verify the customer concern.

2. NOTE: If the door ajar indicator is illuminated, repair the door ajar indicator. Refer to Instrument Panel, Gauges and Warning Indicators.

Visually inspect for obvious signs of mechanical and electrical damage.

Visual Inspection Chart

Visual Inspection Chart:

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.

4. NOTE: Make sure to use the latest scan tool software release.

If the cause is not visually evident, connect the scan tool to the data link connector (DLC).

5. NOTE: The vehicle communication module (VCM) LED prove out confirms power and ground from the DLC are provided to the VCM.

If the scan tool does not communicate with the VCM:
^ check the VCM connection to the vehicle.
^ check the scan tool connection to the VCM.
^ refer to Information Bus (Module Communications Network), No Power To The Scan Tool, to diagnose no communication with the scan tool.
6. If the scan tool does not communicate with the vehicle:
^ verify the ignition key is in the ON position.
^ verify the scan tool operation with a known good vehicle.
^ refer to Information Bus (Module Configuration) to diagnose no response from the PCM.
7. Carry out the network test.
^ If the scan tool responds with no communication for one or more modules, refer to Information Bus (Multiplex Communications Network).
^ If the network test passes, retrieve and record continuous memory DTCs.
8. Clear the continuous DTCs and carry out the self-test diagnostics for the air suspension module.
9. If the DTCs retrieved are related to the concern, go to Air Suspension Module DTC Chart. For all other DTCs, refer to Control Systems (Multifunction Electronic Control Module). Diagnostic Trouble Code Tests and Associated Procedures
10. If no DTCs related to the concern are retrieved, GO to Symptom Chart. Symptom Related Diagnostic Procedures