Review the system operation in order to familiarize yourself with the system functions. Refer to Automatic Level Control Description and Operation .
Before diagnosing any Automatic Level Control (ALC) System symptoms, perform the ALC self-test. The ALC self-test will test the system operation and display any current fault codes. Refer to Diagnostic Trouble Code (DTC) Displaying for instructions on activating the self-test and displaying fault codes.
• | Inspect for aftermarket devices which could affect the operation of the ALC system. Refer to Checking Aftermarket Accessories . |
• | Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom. |
Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .
Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom: