GM Service Manual Online
For 1990-2009 cars only

Important: The following steps must be completed before using the symptom tables.

  1. Perform the Diagnostic System Check - Vehicle , before using the Symptom Tables in order to verify that there are no DTCs set.
  2. Review the system description and operation in order to familiarize yourself with the system functions. Refer to Air Suspension Description and Operation .

Visual/Physical Inspection

    • Inspect for aftermarket devices which could affect the operation of the Air Suspension System. Refer to Checking Aftermarket Accessories .
    • Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
    • Inspect D height using Trim Height Inspection .
    • Inspect for air leaks using Air Suspension Air Leak Diagnosis .
    • Inspect the height sensors and sensor links for any damage or disconnected components.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Electrical Intermittents .

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom:

    •  Rear Air Springs Do Not Inflate
    •  Rear Air Springs Do Not Deflate
    •  Inflator Inoperative
    •  Trim Height Uneven or Low