Initial Inspection and Diagnostic Overview

1. Verify the customer concern.
2. Visually inspect for the obvious signs of mechanical and electrical damage.

Mechanical
- Restricted suspension movement
- Excessive vehicle load
- Crimped, kinked, or leaking airline

Electrical
- Air suspension switch is OFF
- Battery junction box (BJB) Fuse:
- 8 (20A)
- 9 (40A)
- Central Junction Box (CJB) Fuse:
- 9(7.5A)
- 10(7.5A)
- Loose connectors
- Corroded connectors
- Damaged solenoid valve

3. If the inspection reveals an obvious concern that is readily repaired, correct the concern before continuing with Inspection and Verification.
4. If the concern remains after the inspection, use New Generation STAR (NGS) Tester connected to the Data Link Connector (DLC) (located below the steering column) to retrieve continuous diagnostic trouble codes (DTCs) and to execute the air suspension control module diagnostics. Reading and Clearing Diagnostic Trouble Codes
- If the air suspension control module diagnostics passed and no DTCs are retrieved, go to Symptom Chart to continue diagnostics. Symptom Related Diagnostic Procedures
- If DTCs are retrieved, go to Air Suspension Control Module Diagnostic Trouble Code (DTC) Index. Diagnostic Trouble Code Descriptions
- If the air suspension control module cannot be accessed by NGS Tester, go to Pinpoint Test A. Pinpoint Tests